We provide delivery to any region of the Russian Federation. We fulfill our delivery obligations regardless of the size of the shipment and the number of commodity items, the destination and the state of the transport network in the addressee’s region.
Prom ZhBI sends tens of tons of reinforced concrete products every day to different parts of the country. Our regular customers are large contracting organizations from Kaliningrad and Vladivostok, Arkhangelsk and Belgorod, Nizhny Novgorod and Astrakhan. The consistency of orders placed by construction companies and operating organizations at Prom-ZhBI is due to:
- our compliance with delivery conditions (deadlines, nomenclature and quantity of concrete products)
- efficiency in order processing
- compliance with the rules for transporting reinforced concrete products
- vast experience in organizing the transportation of reinforced concrete products, which allows you to avoid force majeure along the way
- well-functioning logistics system (we choose the most convenient and inexpensive delivery options)
With us you will always receive your ordered materials on time. We organize delivery of any goods manufactured in our production.
The low price for the entire range of products manufactured by the company is complemented by affordable delivery costs. At the same time, the Prom-ZhBI company takes upon itself all organizational efforts. We control:
- order completion and shipment
- route and travel time
- delivery time to the destination and order completeness at the unloading point
Regardless of the region in which you are located, delivery is organized as quickly as possible: no matter where you expect the cargo, it will arrive to you on time and without any effort on your part.
During the construction of pipelines, the reinforced concrete head performs several important functions. It ensures uniform movement of fluid through the pipeline due to uniform inclination, supports slopes and protects gaps from falling asleep with soil.
You can purchase reinforced concrete pipe heads from our company in a wide range. We offer several size options and guarantee excellent quality. The culvert head helps to increase the durability of pipelines and ensures their long-term trouble-free operation. We offer reinforced concrete products that have a number of advantages:
- High strength. It allows the product to withstand heavy mechanical loads.
- Resistance to temperature changes and minimal water absorption. These factors will allow you to withstand destructive environmental factors for a long time.
- Any reinforced concrete head undergoes multi-stage control, so we guarantee the absence of defects and maximum reliability.
The price of a reinforced concrete head of any size will be favorable, you can get the necessary information by calling us. We offer to place an order with delivery of products to the regions, please contact us!
We offer to buy OG heads
When constructing culverts, reinforced concrete flue caps are indispensable products. They are classified as reinforced concrete products for reclamation purposes, since they are designed to protect the road from atmospheric phenomena affecting it. Reinforced concrete OG heads are L-shaped elements that can be of different sizes.
Exhaust pipe caps are a necessary element to strengthen the roadside and prevent destruction. Our reinforced concrete plant offers high-quality exhaust caps made of heavy concrete, which has excellent strength characteristics.
TYPICAL TECHNOLOGICAL CARD (TTK)
PRODUCTION OF WORKS ON THE CONSTRUCTION OF A PRECASTIC CULVER WITH AN HOLE OF 3.0x2.0 m WITH MONOLITHIC ENDS
I. SCOPE OF APPLICATION
I. SCOPE OF APPLICATION
1.1. A standard technological map (hereinafter referred to as TTK) is a comprehensive regulatory document that establishes, according to a specific technology, the organization of work processes for the construction of a structure using the most modern means of mechanization, progressive designs and methods of performing work. The TTK is designed for some average conditions of work. The TTK is intended for use in the development of Work Projects (WPP), other organizational and technological documentation, as well as for the purpose of familiarizing (training) workers and engineers with the rules for carrying out work on the construction of reinforced concrete, prefabricated culvert with a hole of 3.0x2.0 m with monolithic caps for the embankment of the highway.
1.2. This map provides instructions for the construction of a culvert using rational means of mechanization, provides data on quality control and acceptance of work, industrial safety and labor protection requirements during the production of work.
1.3. The regulatory basis for the development of a technological map is: SNiP, SN, SP, GESN-2001 ENiR, production standards for material consumption, local progressive standards and prices, labor cost standards, material and technical resource consumption standards.
1.4. The purpose of creating the TC is to describe solutions for the organization and technology of construction work in order to ensure their high quality, as well as:
- reducing the cost of work;
- reduction of construction duration;
- ensuring the safety of work performed;
- organizing rhythmic work;
- unification of technological solutions.
1.5. On the basis of the TTK, as part of the PPR (as mandatory components of the Work Project), Working Technological Maps (RTC) are developed for the implementation of certain types of work on the construction of a culvert. Working technological maps are developed for the specific conditions of a given construction organization, taking into account its design materials, natural conditions, the available fleet of machines and building materials tied to local conditions. Working technological maps regulate the means of technological support and the rules for performing technological processes during the production of work. Design features for the construction of a culvert 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.
Working flow charts are reviewed and approved as part of the PPR by the head of the General Contracting Construction Organization, in agreement with the Customer's organization, the Customer's Technical Supervision.
1.6. The technological map is intended for work producers, foremen and foremen performing construction work, as well as technical supervision workers of the Customer and is designed for specific conditions of work in the third temperature zone.
II. GENERAL PROVISIONS
2.1. A technological map has been developed for a set of works for the construction of a culvert.
2.2. Work on the construction of a culvert is carried out in one shift, the duration of working hours during a shift is:
Where 0.828 is the coefficient of use of mechanisms over time during a shift (time associated with preparation for work and carrying out technical maintenance - 15 minutes, breaks associated with the organization and technology of the production process and driver rest - 10 minutes every hour of work).
2.3. The work performed sequentially during the construction of a culvert includes:
- preparatory work;
- marking works;
- excavation;
- installation work (installation of the outlet head, installation of the foundation for the pipe body, installation of pipe sections, installation of the inlet head);
- waterproofing works;
- strengthening works.
2.4. The technological map provides for the work to be carried out by an integrated mechanized unit with automobile jib crane KS-4561A(see Fig. 1 and Fig. 2) with a lifting capacity of 25.0 tons as a driving mechanism.
Fig.1. General view of the KS-4561A truck crane
Fig.2. Height and load characteristics of the KS-4561A crane
2.5. Work should be performed in accordance with the requirements of the following regulatory documents:
- SP 48.13330.2011. Organization of construction;
- SNiP 3.01.03-84. Geodetic work in construction;
- SNiP 3.02.01-87. Earthworks, bases and foundations;
- SNiP 3.06.04-91. Bridges and pipes;
- SNiP 3.03.01-87. Load-bearing and enclosing structures;
- SNiP 3.04.01-87. Insulating and finishing coatings;
- SNiP 3.04.03-85. Protection of building structures from corrosion;
- Manual for SNiP 3.02.01-83*. A manual for the execution of work when constructing bases and foundations;
- VSN 32-81. Waterproofing of bridges and pipes;
- SNiP 12-03-2001. Occupational safety in construction. Part 1. General requirements;
- SNiP 12-04-2002. Occupational safety in construction. Part 2. Construction production;
- RD 11-02-2006. Requirements for the composition and procedure for maintaining as-built documentation during construction, reconstruction, major repairs of capital construction projects and requirements for inspection reports of work, structures, sections of engineering support networks;
- RD 11-05-2007. The procedure for maintaining a general and (or) special log of work performed during construction, reconstruction, and major repairs of capital construction projects.
III. ORGANIZATION AND TECHNOLOGY OF WORK EXECUTION
3.1. In accordance with SP 48.13330.2011 “Construction Organization”, before the start of construction and installation work at the site, the Contractor is obliged to obtain from the Customer in the prescribed manner design documentation and permission to carry out construction and installation work. Carrying out work without permission is prohibited.
3.2. Before the start of work on the construction of a culvert, it is necessary to carry out a set of preparatory work and organizational and technical measures, including:
- appoint persons responsible for the quality and safety of work;
- conduct safety training for team members;
- place the necessary machines, mechanisms and equipment in the work area;
- arrange temporary driveways and entrances to the work site;
- provide communication for operational dispatch control of work;
- install temporary inventory household premises for storing building materials, tools, equipment, heating workers, eating, drying and storing work clothes, bathrooms, etc.;
- provide workers with tools and personal protective equipment;
- prepare places for storing materials, inventory and other necessary equipment;
- fence the construction site and put up warning signs illuminated at night;
- provide the construction site with fire-fighting equipment and alarm systems;
- draw up a report on the readiness of the facility for work;
- obtain permission to carry out work from the Customer’s technical supervision.
3.3. Before the construction of the pipe begins, the following activities and work must be completed:
- a construction site prepared for work has been accepted from the customer;
- construction materials, necessary equipment, tools, reinforced concrete pipe sections were delivered and stored;
- entrances and exits from the site have been arranged;
- water drainage from the work site is ensured;
- a geodetic breakdown of the pit contour was carried out.
3.4. Reinforced concrete structures delivered to the construction site (see Fig. 3) are unloaded from vehicles using a KS-55713-4 truck crane.
Fig.3. Construction site plan
1 - fittings; 2, 3 - lumber warehouse; 4 - path of movement of the crane; 5 - warehouse block of pipe links; 6 - container with cement; 7 - concrete mixer; 8 - water tank; 9 - power plant; 10 - crushed stone warehouse; 11 - sand warehouse
The pipe sections delivered to the construction site are laid in one tier on a sand bed. Throwing pipe sections from vehicles or into pits is prohibited. The pipes are laid along the pipe pit, in accordance with the technological installation sequence, leaving a berm at least 4.0 m wide for the crane access.
The mounting loops on the pipe body links are cut off flush with the concrete surface by electric welding before the pipe is installed. cutting off hinges with a chisel or bending them is not allowed.
To ensure the drainage of water from the work site, the existing watercourse is directed to bypass the installation site - the pit under the pipe body.
3.5. Geodetic alignment works
3.5.1. The geodetic layout of the pit consists of marking it on the ground. The breakdown is carried out in two planes: horizontal and vertical. When laying out horizontally, the position of the axes is determined and fixed on the ground, and when laying out vertically, the estimated depth of laying the pipe.
3.5.2. Laying out a pit for a pipe begins with finding and securing the longitudinal axis of the pipe, performing the following steps:
- restore the road axis;
- measure with a steel tape (twice) the distance from the PC to the longitudinal axis of the pipe along the axis of the road;
- hammer a steel nail 100-120 mm long into the resulting point;
- center the theodolite over the nail and transfer to reality the angle between the axis of the pipe and the axis of the road;
- secure the resulting longitudinal axis of the pipe with four control posts, two on each side, installed no closer than 3 m from the boundaries of the pit;
- transfer the mark of the nearest benchmark to the control posts, as well as the marks of the pipe inlet and outlet trays;
- check the compliance of the future channel of the drainage ditch with the project;
- break out the outlines of the pit according to the layout drawing, securing its contours. To do this, cast-offs are installed parallel to the axes of the pit at a distance of 2-3 m from its boundary (see Fig. 4), the position of which is recorded in the layout drawing. On the cast-offs, use a tape measure to mark the main axes of the pipe, fixing them with marks and corresponding inscriptions.
Fig.4. Inventory cast-off
2 - steel wire string; 3 - plumb line
3.5.3. The surveyor, using a theodolite, transfers the axle alignments to the upper edge of the cast-off and secures them with marks. The breakdown of places where scratches are applied is carried out using the method of opening serifs from the axes X And Y center grid available in the working drawings. Per relative mark 0,000
The elevation of the top of the pipe was adopted corresponding to the absolute elevation available on the general plan. The position of the centering axes of the pipe is fixed with steel wire strings stretched on a cast-off. Then they are transferred to the surface of the platform using plumb lines lowered from the stretched strings and this point is secured with metal pins. The accuracy of the planned pit layout must be within 5 cm. The securing marks (pegs with marks) are retained until the pipe is put into operation by the customer. Alignment points damaged during the work must be immediately restored.
The accuracy of marking work must comply with the requirements of SNiP 3.01.03-84 and SNiP 3.02.01-87. The diagram for the production of geodetic pit layout is shown in Fig. 5.
Fig.5. Scheme of production of geodetic pipe laying
3.6. Pit development
3.6.1. The development of a pit for the pipe body and head is carried out single-bucket excavator ET-16(see Fig. 6), a special swamp modification, the pressure of which on the ground does not exceed 20-25 kPa, having a widened and elongated caterpillar track. Detected underground water outlets into the pit (springs, springs, etc.) are plugged with a clay plug.
Fig.6. Excavator ET-16
Cleaning and leveling of the bottom of the pit to the design marks (5-10 cm) is carried out manually, under the lath, taking into account the design slope and a given construction rise equal to 1/50 of the embankment height, immediately before the foundation is laid.
The excavated soil is placed in a dump and then removed beyond the construction site. The bottom of the pit is compacted vibrating plate LF-70, up to 0.95.
A break between the completion of the pit development and the installation of the foundation for the pipe body is, as a rule, not allowed.
If the construction of the foundation is delayed, it is necessary to develop the pit short of the design mark, and cover the pit itself with heat-insulating material. When using peat (0.16-0.18 g/cm), layout, leveling and compaction are done manually. Insulating blocks made of aerated concrete, polystyrene foam, etc. laid with a truck crane. The completed work is presented to the Customer for signature on the construction of the pit, in accordance with Appendix 3, RD-11-02-2006.
3.7. Installation of a monolithic concrete foundation slab for the pipe body
3.7.1. Under prefabricated reinforced concrete pipe sections, it is necessary to build a foundation in the form of a monolithic slab of concrete class. B20, W6, F150 0.20 m thick per layer crushed stone M 800 fraction 20-40 mm thickness 0.10 m.
Crushed stone is being delivered front loader VOLVO L-45B(bucket capacity 1.2-2.5 m), leveled by hand, compacted vibrating plate LF-70D up to no less than 0.95.
The completed work is presented to the Customer for signing inspection reports of hidden work on the installation of a “cushion”, in accordance with Appendix 3, RD-11-02-2006.
3.7.2. To install a monolithic concrete slab, a prefabricated formwork 20 cm high is installed on the finished “cushion”. The marking of the formwork installation sites is carried out using the method of opening notches from the axial points of the pipe. The anchor points are fixed to cast-offs located outside the work area. Per relative mark 0,000
The elevation of the top of the pipe was adopted, corresponding to the absolute elevation indicated on the general plan. The formwork is assembled from edged softwood lumber from the 6th century. 40-50 mm thick and bars 40x40 (50x50) mm. On the inside, the boards are fixed to the required size with spacers, and on the outside with stakes driven into the ground close to the boards, which, just like the boards, perceive the lateral pressure of the concrete mixture.
3.7.3. Wooden “beacons” 30 mm high are installed on the compacted crushed stone “cushion” and on them, to give strength to the monolithic foundation, meshes of reinforcing steel A-III, grade 35GS, with a diameter of 12 mm, with a cell pitch of 100x100 mm, are laid. The grids are laid with an overlap of at least 25-30 reinforcements. The mesh is connected by tying the joint in three places (in the middle and at the ends) with knitting steel wire with a diameter of 0.8...1.0 mm using special hooks.
The reinforcing mesh is supplied to the work area using a truck crane. Manual installation is allowed only if the weight of the reinforcement elements is up to 20 kg.
3.7.4. The process of laying concrete mixture consists of work operations associated with feeding it into the formwork and compaction. Before laying the concrete mixture into the formwork, you must check:
- formwork fastening elements;
- quality of cleaning the formwork from debris and dirt;
- quality of cleaning of fittings from rust deposits;
- carrying out the axes of the structure (with paint) onto the reinforcement frame;
- use slats or tow to seal large gaps in the formwork;
- cover the internal surfaces of the formwork with polyethylene film to reduce the adhesion force of concrete to boards;
- present the finished formwork and installed reinforcing mesh with outlets to the Customer for inspection and signing of the Certificate for hidden work on the installation of formwork and installation of the reinforcement cage, in accordance with Appendix 3, RD-11-02-2006.
3.7.5. The concrete mixture is delivered to the site concrete mixer trucks SB-049A(4.0 m) and unloaded into rotating tubs with a capacity of 0.8 m located within the range of the crane, after which the tub is installed in a vertical position using a truck crane, transported to the laying site and unloaded into the formwork.
3.7.6. When laying the concrete mixture, you must follow the basic rules:
- adding water when laying the concrete mixture is not allowed;
- cold water separated from the mixture must be removed;
- the height of free dumping of the concrete mixture should not exceed 1.0 m.
When laying the concrete mixture, it is necessary to provide protection of the structure being manufactured from precipitation with polyethylene film.
Stripping a concreted structure and loading it with pipe links is allowed when the concrete reaches a strength equal to at least 75% of the design strength.
3.8. Monolithic head structure
3.8.1. Operations for constructing monolithic concrete heads are performed in the following order:
- a pit is being developed for the portal wall and slope wings;
- install the formwork of the portal wall with the adjustment of the panels and their fastening;
- install the formwork of the left slope wing with plumb alignment and fastening;
- install the formwork of the right slope wing;
- take the concrete mixture from a bucket supplied by a truck crane;
- place the concrete mixture into the formwork and compact it with a vibrator;
- smooth the exposed surface of the freshly laid mixture;
- maintain concrete.
3.8.2. The excavation for the heads is being developed single-bucket excavator ET-16. Cleaning and leveling the bottom of the pit to the design marks (5-10 cm) is done manually. The excavated soil is placed in a dump and then removed beyond the construction site. The bottom of the pit is compacted vibrating plate LF-70, up to 0.95. Crushed stone is poured into the pit under the head with a design layer, taking into account the safety factor for compaction equal to 1.25, leveled and compacted with a vibrating plate.
3.9. Installation of collapsible formwork under the heads
3.9.1. Formwork is used to give the required shape, geometric dimensions and position in space of the erected heads (portal wall and slope wings) by laying the concrete mixture into the volume limited by the formwork.
3.9.3. Formwork panels are made from edged lumber 50 mm thick, 100 mm wide and wooden blocks 50x50 mm. The front parts of the boards in contact with the concrete are sheathed with waterproof, bakelite, laminated plywood 16 mm thick (FBS-16), secured to the boards with self-tapping screws.
3.9.4. For concreting the heads, collapsible formwork is used. Collapsible formwork is assembled from ready-made elements - panels. The assembly of formwork panels is carried out at the installation site in a certain sequence:
- the boards are laid with the working surface down, wooden slats are placed in the places where mounting and working fasteners are installed;
- check the overall dimensions of the shields, nail limiting wooden bars along their contours;
- the boards are connected to each other with wooden overlays;
- holes with a diameter of 18-20 mm are drilled in wooden slats in places where the ties pass;
- wooden scrums are laid out on top of the shields;
- fights with shields are connected with nails or staples;
- rigidity bonds are laid on top of the contractions perpendicular to them, for which the same contractions are used;
- struts are attached to the lower tiers of the contractions or stiffeners, ensuring the stability of the panels in a vertical position.
3.9.5. Installation of formwork panels in the design position is carried out according to the marks marked on the crushed stone preparation according to the alignment axes fixed on the cast-off, with simultaneous alignment of the verticality of the panels along the alignment axes with theodolites.
The formwork installation site is cleared of wood chips, debris, snow, and ice. When installing shields, you need to ensure that they are tightly connected to each other. When installing the formwork, it is necessary to ensure its stability with the help of racks, resting them on a solid base and securing them with spacers.
Prefabricated reinforced concrete pipes, depending on the cross-section, are divided into round cylindrical, round with a flat base, rectangular and ovoid (Fig. 7.4).
Circular culverts used when the embankment height is predominantly no more than 8 m. Round pipe links under railway embankments rest on shallow or deep foundations, prefabricated, prefabricated monolithic or monolithic. The design of the pipe foundation depends on the bearing capacity of the foundation soil. g - ovoidal; new; prefabricated reinforced concrete pipes: a - round, rectangular and ovoid, fig. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
When supporting a round cylindrical link on a flat foundation, a pattern block is used (Fig. 7.5).
Reinforcement cage of round links consists of two rows (external and internal) of working spiral reinforcement, transverse reinforcement - clamps, as well as distribution longitudinal reinforcement (Fig. 7.6).
Rice. 7.6. Diagram of the reinforcing cage of a round pipe for a link 1 m long: A– cross section; b– view 1-1 and facade; V– spiral; d k– frame diameter; d H k , d B k– diameter of the location of the outer and inner spirals
The reinforcement cage consists of the same number of spirals located along the outer and inner contours of the link, which is determined by calculation. The Lengiprotransmost Design Institute has developed the following standard designs for reinforced concrete round pipes:
№GS 3.501.1-144– round reinforced concrete culverts for railways and roads;
№GS 3.501.1-144. Issue 0-1. Inv. No. 1313/2– round reinforced concrete culverts with flat support for railways in normal climatic conditions.
Z
Rice. 7.7. Reinforcement scheme for a round link with a flat base: A– cross section; b– view along the pipe axis; d kv ,
d book– diameters of internal and external frames
Links round pipes with flat base have more economical reinforcement, the diagram of which, according to the developments of Lengiprotransmost, is presented in Fig. 7.7.
Design of inlet and outlet heads reinforced concrete Round pipes are assumed to be the same from the unification conditions. The heads consist of slope walls (wings), located at an angle to the pipe axis, and portal walls (Fig. 7.8).
Reinforcement frame of slope wings made from meshes (Fig. 7.9).
Rice. 7.8. Round pipe head design: A– façade; b – section along the pipe axis; V - plan (embankment not shown); 1 – conical link; 2 – portal wall, 3 – slope wall; 4 – pattern block; 5 – foundation
Rice. 7.9. Design of the reinforcement frame of the slope wings of the round pipe head: A - facade; b – plan
The slope walls of the heads are installed on reinforced concrete slabs laid on crushed stone or gravel-sand preparation. A concrete tray is placed between the slope wings on a gravel-sand preparation (see Fig. 7.8).
WITH
Rice. 7.10. Diagram of a rectangular reinforced concrete pipe section: A– cross section; b– cut along the pipe axis
The standard design provides for an increase in elevated links by 0.5 m compared to normal ones. The following standard designs of prefabricated reinforced concrete pipes of rectangular cross-section have been developed:
№GS 3.501-177.93– reinforced concrete rectangular culverts for railways and highways (JSC Transmost, 1994);
№GS 3.501-177.93. Issue 0-2– rectangular pipes for railways in moderate and severe climatic conditions (JSC Transmost, 1994);
№GS 3.501-107. Inv. No. 1130/1.2– rectangular concrete culverts for railways and roads.
Reinforcement frame of a rectangular pipe link includes meshes consisting of working and distribution reinforcement, located along the external and internal contours, taking into account the provision of a protective layer of concrete, which are combined using clamps (Fig. 7.11).
Rice. 7.11. Reinforcement frame diagram of a rectangular link: A– cross section; b– view along the pipe axis
In the middle part of typical pipe structures, the length of the sections is 2.01 and 3.02 m. The links rest on the foundation along a layer of cement mortar. The foundations of the sections can be monolithic, prefabricated reinforced concrete or concrete blocks, shallow or deep. An expansion joint 3 cm thick is installed between the sections.
In reinforced concrete pipes of rectangular cross-section, they are used bell heads with sloped wings located at an angle of at least 20° (Fig. 7.12).
On railways built in areas with harsh climatic conditions, rectangular reinforced concrete and concrete culverts are most common. Currently, standard designs of rectangular pipes for harsh climatic conditions have been developed:
№GS 3.501.1-177.93. Issue 0–3. Pipes for railways and roads in particularly harsh climatic conditions. (JSC Transmost, 1994);
№GS 3.501-65. Inventory No. 1016. Culverts for railways and roads at a design temperature of minus 40 o C and below, deep seasonal freezing and ice dams. Rectangular concrete pipes. (Lengiprotransmost, 1976).
Rice. 7.12. Design of the outlet head of a rectangular pipe: A - facade; b – section along the pipe axis; V - plan (embankment not shown)
Links rectangular reinforced concrete pipes used with a hole from 1.5 to 6.0 m. They are based on prefabricated monolithic foundations, consisting of prefabricated reinforced concrete blocks of L- or T-shape (Fig. 7.13, 7.14) and monolithic concrete, as well as deep foundations on piles and pillars (Fig. 7.15, 7.16).
Rice. 7.13. Rectangular reinforced concrete pipe with L-shaped and T-shaped foundations: A - section cross section; b– head façade
Rice. 7.15. Rectangular reinforced concrete pipe with foundations on piles and pillars: A - head; b, c – cross section of sections
Rice. 7.16. General view of a rectangular reinforced concrete pipe with foundations on piles
Concrete rectangular pipe structures used with a hole from 1.5 to 6.0 m, which provide a water throughput capacity of up to 150 m 3 /s. The middle sections of the pipes are 3–4 m long. The structures of such pipes consist of reinforced concrete floor slabs, concrete wall blocks, nozzles, a tray and a foundation (Fig. 7.16, 7.17). Pipes with a hole of 1.5–3.0 m have solid foundations, and the rest are separate on a natural foundation, monolithic, prefabricated, and also deep laid on piles or pillars. The trays are concreted using sand preparation. The pipes have bell-shaped ends with increased inlet and normal outlet links.
Typical concrete culverts have similar foundations to reinforced concrete ones (Fig. 7.17, 7.18).
Rice. 7.17. Rectangular concrete pipes: a, b – cross section of section and head; V - with L-shaped and T-shaped foundations
In the typical design of rectangular culverts, foundations made of reinforced concrete blocks of L-shaped and T-shaped sections are provided for a freezing depth of the foundation soil equal to 2.3 and 4 m.
In harsh climatic conditions, in the presence of thawed and soft soils at the base, it is preferable to install the outer sections and head openings on pile foundations (see Fig. 7.16). The use of pile foundations increases the rigidity of the base and protects pipes from stretch marks. In case of weak foundation soils, it is advisable to use foundations with inclined piles in the outer sections and head openings.
When constructing culverts on permafrost soils, the natural regime of the foundation is maintained without disturbing natural conditions. In this case, preference is given to pipes with foundations on drilled columns with a diameter of 0.6–0.8 m (see Fig. 7.15, V).
Rice. 7.19. Design of the head of a concrete pipe with an ovoid cross-section: A - cross section; b– façade; 1 – opener section; 2 - general form
Structures of concrete and reinforced concrete pipes ovoid section used with a hole from 1.0 to 3.0 m (Fig. 7.19, 7.20). Reinforced concrete links of ovoidal pipes have reinforcement in the form of closed spirals (Fig. 7.21).This type of reinforcement cage ensures reliable operation of the structure taking into account the full range of loads. All sections of ovoidal pipe links operate as eccentrically compressed elements.
The use of concrete ovoidal pipes makes it possible to reduce the labor intensity of factory production and the consumption of reinforcing steel. They are used for embankment heights of up to 20 m.
Reinforced concrete pipes with an ovoid cross-section are more efficient structures when compared with round structures in terms of reinforcement consumption on average up to 40–45%.
When constructing culvert systems under roads and railways, slope wings and portal walls are used, which form heads for pipes. In essence, this is a complex reinforced concrete structure consisting of several main parts. At the end points of pipeline systems, caps are installed that act as safety and reinforcing elements. The main structural element is the portal wall, framed by sloped wings.
The material used in the production of pipe heads is concrete, used in monolithic structures. Standards and requirements are regulated by TPR 503-7-015.90 for socketed products and series 3.501.1-144 for round pipes. Conical heads are solid structures made of reinforced concrete, including a pipe link and a portal wall (ZKP 11.170 - 1 m diameter, ZKP 12.170 - 1.25 m diameter, ZKP 13.170 - 1.5 m diameter). The production of pipe heads can be carried out by a specialized enterprise that has sufficient material and technical capabilities. Due to the fact that there are not many such factories, sometimes there is a shortage of products, this is mainly observed in the spring and summer. Transportation of pipe heads is carried out using trucks. In some cases, the use of special transport is required, for example, when loading slope walls to large pipe sections (1,200 mm diameter).
Serial production of heads
At the enterprises, the production of heads is carried out in accordance with the existing standard documentation on pipe elements of culvert systems. The production of portal walls and slope wings is carried out separately. Concrete grades are selected in accordance with the specific purpose of the product.
