TECHNOLOGICAL CARD No. 2

INSTALLATION OF STEEL AND CONCRETE
Span structures with ride on top
ON A 23.6 m LONG BALLAST
JOB CRANE GEPK-130-17.5

To develop projects for the production of work and organization of labor at construction sites, the Orgtransstroy Institute has developed technological maps on “Installation of steel-reinforced concrete railway spans 23.6 m long with a ride on top on ballast.”

Please send comments and suggestions for improving these maps to the Orgtransstroy Institute at the address: Moscow, 119034, 2nd Zachatievsky lane, building 2, building 7.

CHIEF ENGINEER OF THE INSTITUTE

"ORGTRANSSTROY" (B.A. SKLYADNEV)

TECHNOLOGICAL CARD No. 2

INSTALLATION OF STEEL REINFORCED CONCRETE SPANS WITH RIDING ON TOP ON BALLAST LONG 23.6 m WITH JOB CRANE GEPK-130-17.5

I. Scope of application

The technological map was developed on the basis of methods of scientific organization of labor and is intended for use in the development of projects for the production of work and the organization of labor in the construction of bridges.

The technological map provides for the installation on supports on straight sections of the track of metal spans with a reinforced concrete slab included in working together with main beams. Span structures (basic data see Table 1) are taken according to standard project Giprotransmosta inv. No. 739/11. The metal part of the spans (see technological map No. I, Fig. 2) consists of two beams with a solid wall, interconnected by longitudinal and transverse connections.

The reinforced concrete slab is designed prefabricated. The combination of slabs with the main beams is carried out by connecting the metal embedded parts of the slabs with the upper chords of the main beams with high-strength bolts.

The enlarged assembly of the span must be carried out at the installation site in accordance with the technology provided in the technological map “Installation of a prefabricated reinforced concrete roadway on steel-reinforced concrete railway spans 23.6 m long with a ride on top on ballast” at the installation site located on the approach to the bridge under construction or at the nearest separate point.

The installation of the spans is provided by the GEPC-130-17.5 jib crane (Fig. 7), the technical characteristics of which are given in Table. 2.

calculated, m................................................... ........................................... 28

worker, m........................................................ ............................................... 29

Under-console dimensions, m:

smallest (I working position)................................................... ........ 2.70

largest (IV working position)................................................... ...... 5.03

Maximum lifting capacity of the crane, t.................................................... .130 (140)

Distance from the pulley to the automatic coupling axis, m.................................... 13.9; 20.9

Removal of the pulley away from the main path, m.................................... 5.3

Total weight of the crane train, t................................................... ............... 699

Counterweight mass, t:

retractable........................................................ ................................................... 63

suspension................................................. ............................................... 43

Length of crane train, m................................................... ........................... 118.4

Lateral stability coefficient...................................................... .2.37

longitudinal own................................................... ........................... 2.75

The supporting parts for the spans (characteristics of the supporting parts are presented in Table 3) were adopted according to the standard design of the Giprotransmost inv. No. 583 (type II).

Table 3

Characteristics of supporting parts

The technological map was developed in relation to a three-span bridge with spans of 23.6 m.

When linking the map to local construction conditions, the scope of work is clarified with appropriate adjustments to labor costs and material and technical resources.

II. Instructions for production process technology

Before the start of the main installation work of steel-reinforced concrete spans, the following preparatory work must be completed:

An installation site must be constructed on the approach to the bridge under construction (Fig. 8);

Rice. 7. Diagram of the GEPC-130-17.5 crane in working position:

1 - basic structure of the crane; 2 - console; 3 - support platforms; 4 - retractable counterweight; 5 - suspended counterweight; 6 - rear sub-console platforms; 7 - sling beam; 8 - transverse sling beam; 9 - span structure

Rice. 8. Installation site diagram:

1 - temporary deadlock; 2 - jib crane GEPC-130-175; 3 - locomotive; 4 - spans; 5 - sub-console platforms; 6 - gondola cars with crushed stone; 7 - motor vehicle; 8 - materials of the track superstructure; 9 - bridge abutment

A temporary dead-end was laid at the installation site for the installation of two sub-cantilever platforms after bringing the cantilever crane into working position, as well as for placing gondola cars with crushed stone for ballasting the track on the bridge;

Span structures brought up and unloaded on the overpass along the main track must be assembled, roadway slabs, paving slabs, railings must be installed;

The supports are equipped with standard permanent inspection devices (Fig. 9), which are used as scaffolding when installing spans (or the supports are equipped with suspended scaffolds);

From a separate point, a motor vehicle was delivered to the work site to roll out two sub-cantilever platforms from under the front console of the crane (Fig. 10) and the crane was delivered in the transport position.

Ballasting and laying of the railway track on the installed spans is carried out by a team of track fitters, hired for the duration of installation. The work of this team is not included in the technological map.

Work on the installation of spans is carried out in the following sequence:

Install the supporting parts in the design position;

Bring the crane into working position;

The span is being rigged;

Transport and install the span on the supporting parts in the design position;

They check the installation of the span on the supporting parts, unfasten it, lift the sling beam, and return the crane to the next span.

Rice. 9. Viewing devices on supports:

1 - bridge support; 2 - reinforced concrete beams; 3 - reinforced concrete flooring slabs; 4 - railing posts; 5 - handrails; 6 - railing filling

Rice. 10. Scheme of organizing work on delivering ballast to the bridge:

a - diagram of the location of the motor vehicle and the GEPC-130-17.5 jib crane before the start of work; b - diagram of rolling out sub-console platforms from under the front console of the crane; c - diagram of the supply of gondola cars with crushed stone to a temporary dead end; d - diagram of the supply of gondola cars with crushed stone to the bridge; 1 - railway track; 2 - temporary deadlock; 3 - motor vehicle; 4 - jib crane GEPC-130-17.5; 5 - locomotive; 6 - spans; 7 - sub-console platforms; 8 - gondola cars with crushed stone

The supporting parts are installed in the design position on the undertruss platforms verified by level and ruler.

Before installation, the rubbing surfaces of the supporting parts are thoroughly cleaned and rubbed with graphite. Installation of supporting parts is carried out in accordance with the requirements of the project.

Bringing the crane into working position is carried out by the crane team together with a team of structure installers on a straight horizontal section of the track with well-lined ballast under the sleepers.

When bringing the crane into working position, the following main work is performed: connecting electrical cables from the power station car to the crane; disconnecting the sliding counterweight stops; bringing the jacks into working position; lifting and sliding of consoles to the base structure of the crane; connecting the consoles to the base structure with bolts and butt plates; lifting sling beams with removal of slack in cargo winch cables, lifting the basic structure of the crane; bringing the jacks into the transport position, rolling out the under-cantilever platforms from the crane console into a temporary dead end, while first the platforms are moved by a crane to the dead end point and rolled into the dead end, and then the crane is moved back, and the platforms are taken to the dead end by a motor locomotive (see Fig. 10).

Maintenance of the crane mechanisms, control of the remote control, and maintenance of the power plant of the crane are carried out by the crane team. The crane supervisor supervises the work.

Slinging work is carried out in stages:

Lower the rear sling beam, attach a fixed counterweight to it and raise it;

Turn the crane console towards the span, lower the front sling beam and sling the span using a sling device;

The movable counterweight is moved to the rear position, the superstructure is raised and the crane console is turned in the direction of the axis of the main track;

The movable counterweight is moved and finally installed.

The crane supervisor supervises the slinging of the load and the operation of the crane winches. He also monitors the installation of the span.

The slinging of the span is carried out using a slinging device, the rods of which are passed into the holes of the reinforced concrete slab of the roadway, provided for by the work design.

Since the distances between the culverts through which the rods are passed are greater than the distance between the rods of the main traverse, it is necessary to provide in the design of the slinging device a transverse sling beam (suspended to the main sling beam), the rods of which are located at a distance of 3.3 m.

In all cases, after lifting the span to a height of 5 cm, further lifting is stopped in order to check the correctness and reliability of slinging and the position of the load. The preparation of the span for lifting (without slinging), accurate installation of the span and fastening is supervised by the chief engineer or a foreman appointed by management.

The lifting of the span can be continued only if the test results are positive.

The span is lifted to a height that provides a gap of at least 1.5 cm between the bottom of the suspended load and the level of the rail head when the crane passes along the concave sections of the track profile.

The movement of a jib crane in the working position on a section of track located on a freshly poured embankment is permitted only after it has been compacted by running in a locomotive and loaded cars with an axle load of at least 20 t, and on sections of track within freshly dumped cones - after laying half-sleepers between the sleepers with careful padding them.

The procedure for moving the crane along the installed spans is established by the work plan.

The speed of a crane with a load to the installation site along straight sections and along curves with a radius of 300 m or more is allowed no more than 5 km/h, along curves with a radius of less than 300 m - 3 km/h.

To ensure accurate installation of the crane, the following measures must first be taken:

On both lines of rails at the end of the track, one brake shoe is installed (rear brake shoes);

Paint marks are applied to both threads of the rails at the locations where the second pair of shoes are installed (front brake shoes);

To provide preliminary guidance to the driver about the precise installation location of the crane, a red disk is installed on the right edge of the track (along the direction of travel of the crane). The driver must be familiar with the relative position of the disk and the locomotive at the moment the crane hits the front brake shoes.

The crane is delivered to the installation site of the span by a locomotive at a minimum speed. The crane travels the last part of the journey under its own power without the help of a locomotive.

The accuracy of stopping the crane must be within 10 cm. If the crane is forced to stop at a distance of less than 2 m from the rear brake shoes, it is prohibited to move the crane further after stopping. In this case, the crane must be moved back to a distance of 3 - 5 m.

The driver must ensure immediate braking of the crane (locomotive) at the moment the crane hits the shoes.

When moving the crane down a slope of more than 0.008, the crane must be stopped at a distance of at least 5 m from the rear brake shoes and finally installed.

After the final alignment of the installed span, it is unslinged and the jib crane is returned to the construction site.

The expansion joint between the spans is covered with a steel sheet (Fig. 11). Ballasting and installation of track on the span is carried out by a team of track fitters.

Rice. 11. Overlap expansion joints when connecting spans:

a - section along the roadway slab; b - section along the sidewalk slab; 1 - steel sheet; 2 - pin

During the installation of the span in the first span, gondola cars with crushed stone for ballasting the track on it are fed to a dead end. To supply crushed stone to the bridge, a cantilever crane (after installing the superstructure into the span) is driven to the dead end switch, and gondola cars with crushed stone are delivered to the bridge by a motor locomotive. During the installation of the span in the second span, empty gondola cars are returned to the station, and gondola cars with crushed stone are delivered to the dead end to ballast the track in the second and third spans, similar maneuvers are performed.

After installing all the spans, the jib crane is moved from the working position to the transport position.

When installing steel-reinforced concrete spans using a GEPC-130-17.5 jib crane, you should be guided by the following documents:

1. SNiP III-43-75. Bridges and pipes. Rules for production and acceptance of work."

2. SNiP III-A.11-70. "Safety in construction"

3. “Safety rules and industrial sanitation during the construction of bridges and pipes”, M., Orgtransstroy, 1969.

4. “Safety instructions for working on jib cranes” and the corresponding sections of “Crane Operating Instructions”, L., Lengiprotransmost, 1971.

5. “Device rules and safe operation lifting cranes", M., "Transport", 1974.

6. “Instructions for ensuring the safety of train traffic during track work”, M., “Transport”, 1966.

7. “Instructions for signaling on railways of the USSR”, M., “Transport”, 1971.

Safety instructions

Before sending the crane to the work site, it is necessary to check the technical condition of the crane and its rolling stock, including auto brakes and coupling devices.

Moving a crane with technical faults that threaten traffic safety is not permitted.

It is prohibited to suspend the span from the crane until the crane is inspected after it has been brought into working position.

When a crane with a load enters an installed span, the presence of people on the span and near the crane is not allowed; the crane must move in small increments of 3 - 5 m at the command of the crane supervisor.

At a distance of at least 1 m from the end of the rail track, special metal stops are installed, which are included in the crane kit.

While the jib crane is operating on the bridge, careful monitoring of the condition of the spans must be carried out; skewing, swaying, etc. must not be allowed.

When installing a structure with a jib crane, it is prohibited to use braces attached to the structure being installed and going to winches outside the crane.

When lowering the span, the presence of people on or under it is prohibited; workers are allowed to access the support platforms for precise installation of the span only if it is positioned in plan close to the design, without distortions and with a gap between the beam being installed and support platforms no more than 10 cm.

It is prohibited to operate the crane in winds exceeding 6 points (12 m/sec), as well as during heavy rain, thunderstorms, blizzards, ice, dust storms.

In all cases of crane operation, when the load is in a raised position, the operator must not leave the control panel.

III. Instructions for organizing work

It is advisable to carry out work on installing spans with a cantilever crane during daylight hours (in the dark, the work site should be illuminated). The work is carried out by a team of structure installers consisting of 6 people: 6 raz. - 1; 5 sizes - 1; 4 size - 2; 3 size - 2.

The composition was selected based on the condition that all operations for the installation of spans should be performed by one team.

After the superstructure is installed, track installers lay the track on it.

The jib crane is controlled and serviced by a crane crew of 5 people: crane driver (operator) 6 grades. - 1, power plant operator 6 grades. - 1; electrician 5 grade - 1; locksmith 5 grades - 1; rigger 6 sizes - 1. This team is led by the crane supervisor.

General management of work with a jib crane is entrusted to the head (chief engineer) of the bridge construction organization.

The movement of the crane during the work process, as well as the slinging of the span and the operation of the crane winches, is supervised by the crane supervisor. He also monitors the rise and fall of the span.

The installation of supporting parts in the design position is carried out under the guidance of a foreman by a full team of structure installers (2 people for each supporting part). In this case, the installer is 6-bit. works with installer 3 grades, installer 5 grades. with installer 3 types, 2 installers 4 types work together.

The supporting parts are cleaned metal brushes, and straightening with crowbars. The alignment of the supporting parts along the axes and marks is controlled by the surveyor. The installation team works sequentially on all supports during 1 shift. On the next shift, installer 6 grade. with installer 3 sizes carry out a control check of the correct installation of the supporting parts, seal the seam between the slab of the supporting part and the under-truss platform with cement mortar, protecting the cement bedding from blowing out, and install aprons on the supporting parts.

The remaining members of the brigade consisting of 4 people. (5 grades - 1; 4 grades - 2; 3 grades - 1) together with the crane crew, bring the jib crane from the transport position to the working position.

All work to bring the jib crane from the transport position to the working position and then from the working position to the transport position is carried out under the guidance of the crane supervisor.

The connection of cables from the power station car to the crane and platforms is carried out by a 5-grade electrician. from the crane crew and two installers of grade 5 and grade 3 structures.

The detachment of the sliding counterweight stops with the loosening of the fasteners is carried out by a 5th grade mechanic. from a crane crew and 2 installers of grade 4 and grade 3 structures.

Work performed in parallel on both consoles of the crane (bringing the jacks into the working position, lifting the consoles with electric jacks and sliding them to the base structure with rack and pinion jacks, connecting the consoles to the base structure of the crane with butt plates and bolts, lifting sling beams with removing slack from cargo winch cables, lifting the base crane structures) are made on one side by a fitter 5 raz. from the crane crew with installers of grades 5 and 3. and on the other hand - by a rigger of 6 grades. from a crane crew with two installers, grade 4.

The crane driver (operator) carries out all operations related to the operation of winches from the control panel.

Minor work performed during the process of bringing the crane into working position is carried out at the direction of the crane supervisor by individual workers.

The installation of spans is carried out by a full team of structural installers, which is divided into two units of 3 people each: one unit includes installers of 6 categories. - 1.; 4 size - 1, 3 sizes - 1, and the other - installers 5 grades. - 1, 4 sizes - 1, 3 sizes - 1.

The links operate in parallel at the ends of the span. Slinging of the span is carried out simultaneously on both sides. When transporting the span to the installation site, the links are located along the crane train on both sides and accompany it to the bridge. After the crane has precisely stopped and the span has been lowered to a height at which the gap between the bottom of the span and the top of the supporting parts is no more than 10 cm, the links are distributed among the supports and the position of the span is accurately installed and aligned. Upon completion of the installation of the span, the erectors of the structures move to another job until the end of the 3rd and 6th shifts.

The work of covering expansion joints is carried out by six structure installers (6 grades - 1, 5 grades - 1, 4 grades - 2, 3 grades - 2), who bring and install the floor sheet over the roadway slab.

After installing the third span, the team installs sheets on two expansion joints.

Bringing the jib crane into the transport position is carried out by the crane team, assisted by structural installers.

The crane is lowered from the working position to the transport position using jacks alternately from each end of the base structure.

At one end of the base structure there are 5 grade mechanics. from the crane crew and one installer each 5; 4 and 3 sizes; at the other end - rigger 6 sizes. from the crane crew and one installer each 6; 4 and 3 sizes

This distribution continues for other dismantling work (fastening sling beams to platforms, detaching consoles from the base structure and securing consoles to platforms), which are carried out in parallel at both ends of the crane.

The crane driver (operator) is at the control panel and carries out all operations related to the operation of the winches.

All work to disconnect and remove power supply cables and secure crane equipment for transportation is performed by the entire crane crew and four structural installers as directed by the crane supervisor.

IV. Schedule of work for installation on supports of three spans 23.6 m long using a cantilever crane GEPC-130-17.5

Legend: ____ - work of the installation team; _ _ _ _ - crane crew work

Notes The numbers above the lines indicate the number of workers, below the lines the duration of work in hours.

V. Calculation of labor costs for the installation of three spans 23.6 m long

	Code code	Name of works	Squad composition	Unit	Scope of work	Per unit		For the full scope of work
						time standard man-hour	price, rub.-kop.	labor costs, man-hour	cost of expenses, rub.-kop.
		Bringing the GEPC-130 crane into working position	Structure installers:
			Crane crew
	§ 5-4-15 No. 1, 2 a and b	Installation of support parts	Structure installers:	One support part
		movable
		motionless
		Installation of beams (spans) using a GEPC-130 crane on supports	Structure installers:	One beam (one span)
			Crane crew
	Local standards of Mostootryad No. 10 Mostotrest	Covering expansion joints	Structure installers:
		Bringing the GEPC-130 crane into transport position	Structure installers:
			Crane crew
		Total: for structure installers
		for crane crew
		crane operation
		Total (person-day, machine-shift)

VI. Main technical and economic indicators

The name of indicators	Unit	According to calculation A	According to schedule B	By what percentage is the indicator according to the graph greater (+) or less (-) than according to the calculation?
Labor costs of structure installers
The same for 1 linear. m bridge
Average level of workers
Daily average wage one worker
Jib crane time consumption

VII. Material and technical resources

A. Basic materials, semi-finished products, parts and structures

B. Machines, equipment, tools, inventory

Name	Brand, GOST	Quantity
Jib crane	GEPC-130-17.5
Inventory slinging devices
Wrenches
Metal brushes
Tape measures 10 and 20 m long
Steel meters
Theodolite

VIII. Map of operational quality control of work

Installation of a steel-reinforced concrete span structure with a length of 23.6 m per span using a cantilever crane GEPC-130-17.5

Note. The thickness of the cement mortar under the base slab should be between 10 - 25 mm.

Intermediate support diagram

SNiP III-43-75

	Basic operations subject to control	Preparation of installation sites for spans	Installation of spans
	Composition of control	Position of undertruss platforms, installation of supporting parts	Position of the span when installing it on supporting parts
	Method and means of control	Instrumental, level, theodolite, steel tape measure	Visual, instrumental, theodolite, steel tape measure
	Mode and scope of control	Permanent, every supporting part	Each span
	Person supervising the operation	Foreman, surveyor	Chief engineer of SMEs, surveyor
	Person responsible for organizing and exercising control	Chief Engineer SME
	Services involved in monitoring	Geodetic survey	Geodetic survey
	Where are the control results recorded?	Work log, form 1.1	Installation work log, form 6.1. Geodetic inspection report, form 2.4. Acceptance certificate for assembled spans, form 5.38

PDF format

Work order:

The general procedure for installing the span is as follows:

The elements of the span structure are delivered to the work site from temporary storage sites by motor transport.

Integrated assembly is carried out at 12-15 track intervals using railways. crane KDE-251. The crane operates from track No. 15, when the voltage in the contact network is removed and it is diverted towards track 16.

The crane operates on outriggers with outreaches of 4.5-9m. The maximum weight of the load (flat truss) is 6t. Integrated installation is carried out in the following sequence:

Support cages are installed under the lower chords of the trusses and under the transverse beams in the lower chords of the trusses.

Cross beams are installed on the cages.

A flat truss (farthest from the crane) is fed onto the cages and the mounting bolted joints with the transverse beams are assembled without removing the slings. WITH outside the truss is fixed with struts and clamps.

The slings are removed (path number 12 is also closed).

Additionally, the transverse beams are loaded from the ends opposite to the plane of the truss with a load (for example, FBS blocks) as an obstacle to tipping over.

A second flat truss is supplied and assembly bolted connections are made.

Installation of the enlarged part of the span into the design position is carried out by a truck crane "ііебегг" ИТМ-1350.

The crane operates at this site with a boom of 1.=40.2m, on outriggers with a base: 8930x8530, with counterweights, a total weight of 140t, at a boom radius of -22/25m. The lifting capacity of the crane is 41/35t, the weight of the lifted block is -30t.

Installation in the design position is carried out in the “window”, with the closure of train traffic on railway lines 11 and 12. tracks, with voltage relief in the contact network, lasting 7 hours.

Tracks Nos. 15 and 16 are closed with voltage relief in the contact network 3-5 days before the “window” for the installation of the span to allow installation of a temporary support between tracks 15-16 and open 3-5 days after the “window” (after its dismantling ).

The need for the necessary machines and mechanisms

 Truck crane “Liebherr” LTM-1500 (g/c-500t) …………. 1 PC

 Truck crane “Liebherr” LTM-1350 (g/c-350t) …………. 1sh

 Truck crane “Liebherr” LTM-1200 (g/c-200t) …………. 1 PC

 Truck crane “Liebherr” LTM-1090 (g/p-90t)………..…. 1 PC

 Railway crane "Sokol-80.1" as part of household equipment. trains……………...........1pcs

 Mobile platform as part of household items. trains No. 3.…….……… 1 piece

 Railway faucet KDE-251……………………………..…………………………….. 1 piece

 ADM ECHK trolley……………………………………………………………………………….1pcs

 Mobile power station with a capacity of 40 kW………..………..1 piece

When starting to install a new bridge, an engineer is faced with a number of factors that influence the choice of construction method; these include: terrain conditions, installation time, time of year, the nature of the watercourse being crossed, the need for trains to pass over existing bridges and the type of structure.
Therefore, it is rarely possible to choose an assembly method by analogy with the available examples. In each individual case it is necessary to investigate character traits of this construction in order to correctly design the work for this structure.
Only comparatively not a large number of bridges are built on new lines or in new locations. Therefore, when constructing or replacing bridges on existing roads, in some cases the builder’s task is complicated by the need to remove the operating spans while creating the least amount of interference with train traffic. Often the engineer must simultaneously make a decision technical problems carefully study the train traffic conditions, linking the work project with them.
Existing methods for installing spans can be divided into two main classes: with scaffolding and without scaffolding.
Small span structures of simple design, as a rule, are installed without scaffolding, especially in cases where train traffic can be interrupted during work; Scaffolding is sometimes used to assemble small spans from individual blocks.
Longer spans crossing deep and fast rivers, usually mounted in a hinged manner.
Scaffold. The choice of scaffolding system depends on local conditions and can have a significant impact on construction costs.
Depending on their purpose, scaffolding can vary greatly in design. This includes sleeper cages, rows, frame supports, as well as large temporary structures, such as construction and installation overpasses, temporary structures for passing trains, and bypass structures.
Temporary bridges, built to carry railway traffic during construction, are similar in design to conventional overpasses and can be reused (up to 3 times) after dismantling and rebuilding. They are equally suitable for the construction of new bridges and for the reconstruction of existing ones.
When constructing overpasses, scaffolding is often used in addition to a temporary bridge. On these scaffolds, which are frames located next to the existing track, the new span is assembled on skids or rollers, and then installed in place using a side slide. With this method, railway equipment is not used for installation, and work is carried out regardless of the movement of trains.
In cases where the construction of a temporary bridge is undesirable for one reason or another, a similar method is sometimes used. Next to the existing track, assembly scaffolds are built on one side for assembling the new span, and on the opposite side, scaffolds are built for accepting the old span. After the old span is rolled transversely, a new span is rolled into the thus freed span. With this method, the scaffolding is simplified, but inconveniences arise for train traffic, since all installation is carried out using equipment on the railway track from the existing track.
Scaffolds installed on watercourses may be subject to impacts from ice drift and floating objects, as well as sudden changes in water level. This may pose a hazard to the installation and to passing trains. The installation procedure should reduce this danger to a minimum.
All scaffolding must be correctly assembled and equipped with reliable connections: they must be maintained in good condition during service.

Under-truss sites.

Before installing the metal span into place, it is necessary to prepare appropriate undertruss areas. When building new bridges, this is done during the construction of supports, the upper parts of which are precisely designed in plan and height. Anchor bolts are placed exactly in the designated places during the process of laying the support, or sockets are drilled for them in the hardened concrete and the bolts are filled with mortar.
Usually, to ensure proper support of spans, a layer of quick-hardening mortar is added immediately before their installation on the under-truss areas. For this purpose, patented non-shrinking compositions made of cement, sand, metal filler and other impurities are often used.
In some cases, between the masonry and the support slabs of the spans, gaskets made of several layers of rubberized canvas, treated with high pressure at high temperature. The purpose of these gaskets is to uniformly distribute pressure and absorb vibrations that could lead to mechanical wear at the points where the slab comes into contact with the masonry.

Equipment for installation.

For the installation of spans, a variety of equipment and tools are used, the most important of which are cranes, jacks, compressors and devices for riveting, welding and bolting.

Lifting equipment.

When installing spans, mechanical lifting equipment is usually used, although sometimes hand winches are used to lift light loads. Mechanically driven winches are used for lifting heavy elements of spans, reinforced concrete slabs, rails, beams, etc., as well as for moving and driving piles.
Winches can be used independently or as part of crane equipment. For work on the installation of spans and other construction work associated with the need to lift large weights, lifting equipment of the same type is used as winches on cranes, excavators and pile drivers. Thanks to improvements made to the design and manufacturing methods of winches, and especially to their control system, these mechanisms are completely reliable in operation and can be used in all operations, including those carried out from the railway track.

Cranes.

Moving and mounting heavy structural elements carried out using cranes (locomotive, derricks, portal). The most versatile of those used in the installation of railway spans is the locomotive erection crane, which is capable of moving along the track, lifting and turning the load. Emergency cranes and cranes mounted on caterpillar or truck-mounted vehicles are also used. The latter are most suitable for installing overpasses over streets. There are cranes equipped with diesel engines, gasoline engines, and steam engines. They are discussed in more detail in the article "".
A derrick car is a regular railway platform on which a derrick crane is mounted. Previously, such cranes were very common, but starting in 1925, they began to be replaced by locomotive cranes. However, many installation organizations use a certain number of derrick cars in their work. The fact is that due to the location of the crane boom heel not in the center, but at the end of the platform, the derrick car, when the boom is positioned along the axis of the track, can lift a load that is 50-60% more than the load lifted by a locomotive crane of equal lifting capacity.
On the other hand, when the boom is in a lateral position, the load capacity of a locomotive crane is greater than that of a derrick car. Both types of cranes are equipped with outriggers. The advantage of locomotive cranes is their self-propelled nature. Derrick cars are distinguished by their simple design. To lift light elements, in addition to hand winches, they also use drive ones with an air motor.
In Fig. Figure 1 shows the installation of the main beam with a derrick crane.

Rice. 1. Installation of the main beam weighing 77.4 tons, length 30.5 m using a combination derrick crane mounted on a wagon

Rice. 2. The bridge is raised to a height of 1.68 m using 91 tons of jacks driven by pneumatic motors.
To avoid interference with train movement, the lifting was carried out in 5 stages
Rigid-legged derricks and portal cranes are successfully used for the installation of heavy spans of large spans of almost all types. Their distinctive feature is the low relative weight per unit load capacity.
A large number of variations of these cranes can be made, adapting them for special purposes, for example for the installation of pylons of suspension bridges and long drop-down spans assembled in the open state.
Rigid-legged derricks are often designed so that their height can be increased as they are installed.
Compressors. Compressors are an important piece of installation equipment. Selecting the proper type and operating the compressor requires serious attention.
Sometimes, to operate the compressor, taps are used, which are always available at the installation site.
The most economical in terms of cost and time are mobile compressors that are mounted together with an engine (gasoline or diesel) and an air collector and are ready for immediate use.
Typically, a compressor with an air supply of 4.5 m31 min satisfies the installation requirements.
A compressor of this capacity, having an air collector on the frame, is capable of providing compressed air the work of 2-3 teams of riveters. When installing an additional air collector on the line, the same compressor ensures the work of 4-5 teams.

Jacks.

The jack is a portable lifting mechanism, widely used in railway work, including for the installation of spans. The most common jacks are lever, hydraulic and pneumatic. In hydraulic jacks, lifting is carried out by a piston subject to hydraulic pressure. In low-power lever jacks, a gear rack is used for lifting, moved by a pawl on the lever.
In powerful lever jacks, the rod is threaded and rotates in a cage under the action of two bevel gears. The rod ends externally with a ratchet to engage the lifting arm.
The mechanism of pneumatic jacks (Fig. 2) is similar to the mechanism of powerful lever jacks, with the only difference that the movements are carried out not manually, but by an air motor. There are jacks lifting force from 4.5 to 91 tons and more.
Screw jacks with a lifting capacity of 45 tons are very suitable for the construction and repair of bridges, having a relatively low weight and low height, although they have a lifting height of only 11.5 cm. Both high-speed jacks and jacks with a normal lifting speed are highly powerful, stable and simple by design. High speed jacks weigh slightly more than normal speed jacks. These jacks have a height of 56-69 cm and are equipped with ball bearings; lifting height 25-40 cm. They are most suitable for lowering heavy spans.
Lifting heavy spans with jacks is associated with difficulties and danger. It is necessary to arrange a sufficiently reliable foundation under the jacks, to take measures against the possibility of displacement or damage to the lifted load and to ensure safety precautions.

Equipment for riveting.

When constructing steel bridges, the quality of the riveting work is of utmost importance. It is necessary to strive to ensure that the largest proportion of rivets are supplied at the factory. Rivets for assembly riveting are usually supplied by the factory along with all elements of the span.
Small portable hand forges are usually used to heat rivets. As a rule, they are designed for coal, although liquid fuel is also widely used.
The final purpose of riveting, which is to form the head and set the rivet shank until it fills the hole, is achieved by hammer blows when the metal is in a hot state. For this purpose they use pneumatic tools, which allow you to achieve significant cost savings compared to manual riveting by reducing labor costs, increasing the pace of work and improving their quality.
When riveting, support is used various designs. With pneumatic riveting, pneumatic support plays an essential role, creating pressure from the rivet head and holding it in the proper position while the new head is being formed.
A special tool was invented for riveting in inconvenient places, which are inevitable during the construction of any bridge.
When installing steel spans, the following are also required: auxiliary tools, such as reamers, wrenches, hooks for transporting large elements. Small tools and devices are simple and low cost. However, care must be taken that they are comfortable for work.
An important part of equipment for the installation of bridges and other rigging work are also hoists and pulleys. In the construction and repair of bridges, pneumatic tools are successfully used for drilling and reaming holes, cutting threads, grinding, tightening nuts, drilling holes in masonry for anchor bolts, transporting light elements, etc. Electrified tools and devices are also useful. Their use increases with the increase in the number of mobile power plants.

High strength bolts.

Research has shown that rivets placed hot or cold do not fill holes tightly and that force transmission in rivet joints is often due to friction.
These circumstances have led to increased interest in high-strength bolts as a connection method. In construction, the use of bolted connections is more profitable than riveted ones, especially for structures carried out in remote areas where the necessary equipment for riveting is not always available. During installation, it is also more profitable to immediately install high-strength bolts than conventional mounting bolts, which are later replaced with rivets.
Test results conducted by the Association of American Railroads (AAR) Engineering Department show that high-strength bolted joints are 10% stronger than conventional riveted joints and 15% stronger than cold-rivet joints.
If destruction of rivet joints can be observed in the net cross-section (weakened by holes), then in bolted joints the gross cross-section of the element is subject to destruction. This circumstance indicates that the tightening effect of the bolts exceeds the effect of stress concentration at the edges of the holes.

Rice. 2. Driving bolts during installation using mechanical impact wrenches

Field tests show that after six years of service, high-strength bolts are tightly seated in structural joints, while rivets in similar joints have become loose.
The introduction of bolted connections is facilitated by the use of dynamically calibrated pneumatic wrenches that create a given torque and are equipped with an automatic shut-off valve. These keys are discussed in Chapter II of the first section, “Mechanized and Hand Tools.”
In Fig. Figure 2 shows the installation of bolts with a mechanical impact wrench. Experiments have shown that in the absence of such keys, the required tension value will be created if the bolt nut is turned one full turn after tightening it by hand until it touches tightly (with the mounting bolts tightened).

TYPICAL TECHNOLOGICAL CARD (TTK)

CONSTRUCTION OF BRIDGE SPRINGS

I. SCOPE OF APPLICATION

I. SCOPE OF APPLICATION

1.1. A standard technological map (hereinafter referred to as TTK) is a comprehensive organizational and technological document developed on the basis of methods of scientific organization of labor for performing the technological process and defining the composition of production operations using the most modern means mechanization and methods of performing work using a specific technology. TTK is intended for use in the development of Work Performance Projects (WPP), Construction Organization Projects (COP) and other organizational and technological documentation by construction departments. TTC is integral part Work production projects (hereinafter referred to as WPR) and are used as part of the WPR in accordance with MDS 12-81.2007.

1.2. This TTK provides instructions on the organization and technology of work on the construction of bridge spans.

The composition of production operations, requirements for quality control and acceptance of work, planned labor intensity of work, labor, production and material resources, industrial safety and labor protection measures have been determined.

1.3. Regulatory framework for the development of a technological map are:

Standard drawings;

Construction codes and regulations (SNiP, SN, SP);

Factory instructions and technical conditions (TU);

Standards and prices for construction and installation work (GESN-2001 ENiR);

Production standards for material consumption (NPRM);

Local progressive norms and prices, norms of labor costs, norms of consumption of material and technical resources.

Reducing the cost of work;

Reducing construction duration;

Ensuring the safety of work performed;

Organization of rhythmic work;

Rational use of labor resources and machines;

Unification of technological solutions.

1.5. On the basis of the TTK, Working Technological Maps (RTK) are being developed for the implementation of certain types of work (SNiP 3.01.01-85 * “Organization of construction production”) for the construction of bridge spans.

The design features of their implementation are decided in each specific case by the Working Design. The composition and degree of detail of materials developed in the RTK are established by the relevant contracting construction organization, based on the specifics and volume of work performed.

The RTK is reviewed and approved as part of the PPR by the head of the General Contracting Construction Organization.

1.6. The TTK can be tied to a specific facility and construction conditions. This process consists of clarifying the scope of work, means of mechanization, and the need for labor and material and technical resources.

The procedure for linking the TTC to local conditions:

Consideration of map materials and selection of the desired option;

Checking the compliance of the initial data (amount of work, time standards, brands and types of mechanisms, building materials used, composition of workers) with the accepted option;

Adjustment of the scope of work in accordance with the chosen option for the production of work and a specific design solution;

Recalculation of calculations, technical and economic indicators, requirements for machines, mechanisms, tools and material and technical resources in relation to the chosen option;

Design of the graphic part with specific reference to mechanisms, equipment and devices in accordance with their actual dimensions.

1.7. A standard flow chart has been developed for engineering and technical workers (work foreman, foremen, foremen) and workers performing work in temperature zone III, in order to familiarize (train) them with the rules for carrying out work on the construction of bridge spans using the most modern means of mechanization, progressive designs and methods of performing work.

The technological map is designed for the following volumes:

II. GENERAL PROVISIONS

2.1. The technological map has been developed for a set of works for the construction of bridge spans.

2.2. Work on the construction of bridge spans is carried out by a mechanized team in one shift, the duration of working hours during a shift is:

2.3. The work sequentially performed during the construction of bridge spans includes the following technological operations:

Geodetic layout and fixation of the axes of support of the beams of the span on the supports;

Arrangement of assembly sleeper cages;

Enlarged assembly of beam blocks of the span structure;

Enlarged assembly of the middle block of the orthotropic plate;

Installation of the span.

2.4. When constructing bridge spans, the main materials used are: high-strength bolts M22x80 strength class 10.9 steel grade 40X, corresponding to GOST 52644-2006; high-strength nuts M22.10 strength class 10, steel grade 40X, corresponding to GOST 52645-2006; M24 washers steel grade St5sp2, corresponding to GOST 52643-2006; enamel PF-1331 according to GOST 926-82 *; primer GF-021 according to GOST 25129-82; electrodes 4.0 mm E-42 according to GOST 9466-75.

2.5. The technological map provides for the work to be carried out by a complex mechanized unit consisting of: mobile crane Liebherr LTM 1400-7.1 (max load capacity Q=400 tons at reach L=3.0 m, telescopic boom =60 m); mobile crane Liebherr LTM 1500-8.1 (max load capacity Q=500 tons at reach L=3.0 m, telescopic boom =84 m); truck tractor KamAZ-54115-15 with onboard semi-trailer SZAP-93271 (carrying capacity Q=25.0 t); automobile jib crane KS-45717 (load capacity Q=25 t); bulldozer B170M1.03VR (=4.28 m, h=1.31 m); dump truck KamAZ-6520 (load capacity Q=20.0 t).

Fig.1. Mobile crane Liebherr LTM 1500-8.1

Fig.2. Mobile crane Liebherr LTM 1400-7.1

Fig.3. Load characteristics of the KS-45717 truck-mounted jib crane

Rice. 4. Truck tractor KamAZ-54115-15 + semi-trailer SZAP-93271

Fig.5. Bulldozer B170M1.03VR

Fig.6. Dump truck KamAZ-6520

2.6. Work on the construction of bridge spans should be carried out in accordance with the requirements of the following regulatory documents:

III. ORGANIZATION AND TECHNOLOGY OF WORK EXECUTION

State construction site transferred by the Customer must comply with the terms of the contract and the requirements of section 4 Technical regulations on the safety of buildings and structures and other documents established by federal laws and laws of the constituent entities of the Russian Federation.

The construction site is considered prepared for installation work, if the site has been cleared and leveled, entrances and exits have been arranged, the site has been provided with electricity, and lighting has been installed.

3.4.3. Elements of the superstructure are delivered from the manufacturing plant to the on-site warehouse truck tractor KamAZ-54115-15 with semi-trailer SZAP-93271 .

3.4.4. Unloading and storing elements of the span structure at the on-site warehouse is carried out automobile jib crane KS-45717 in the area of ​​operation of the installation crane with the help of workers who are part of the installation team.

It is prohibited to throw elements from vehicles or drag them on any surface. During loading, slings made of soft material should be used.

During loading and unloading operations, transportation and storage of elements of span structures, they must be protected from mechanical damage and exposure to precipitation.

Spacers must be placed between the horizontal rows of elements, one above the other strictly vertically. The width of the spacer is determined taking into account the crushing strength of the wood. The thickness of the gasket must ensure a gap from the top of the mounting loop of at least 20 mm and be at least 25 mm. The height of the stack should not exceed the width of the stack more than twice and should not exceed 2.5 m.

Storage areas are separated by through passages with a width of at least 1.0 m every two stacks in longitudinal direction and after 25 m transversely. To pass to the ends of the elements, gaps equal to 0.7 m are arranged between the stacks.

The required supply of structures is determined depending on production needs, transportation distance and conditions of receipt of structures. In industrial construction, the time margin between delivery and installation of structures is up to two weeks. When determining the stock of structures, the need for a reserve in case of unforeseen delays in deliveries and the time required to complete the structures are also taken into account.

3.4.5. After the concrete underframes reach 70% of the design strength, the support axes of the metal beams of the spans are divided into supports. The initial data for alignment work are the coordinates and heights of the points of the geodetic alignment base accepted from the Customer.

To break down the support axes, an inventory tubular cast-off is used. The position of the alignment axes of the piles is fixed with steel wire strings, stretched along the axes on the cast-off, and transferred to the surface of the site using plumb lines lowered from the stretched strings.

Fig.7. Inventory cast-off

The alignment of the support axes should be carried out using a comparator tape in the longitudinal and transverse directions, guided by the working drawings of the span.

The procedure for carrying out marking work using the linear notching method. This method is used when determining points on the ground, slightly distant from the points and sides of the geodetic base. The method of linear serifs is that based on known distances " A ", "V "from fixed points (points of the geodetic basis)" A ", "IN "to a certain point of the structure" WITH "radii equal to segments" A ", "V " arcs are drawn on the ground, at the intersection of which the desired point is located. The length of the linear notches should not exceed the length of the measuring device, otherwise the notches will not be made accurately enough. When determining the points of critical structures using this method, including supports with a single-row arrangement of piles, the position the desired point " WITH "define not by two, but by three serifs, for example: from the reference point" A "and from two aim points" B " And " IN "radii equal to the calculated distances" A ", "b "And " V ", draw arcs at the intersection of which the desired point is located " WITH ".

The completed alignment work must be presented to the Customer's technical supervision representative for inspection and documentation by signing a Certificate of alignment of support axes on the ground in accordance with Appendix 2, RD 11-02-2006.

To the act of laying out the support axes, it is necessary to attach a schematic plan of the bridge crossing indicating the location of points, types and depth of placement of signs securing the GRO, coordinates of points, their chainage values ​​and elevations in the accepted system of coordinates and heights.

3.4.6. Device sites for building a slipway start with planning and profiling the surface of the site according to given vertical marks bulldozer B170M1.03VR . The dimensions of the site must provide the possibility of placing installation cranes and have convenient entry.

The completed work on planning and profiling the surface of the site for building a slipway must be presented to the Customer's technical supervision representative for inspection and documentation by signing an Inspection Certificate hidden work in accordance with Appendix 3, RD 11-02-2006.

3.4.7. For device installation site KamAZ-6520 dump trucks crushed stone of the 40-70 mm M800 fraction is delivered to the planned site and leveled bulldozer B170M1.03VR layer 25-30 cm and compacted vibrating plate TSS-VP90N in 8 passes along the trail.

The completed work on the construction of the crushed stone base of the site must be presented to the Customer's technical supervision representative for inspection and documentation by signing an Inspection Certificate for hidden work in accordance with Appendix 3, RD 11-02-2006.

To planned and compacted crushed stone base truck crane KS-45717 stacked road slabs PDN-14AtV.

Fig.8. PDN-14AtV slab, L=6000 mm, B=2000 mm, H=140 mm, P=4.2 t, V=1.68 m

Fig.9. Reinforced concrete laying scheme slabs on a construction site

The completed work on the installation of the installation site must be presented to the Customer's technical supervision representative for inspection and documentation by signing an Inspection Certificate for critical structures in accordance with Appendix 4, RD 11-02-2006.

This act must be accompanied by an executive geodetic diagram indicating its dimensions in plan, profile and absolute surface elevations.

Upon completion of the installation of the span, the crushed stone base and slab covering are dismantled and removed from the construction site.

3.4.8. Slipway for assembling the superstructure constructed from foundation blocks FBS 1200x600x600 mm (26 pcs.) and FBS 1200x600x300 mm (4 pcs.), mounted on reinforced concrete slabs 2P30.18 measuring 3000x1750x170 mm (24 pcs.). Placed on top of FBS wooden beam section 150x150 mm (6.0 m).

The completed work on the construction of the slipway must be presented to the Customer's technical supervision representative for inspection and documentation by signing the Inspection Certificate for critical structures in accordance with Appendix 4, RD 11-02-2006.

This act must be accompanied by an executive geodetic diagram indicating the dimensions of the slipway in plan, profile and absolute elevations of the top of the surface.

Fig. 10. Plan of the slipway for assembling the superstructure

3.4.8.* Temporary support BO2 assembled from a rolled metal profile. The total weight of the metal of the temporary support is 8149.3 kg (see Fig. 11).

________________

*Numbering corresponds to the original. - Database manufacturer's note.

Installation of temporary support metal structures is carried out in accordance with the requirements of SNiP, Working Design, approved Work Project and manufacturer's instructions. Replacement of metal structures and fastening materials provided for by the project is allowed only by agreement with the design organization and the customer.

Specification of metal structures

Table 1

	Name		Unit weight, kg

Fig. 11. Temporary support BO 2

Welded installation connections should be made in accordance with GOST 5264-80 * using E42A electrodes in accordance with GOST 9467-75 *. The height of welds not indicated on the drawings should be taken according to the smallest thickness of the elements being welded. The minimum thickness of fillet welds should be taken according to table 38 SP 16.13330.2011.

All welds must be presented to the Customer's technical supervision representative for inspection and signing of the Inspection Certificate for hidden work in accordance with Appendix 3, RD 11-02-2006.

The progress and results of welding work must be entered in the Welding Work Log (form F-56,).

Paint metal structures with two layers of PF-1331 enamel over a layer of GF-021 primer with a total thickness of at least 80 microns after all welding work has been completed. The appearance of the paint and varnish coating must correspond to the indicators of class V according to GOST 9.032-74 *.

The anti-corrosion coating of metal structures and embedded parts after installation by welding must be restored by painting with two layers of PF-1331 enamel over a layer of GF-021 primer with a total thickness of at least 80 microns.

Apply a layer of primer to the weld seams with a brush or roller until the surface is completely primed.

The progress and results of work on applying anti-corrosion coating and painting must be entered in the Journal of works on waterproofing, anti-corrosion protection, painting of steel structures (form F-62, Rosavtodor order N IS-478-r dated 05.23.2002).

The completed work on the installation of a temporary support must be presented to the Customer's technical supervision representative for inspection and documentation by signing an Inspection Certificate for critical structures in accordance with Appendix 4, RD 11-02-2006.

This act must be accompanied by an as-built diagram of the support indicating its dimensions in plan and profile.

3.4.9. Temporary support is being installed scaffolding P1(see Fig. 12). The total weight of the metal of the P1 scaffolding is 780.2 kg, taking into account the weight of the welds 2% = 795.8 kg. The total volume of timber for scaffolding is 0.95 m.

Fig. 12. Scaffolding P1

The completed work on scaffolding must be presented to the Customer's technical supervision representative for inspection and documentation by signing an Inspection Certificate for critical structures in accordance with Appendix 4, RD 11-02-2006.

An as-built diagram of the scaffolding indicating its dimensions in plan and profile must be attached to this act.

3.4.10. The completion of preparatory work is recorded in the General Work Log (The recommended form is given in RD 11-05-2007) and must be accepted according to the Act on the implementation of occupational safety measures, drawn up in accordance with Appendix I, SNiP 12-03-2001.

3.5. Installation of the span

3.5.1. The construction of bridge spans is carried out in the following sequence:

Assembly of span beam blocks;

Arrangement of supporting parts;

Installation of beams in spans;

Securing beams against tipping;

Installation of the middle block of the orthotropic slab;

Combining beams and block into a span structure.

3.5.2. On the prepared slipway, the enlarged assembly of the blocks of span structures and the middle block of the orthotropic slab is carried out. The assembly joints of the main beams are assembled using high-strength M22 bolts.

The enlarged assembly of spans that are composite along the length should be carried out in the technological sequence determined by the installation project, according to the enlarged assembly maps, and also in strict accordance with the operating instructions for the installation units. Welding or tacking of mounting fixtures to the main structures is not allowed.

Workers who have undergone special training, confirmed by an appropriate certificate, can be allowed to make connections using high-strength bolts with controlled tension.

Before assembly, the contact surfaces of bolted joints must be inspected and cleaned of dirt, ice, loose rust, loose scale, oil, and paint (except for factory primer).

Hardware (bolts, nuts, washers) must be cleaned of factory preservative grease before being installed in connections.

Each high-strength class B and class A bolt of precision load-bearing type connections is equipped with one nut and two round washers - for the bolt head and one or two washers for the nut.

In connections where bolts are subject to shear and crushing, the bolt thread should be outside the hole, and the smooth part of the rod should not protrude from the washers.

Each tightened bolt must have at least one full thread remaining on the nut side.

The nuts of high-strength bolts, tensioned to the design forces, should not be secured with anything additional. In other bolted connections, the nuts are secured against loosening using spring washers in accordance with GOST 6402 or locknuts.

Connection bolts must be tightened first pneumatic impact wrench IP3112 with the highest tightening torque equal to 100 N*m to 50-90% of the design force, then tighten with a torque wrench to the design force with tension control based on the magnitude of the applied torque. The tightening forces of the bolts are controlled by the pressure in the pneumatic system.

Hydraulic torque wrenches of the KLTS type should be calibrated before their first use (or after repair), again after tensioning the first and second thousand bolts, and then periodically after tensioning every five thousand bolts. All torque wrenches in use must be numbered.

Manual torque wrenches should be calibrated at the beginning and in the middle of each work shift with a test weight. The results of their calibration should be entered into a special Logbook for the control calibration of wrenches for tensioning high-strength bolts in the form F-60, order of Rosavtodor dated May 23, 2002 N IS-478-r.

The tension of the bolts must be carried out from the areas with a tight fit of the parts of the package being connected to the areas with gaps. The bolts located near the plugs should be retightened after the plugs are removed. In connections with tightened bolts, no gaps are allowed between the plane of the structure, washers, nuts and bolt heads.

The quality of tightening of the bolts should be constantly checked by tapping them with a hammer weighing 0.4 kg, while the bolts should not shake or move. The results of the assembly of beams must be entered in the Logbook for installing high-strength bolts (form F-59, order of Rosavtodor dated May 23, 2002 N IS-478-r).

Fig. 13. General view of the enlarged block of the span =37.58 m

3.5.3. Movable supporting parts must be installed according to the design, taking into account the air temperature at the time of installation, as well as shrinkage and creep of the concrete of the spans. When installing supporting parts, marks should be applied to mark the relative initial position of their elements, and a mark indicating the temperature when installing spans.

3.5.4. Rubber and rubber-fluoroplastic supporting parts should be installed directly on under-truss platforms, prepared and verified within the deviations indicated in Table 1, and steel and glass ones - on a perimeter-formed layer of unset cement-sand mortar or polymer concrete indicated in Table 2.

It is permissible to install steel and glass support parts on wedges and adjusting devices, followed by injecting the gaps with epoxy resin-based glue and removing the wedges.

Before injecting the gaps, they should be sealed and fittings for injecting glue should be installed. At least four fittings must be installed around the perimeter of each supporting part. The fittings should be installed directly into the gap (when sealing it with a harness) or into holes specially provided by the design in the supporting parts.

Before installation, the rubbing surfaces of steel supporting parts and rolling surfaces must be thoroughly cleaned and rubbed with graphite or coated with molybdenum disulfide lubricant.

The installation of supporting parts is documented by an act of inspection and acceptance of the installed supporting parts.

3.5.5. Before installing spans and individual beams on supports using jib cranes, you must:

Preliminarily check the embankment of approaches, the condition of paths and platforms;

Strength and stability of previously installed structures;
funds will NOT be debited from your account and we will not receive payment confirmation.
In this case, you can repeat the purchase of the document using the button on the right.

An error has occurred

The payment was not completed due to a technical error, cash from your account
were not written off. Try waiting a few minutes and repeating the payment again.

Installation of long spans of reinforced concrete span structures Reinforced concrete prefabricated span structures of large length are mounted using various methods. 1. Mounted and semi-mounted assembly is used. 2. Longitudinal and transverse sliding. 3. Assembly on circles and scaffolds. 4. Installation of pre-assembled structures on shore on permanent supports by transporting them afloat.

Installation of large spans of reinforced concrete spans The method of assembling reinforced concrete spans depends on: the design of the bridge crossing; local conditions during work; Possibility of using inventory installation and process equipment.

Assembly of arches on inventory circles Installation of reinforced concrete spans of an arched system with a ride on top can be carried out on inventory circles, which are mounted on separate temporary supports, the gaps between which are covered by I-section beams. Devices are mounted under the beams, which are used for untwisting after the assembly is completed. Arched inventory circles consist of individual elements and mounting blocks connected by hinges in the form of bolts. The design of such circling devices is three-hinged with circling devices (hydraulic jacks or sandboxes) located in the lock. Laying of prefabricated arch blocks is carried out by cranes, the type and brand of which depends on the height of the bridge crossing and the weight of the mounted elements.

Installation of reinforced concrete arched prefabricated span structures with a ride on the bottom is carried out: 1. Directly in the span on a solid scaffold; 2. On the approach embankment followed by longitudinal sliding (if there is a stiffening beam); 3. In the span on intermediate separate supports with a stiffening beam assembly. 4. After assembly on piers or solid scaffolds built on the shore, subsequent transportation to the bridge span on floating supports.

Mounted assembly The most widespread in modern bridge construction is the suspended assembly of reinforced concrete bridge spans. The suspended installation method is most appropriate for reinforced concrete bridges, in which the load-bearing main structures operate under forces of the same sign both during operation and during installation. At wall-mounted prefabricated arches are supported by cables attached to masts mounted on supports.

Mounted assembly Assembly is carried out in the direction from the supports to the lock, after which the outline of the mounted arch is checked and the joints between the individual blocks are monolithic. To support the weight of the block installed by the crane, the joints are made rigid, ensuring the absorption of the bending moment and transverse forces arising from the weight of the mounted block.

Mounted assembly When carrying out mounted and semi-mounted assembly of reinforced concrete spans in accordance with SNi. The following requirements must be met:

Mounted assembly 1. Before starting assembly, the anchor block or several supporting anchor blocks, which determine the position in the profile and plan of the mounted console, must be carefully aligned and secured; 2. All elements and prefabricated blocks must be installed in strict accordance with the requirements of the PPR; 3. Placing any materials, equipment and structures not provided for in the project on the assembled consoles is strictly prohibited; 4. It is necessary to exclude any possibility of accidental impact of the mounted elements on already installed blocks;

Mounted assembly 5. Before concreting the closing blocks, it is necessary to make a reliable connection between the blocks to be joined. The slightest possibility of destruction of concrete in grouted joints due to thermal expansion and any deformation of assembled structures must be excluded; 6. Supporting the mounted console (with a continuous design) on two auxiliary supports is permitted as an exception, subject to mandatory constant monitoring on both supports of the value of the support reactions, designer supervision and personal supervision of the work of the chief construction engineer;

Suspended assembly 7. In addition to careful control over the tension and forces in the prestressing reinforcement, it is necessary to control the deflections of the assembled structure, the magnitude of possible displacements in the supporting parts and deformations of the concrete joints; 8. After installing continuous spans on the supporting parts and bringing the supporting block into the design position, the supporting parts must be blocked. Locking devices must allow adjustments in the profile and plan of the mounted structure. 9. Removal of blocking devices is carried out in strict accordance with the instructions of the PPR; 10. During the installation of structures with adhesive joints, it is allowed to tension the prestressed working reinforcement before or after the complete curing process adhesive composition; 11. Compression of adhesive joints during the installation of composite span structures must be performed immediately after uniform application of the adhesive over the entire section.

Construction of reinforced concrete bridges The type of crane and installation method are selected depending on the weight and dimensions of the elements being mounted, the width, depth and regime of the river, navigation conditions, terrain, time of year, the given construction period and the production capabilities of the construction organization. Bottom assembly using jib self-propelled cranes is convenient for the construction of overpasses, overpasses, and small bridges on dry land. For this purpose, general construction cranes on crawler or pneumatic wheels, as well as trailed cranes, are usually used. The soil in the area where the cranes are moving is leveled and compacted, for example, by rolling in the wheels or tracks of an unloaded crane.

The load-bearing capacity of the soil in the area of ​​operation of pneumatic wheel cranes must be no lower than 0.5 MPa, and for crawler cranes - 0.2 MPa. If the bearing capacity of the soil is insufficient, for example on swampy floodplains and in the riverbed, installation becomes significantly more difficult. It is necessary to arrange a working bridge for the movement of the installation crane and vehicles with elements of prefabricated spans, which slows down the pace of work.

When installing from the ground, jib cranes usually installed beams up to 21 m and weighing no more than 30-35 tons. The beam slinged with a traverse is lifted and inserted into the span by turning the crane boom, and then lowered onto the supporting parts with a cargo pulley, releasing the slings. In this case, the crane sequentially installs the beams, moving across the axis of the bridge. With a clear organization of work, it is possible to install structures “from wheels” without preliminary unloading and storage.

If the lifting capacity of one crane is insufficient, then two paired cranes are used. In this case, the beam is slung at its ends, lifted with cargo pulleys at the minimum reach of the booms and then, increasing their reach within the permissible lifting capacity of the cranes, they are inserted into the span. When installing span beams on overpasses across railway railway cranes are used.

Mounted assembly with a jib crane is advisable for installing span structures on bridges over permanent watercourses. This assembly is convenient and most economical, but is limited by the relatively small lifting capacity of jib cranes. The SKG 63 A crane, for example, can install in front of itself the beams of a road bridge 18 m long, weighing 14.3 tons with a permissible crane boom reach of 14 m. The peculiarity of overhead installation is that before installation of the beams, they are erected on the raft.

To ensure the stability of previously installed beams, before moving the crane and vehicles along them, the longitudinal joints of the beam slabs are first sealed. A wooden plank flooring is laid according to calculations, ensuring pressure distribution over several beams and protecting reinforced concrete slab from unacceptable loads. If the bridge roadway is wide enough, the beams are delivered directly to the crane on vehicles with trailers or trailers.

When sliding beams into a span over scaffolding, the overpass is made narrow, and the top is usually located at the level of the support crossbars. The beams of the span are installed on trolleys and moved along the bridge into the span using winches or other means. Then, by moving them transversely, they are installed in the design position. In this case, the beams are moved on other trolleys or slides along rails laid on the crossbars of adjacent supports or on auxiliary scaffolding along the support. Hydraulic jacks are used to lift beams when moving them from carts to supporting parts.

According to safety regulations, jacks are tested to double pressure, and during their operation, safety metal half-rings are placed between the jack head and the cylinder body.

The sluice crane GP 2 KhZO (Fig. 24. 12) ensures the installation of beams with a span of up to 33 m with a weight, taking into account slinging devices, no more than 60 tons. It consists of a longitudinal truss of triangular cross-section and three supports. The rear and middle supports of the crane are equipped with wheeled trolleys for longitudinal movement along the rail track. The track width of the crane track is 5.6 m. Self-propelled trolleys of the middle support are equipped with an electric drive. The crane's front support is equipped screw devices, ensuring the elimination of possible deflection and skew of the console and tight support on the under-truss area. P

For narrow bridges, it is possible to supply beams on narrow-gauge trolleys along rail tracks with preliminary reloading of the beams on the approaches. Gantry cranes, moved on the ground or along temporary overpasses, usually install multi-span precast reinforced concrete bridges and long and heavy beams of prefabricated spans. For this purpose, cranes are used that are assembled on a construction site from UICM elements (Fig. 24. 10) or manufactured by industry.

Manufacturing of prefabricated reinforced concrete structures Brief information about enterprises producing prefabricated reinforced concrete bridge structures. l Types of formwork, requirements for them. Basic technologies for manufacturing prefabricated reinforced concrete structures. Features of the manufacture of reinforced concrete beams using full-scale aggregate and bench technology with conventional frame-rod and pre-stressed reinforcement (with tension before and after concreting). Cassette manufacturing method. Quality control of reinforced concrete structures and acceptance of work. ts

Formwork types and applications Formwork system- a concept that includes formwork and elements that ensure its rigidity and stability, fastening elements, supporting structures, scaffolding. Formwork generally consists of: formwork - a form for monolithic structures; shield - a formative element of the formwork, consisting of a deck and frame; deck - an element of the shield that forms its forming work surface;

Types of formwork and areas of application formwork panel - a form-building flat formwork element consisting of several adjacent panels connected to each other using connecting nodes and elements and intended for formwork of the entire specific plane; formwork block - a spatial element closed around the perimeter, made entirely and consisting of flat and corner panels or panels.

Formwork material The formwork materials are steel, aluminum alloys, moisture-resistant plywood and wood boards, fiberglass, polypropylene with high-density fillers. The supporting elements of the formwork are usually made of steel and aluminum alloys, which allows them to achieve high turnover.

Main types of formwork. Formwork is classified according to functional purpose depending on the type of concrete structures: for vertical surfaces, including walls; for horizontal and inclined surfaces, including floors; for simultaneous concreting of walls and ceilings; for concreting rooms and individual apartments; for curved surfaces (mainly pneumatic formwork is used).

Collapsible and adjustable small panel formwork It consists of a set of small elements with an area of ​​up to 3 m2 and a weight of up to 50 kg, which allows you to install and disassemble them manually. The formwork elements can be used to assemble large panels and blocks that can be mounted and dismantled by crane without disassembling into their component elements. The formwork is unified and is applicable for a wide variety of monolithic structures with constant, variable and repeating dimensions.

Large-panel formwork Large-panel formwork consists of large-sized panels and connection elements. The formwork panels absorb all technological loads without installing additional load-bearing and supporting elements. Formwork is used for concreting extended walls, ceilings and tunnels. Large panel formwork is recommended for buildings with monolithic walls and partitions, prefabricated floors.

Large-panel formwork The size of the panels is equal to the size of the structure being concreted: for walls - the width and height of the room, for ceilings - the width and length of this ceiling. In the case of concreting large-area floors, when it is not possible to lay and compact concrete structures during one shift, the floor is divided into maps. The dimensions of the map are specified by technological regulations; a metal mesh with a thickness of 2. . is installed on their boundaries. . 4 mm with 10 x 10 mm meshes to ensure sufficient adhesion to subsequent cards.

Block formwork is a volumetrically adjustable formwork designed for the construction of three or four walls simultaneously along the contour of a building cell without a ceiling device. The formwork is assembled from separate blocks with gaps equal to the thickness of the walls being erected. For buildings with monolithic external and internal load-bearing walls and prefabricated floors, a combined option is recommended: for the external surfaces of the walls - large-panel formwork, and for internal surfaces and walls - block, vertically movable and removable formwork.

Block shapes are spatial closed blocks: one-piece and rigid, made into a cone, detachable or sliding (adjustable). The form block is used for concreting closed structures of relatively small volume, not only for vertical, but also for horizontal surfaces. In addition, they are used for volumetric elements of walls, elevator shafts, free-standing foundations, columns, etc.

Climbing formwork Climbing formwork consists (using the example of formwork for the construction of conical pipes) from panels of external and panel internal formwork, bearing rings (outer and internal), support frame, mechanisms for radial movement of outer formwork, working platform, external and internal scaffolding (suspended ).

Climbing formwork External formwork is assembled from rectangular and trapezoidal panels made of 2 mm thick steel sheet framed with corners. The panels are connected to each other by bolts passed through holes in the corners of the frame and a metal plate installed at the upper edge of the shield. The outer formwork also has end panels that close the formwork. To tighten the outer formwork, tie bolts are installed at the locations of the end panels.

Climbing formwork Internal formwork is assembled from two tiers of steel panels 1250 mm high, 550 mm wide and 2 mm thick. On the outside, strips with brackets are welded to the panels, which serve to insert spacer rods into them, ensuring rigidity and geometric immutability of the internal formwork. A horizontal bar with rings is attached to the upper edge of the shield for tying a rope when rearranging the shields. To connect adjacent panels in one tier, a metal plate is attached to the horizontal bar. When installing the upper shield on the lower one, the outer brackets overlap the horizontal bar. The internal formwork is closed using end panels that have one strip with brackets.

Volumetric adjustable formwork Volumetric adjustable formwork is a formwork consisting of sections that, when installed in the working position, form a U-shaped, L-shaped formwork in cross section for simultaneous concreting of walls and ceilings, as well as individual designs. The scope of application of volumetrically adjustable formwork is the construction of multi-storey monolithic buildings. Volumetric adjustable formwork is a large-sized formwork block, which includes formwork for walls and ceilings. The formwork block is assembled and rearranged using an assembly crane.

Volumetric adjustable formwork Volumetric adjustable formwork is divided into types according to the methods of installation and dismantling: formwork, the dismantling of which is carried out in the horizontal direction, is used in the construction of multi-story buildings. With the help of such formwork, walls and ceilings are simultaneously concreted and then dismantled special devices and installed on the next floor. formwork, the dismantling of which is carried out in the vertical direction, is used in the construction of buildings with longitudinal and transverse walls. This formwork is used for concreting internal and external walls with further dismantling upwards.

Volumetric adjustable formwork There are two types of volumetrically adjustable formwork: volumetric adjustable formwork of a frame structure, which consists of a supporting frame with mounted movable side panels and an installed movable horizontal panel; Volumetrically adjustable formwork of a frameless design consists of sections of side and horizontal panels. The panels are equipped with struts and trusses to increase rigidity.

The formwork must meet the following requirements: be strong, stable; do not change shape under the influence of loads arising during the production process; the deck (cladding) of the formwork panel must be sufficiently dense, there should be no gaps in it through which cement mortar can leak; ensure high quality surfaces, eliminating the appearance of sagging, cavities, curvatures, etc.; be technologically advanced, i.e. it must be installed and disassembled, not create difficulties during the installation of fittings, as well as during laying and compaction concrete mixture;

The formwork must meet the following requirements: have turnover, that is, be reusable; the higher the turnover of the formwork, the lower its cost per unit volume of the finished structure.

The practice of domestic mass industrial and civil construction has been developed and successfully uses a number of structurally different formworks, greatest distribution of which, for certain areas of application, the following types were obtained: collapsible, adjustable - for the construction of massifs, foundations, walls, partitions, columns, beams, roofing and floor slabs, block - for the construction of free-standing foundations and fragments of large-sized structures, lifting, adjustable - for the construction of structures high altitude constant and with changing cross-section geometry, volumetrically adjustable - during the construction of walls and floors of buildings, sliding - during the construction of vertical structures of buildings and structures of great height, horizontally movable - during the construction of linearly extended structures, non-removable - during the construction of structures without stripping, with a waterproofing device , cladding, insulation, etc.