In 1964, a bridge across the Don River was put into operation in the city of Aksai. The city of Aksai is located in the suburb of Rostov-on-Don, on the steep right bank of the Don, at the confluence of the Aksai River, which is a branch of the Don (Fig. 1).

The bridge crossing is located at km 1061 + 570 of the 1st category motorway M-4 "Don" Moscow - Voronezh - Rostov - on - Don - Krasnodar - Novorossiysk.

The bridge was built in the period from 1958 to 1964 according to the project of the Tbilisi branch of "Soyuzdorproekt" under loads of N - 18 and NK - 80. The fundamental design document "Rules and indications for the design of reinforced concrete, metal, concrete and stone artificial structures on highways" edition 1948 G.

The superstructure project was developed by the Proektstalkonstruktsiya Institute. The project for the installation of the bridge superstructure was developed by the Institute "Prometallkonstruktsiya", Moscow.

In the bridge crossing scheme, there are five spans covered with a continuous steel-reinforced concrete superstructure according to the scheme 65.59 + 126.0 + 147.0 + 126.0 + 65.59m. The total length of the structure is 545.83 m (Fig. 2). The width of the bridge between the railings is 10.02 m. The main beams are welded with bolted mounting joints.

In span 1-2 there are two main tracks of the electrified railroad and one dead-end track. (Figure 3).

The span of the bridge 3-4 is navigable with heavy traffic. The navigable passage in the area of ​​the bridge belongs to the seaport "Taganrog".

The underbridge clearance from the water surface is 19.8 - 21.5 m, and from the rail head is 13.5 m.

During operation, repeated inspections and tests of the superstructure were carried out. The last survey at the pre-design stage of reconstruction was carried out in 2007 by MGUPS (MIIT), which provides a detailed description of the main results of previous surveys, basic information about the operation of the structure and repair measures that were carried out during the operation period.

The occurrence of significant defects during the operation in the elements of the structure is associated with two circumstances: with the overload of the superstructure with constant loads from the extra layers of the pavement of the driving bed; moving support No. 1, which is caused by landslides on the slope of the right bank of the Don River.

During the construction of the bridge from 1958 to 1964, work was carried out that introduced many uncertainties in the general stress-strain state of the structure and sharply complicated the assessment of the technical condition of the bridge. At the final design stage, the size of the roadway was increased from G-7.0 to G-8.0 without changing the design solutions of the main metal structures. In order to improve the longitudinal profile, an additional layer of concrete of variable thickness was laid at the supports in the 147 m span, as well as in the outer spans. The longitudinal profile of the upper chords of the main beams and the slab of the roadway during the construction period was corrected by laying an additional layer of concrete and asphalt concrete on the slab of the roadway in the places of "failures". For this purpose, in spans 1-2, 3-4, 4-5, a layer of variable thickness was added with a total volume of about 170 m3.

In the course of repeated studies and measurements of the stress-strain state of steel beams, it was determined that in the sections above the supports 3, 4 and 5, the stresses in the upper chords of the beams exceeded the calculated ones. The magnitude of the overvoltage, approximately, reaches 15 - 20% (data from VISI, TsNIIS, Institute "IES Paton").

In 2010, RTF Mostootryad-10 carried out work to eliminate the emergency at the bridge crossing, the work consisted of the following:

- trimming the ends of the steel structures of the superstructure, the ends of the spans were rested against the cabinet wall;

- lifting the superstructure with adjusting the position of the supporting parts on the support No. 1;

- installation of supporting structures under the sidewalk blocks in the navigable part of the bridge in order to keep them from spontaneous collapse. The supporting consoles of the sidewalk blocks were in disrepair, the blocks were held by the railings and abutment against each other.

Based on the report of MGUPS (MIIT), it was decided to dismantle the bridge.

The superstructure is steel-reinforced concrete continuous beam. In cross-section, the superstructure consists of four main I-beams of variable height. The distance between the main beams is 2.4 + 3.0 + 2.4.

The material of the main beams and jack beams is 10G2SD, ties and other elements from St3. Welding of elements made of low-alloy steel was carried out automatically, assembly joints were made on rivets with a diameter of 23 mm from steel 2, 26 mm from steel NL-1.

The main beams are interconnected by a precast-monolithic reinforced concrete slab of the roadway, longitudinal (in pairs, beams 1 and 2, 3 and 4) and cross ties. The main beams in the end spans at the extreme supports have a height of 2.5 m.On the rest of the extreme spans, the height of the beams gradually increases and on the supports reaches 4.6 m. In the middle part of the three main spans, the height of the beams is 2.5 m. On the supports of the middle span, the height of the beams 6.549 m (Fig. 4).

Steel main beams above supports 2, 3, 4 and 5 are prestressed at the level of the upper chords with bundles of high-strength wires. The tensile strength of wires is R = 17000 kgf / cm2. Bundles of high-strength wire are made in the form of ropes of three strands of seven strands of 0.5 mm and three separate wires of 0.5 mm. The tension of the beams was carried out with double-acting jacks, after which the beams were fixed with the help of anchor plugs and blocks on special stops welded to the upper chords of the beams.

The length of the prestressing zone above supports 2 and 5 is 51.5 m, and above supports 3 and 4 about 103.4 m.

The beams are homogeneous when concreting the roadway slab.

The roadway slab consists of three types of precast concrete slabs. The slab thickness is 15 cm, made of concrete grade 350. The slabs are monolithic along the upper chords of the main beams with concrete grade 400. For joint work, the main beams are combined with reinforced concrete slabs by means of stops. The stops are made of sheet steel.

Elevated sidewalks are arranged along sidewalk blocks. Fastening of sidewalk blocks is carried out by the protrusions in the prefabricated slabs and by the edges of the cantilevers of the roadway slab.

The main sequence for dismantling the bridge, proposed at the "P" stage, was as follows (Fig. 5):

- The superstructure in span 1-2 is dismantled by the railway. crane in the "window" of the movement of railway transport, spans 4-5 and 5-6 are dismantled using a truck crane with a lifting capacity of 100 tons or more, in spans 2-3 and 3-4 by a floating crane. Dismantling of outdoor lighting poles, barrier and railings and sidewalk consoles, starting from the middle of the spans to the poles using a crane with hauling by road;

- Removal of the asphalt concrete pavement of the roadway, starting from the middle of the spans to the supports;

- Dismantling of the protective layer and waterproofing, starting from the middle of the spans to the supports;

- Dismantling of sections of the roadway slab in the summer with a crane, with sawing them in a size of 3 * 3 m, followed by laying a wooden flooring from a bar for the movement of equipment. Dismantling is carried out simultaneously in spans 2-3, 3-4, 4-5 from the middle of the span to supports 3, 4 and 5.

- Installation of temporary supports in spans 1-2 and 5-6;

- Dismantling the rest of the roadway slab. Dismantling of the beams is carried out simultaneously with the dismantling of the superstructure blocks.

- Installation of temporary supporting supports at supports 3 and 4. Balanced dismantling with an MDK 63-1100 crane afloat, starting with the opening of the lock section in span 3-4.

- Dismantling of span 1-2 is carried out with the EBC-1000 crane, with the installation of a temporary support, in the "windows" with the relocation of the crane along different paths. The end block is dismantled by a truck crane from the approach.

The main reasons for rejecting the proposed option for dismantling the bridge spans at the "P" stage were:

- poor study of the design institute of the method of production of work, the absence at stage "P" and the failure to provide further calculations confirming the correctness of the decision;

- at stage "P" the general stress-strain state of the bridge superstructure was not taken into account;

- the use of floating cranes during the dismantling of the superstructure, which is difficult with the intensity of vessel traffic within the seaport water area;

- dismantling the span of 1–2 railway d. crane with a significant workload of the main course of the Moscow - Rostov - on - Don - Adler direction, as well as the absence at stage "P" of costs for reorganizing Russian Railways communications when operating with an EBC - 1000 crane.

Fig 5. General sequence of dismantling the bridge crossing at stage "P".

The basic scheme for dismantling superstructures at stage "P" is as follows (Fig. 6):

- disassembly in spans 4-6 is carried out by a self-propelled jib crane with the installation of temporary supports to support the superstructure in the cutting zones. Temporary supports on a natural foundation are made of inventory structures MIK - S and MIK - P.

- disassembly in spans 2-4 is carried out from the lock section in span 3-4 (middle of span 147 m) in both directions to supports 2 and 4 with UMK-2 cranes installed and moving along the rolling tracks on the haunches of the upper chords of the span beams along the beams 1 and 4. The dismantled structures are lowered onto the floating system and moved to the berth for unloading.

- disassembly in span 1-2 is performed by two cranes, from the lock section towards support 2 with a DEK 321 crane installed on the site in the area of ​​support 2 and from the lock section towards support number 1 with a Liebherr LTM1100 boom truck mounted on the carriageway of the superstructure. To dismantle span 1-2, temporary supports are installed from the MIK-S and MIK-P structures in spans 1-2 and 2-3. The extreme block to support 1 is dismantled by a truck crane from the approach.

Dismantling at all stages is carried out on one beam in the following sequence, first, two extreme beams are dismantled alternately, then two middle ones. The sequence of dismantling the extreme and middle beams is assigned in the PPR from the convenience of working with a crane and a floating system.

Preliminarily, on the length of the block, work is carried out to dismantle the longitudinal and transverse ties, the installation of a temporary railing along the upper chords of all beams, the suspension of all sets of rigging and scaffolding for the production of the cut.

Fig 6. The accepted scheme for dismantling the bridge crossing at the stage "P".

To make the final decision on the dismantling of the bridge spans and analysis of the state of the span structures, at each stage of dismantling, CJSC Scientific and Design Institute IMIDIS, under an agreement with OJSC Giprotransmost, monitored the stress-strain state of structures.

The main stages of work:

- determination of the initial stress in steel structures of steel beams;

- carrying out static tests;

- installation of a monitoring system and removal of zero reports;

- monitoring with data recording into the database.

The monitoring report was available on a continuous basis via the Internet through the KIS-control program “IMIDIS”.

In the course of the work, on a daily basis, the engineer of the RTF "MO-10" transferred to the design institute the scheme for carrying out work on dismantling the elements of the bridge crossing. The design institute compared the monitoring readings and the results during the work process, on the basis of which adjustments were made to the scheme for dismantling the roadway slab and haunches, i.e. correction of the constant load located on the superstructure at the stages of the beginning of the dismantling of the m.c. superstructure and subsequent stages.

Dismantling of the carriageway and bridge bed, in general, does not differ from the "P" stage. At the first stage, the asphalt concrete pavement is dismantled at a distance of 20 meters in the middle of the spans, then the barrier fence is dismantled along the entire length of the bridge. Next, the rest of the asphalt concrete pavement is cut off with a cutter weighing no more than 35 tons in strips of 2 m and the protective layer, waterproofing, leveling layer is disassembled in strips of 2 m with a span lagging behind the cutter (Fig. 7).

Fig 7. Dismantling of the carriageway and bridge bed at the "P" stage.

Dismantling of sidewalk blocks was carried out from the middle of span 3-4 in both directions from the upstream and downstream sides simultaneously. Dismantling in the navigable aisle was carried out during breaks in the movement of vessels, through communication with the port dispatcher, and in aisle 1-2 in a blind "window" with the removal of voltage in the contact network. In view of the emergency state of the supporting consoles of the roadway slab, on which the sidewalk block is installed with one edge, scaffolds were made of individual metal and IPRS elements for safety reasons for the period of work execution (Fig. 8).

Fig 8. Dismantling of sidewalk blocks. SVSiU for dismantling sidewalk blocks.

The sequence of dismantling was as follows: supporting scaffolds were brought under the blocks to be dismantled, then the block was connected to the supporting consoles, only after that the guardrail was dismantled throughout the dismantled block, the slinging holes were installed, the block was slinged, the block was cut from the mortgage, the block was dismantled with a crane with loading on a dump truck and installation of temporary railings. Further, by analogy, the movement of the scaffold, etc.

Dismantling of the roadway slab and haunches was carried out in accordance with the sequence developed by JSC "Giprotransmost", this sequence, first of all, took into account the stress-strain state of the bridge deck structures, as well as the adopted technology for dismantling the spans (Fig. 9).

Fig 9. Dismantling the roadway slab. Longitudinal cutting of a slab section with a HILTI hydraulic wall saw.

To carry out the work on cutting and dismantling the slabs, supporting structures were manufactured and applied in parallel, installed on the upper part of the slab.

The sequence of work for dismantling the plates is as follows:

- drilling holes for the installation of supporting structures;

- installation of supporting structures;

- cutting the slab along the haunch with circular saws, from seam to seam of the precast monolithic slab 2.62 m; - dismantling the slab with a crane; - the device of the flooring instead of the dismantled slab. The work was carried out simultaneously at several points and spans.

Dismantling of the hats was carried out with jackhammers, non-explosive mixture of HPC, concrete breakers, etc.

Taking into account the least complexity and the smallest amount of preparatory work in comparison with channel spans and span 1-2, as well as the decision to change the method of mounting the steel structures of the superstructure by means of conveyor-rear assembly and sliding from support No. 6, first of all, the floodplain spans were dismantled 5- 6 and 4-5. Dismantling was carried out by a crawler crane Liebherr LR 1130 with a lifting capacity of 130 tons. Dismantling was carried out on the same plane of the beams with hawks and with demountable haunches. Preparatory work included the dismantling of the longitudinal and transverse ties, the installation of slinging devices and the temporary loosening of the beams. During dismantling, special attention had to be paid to the release of the fourth beam in the order of dismantling. The dismantling of the third and fourth in the order of dismantling of the beams was planned with the least interruption and constant monitoring of the wind control according to the forecast and directly with an anemometer in place.

The span section 4-5 from support 4 to the temporary support BO1 was dismantled last, since its dismantling was linked to the dismantling of span 3-4 by a UMK crane, the span was a surcharge for part of span 3-4, and was also used for parking (when dismantling the last block), moving and dismantling the UMK crane.

Dismantling of the channel spans was carried out using a UMK-2 crane installed on the haunts of the upper chord of the outer beams of the superstructure. The crane stands were chosen mainly on the basis of the weight of the element to be dismantled and the vertical stiffener of the superstructure for fastening the crane. Before the start of work on dismantling the central block in span 3-4, work was carried out on the installation of two temporary supports, in span 2-3 on driven pipes on piles and two temporary supports in span 4-5 on a natural foundation. Temporary supports are made of bridge inventory structures MiK - S and MiK - P. In span 2-3, temporary supports are interconnected by a spacer in the upper level and with support No. 3 at the level of the spacer of support No. 3.

Before the start of work on cutting the lock section in span 3-4, work was performed at all previous stages, in accordance with the general sequence of work:

- disassembly of the roadway and sidewalk blocks;

- sub-linking of temporary supports in spans 2-3 and 3-4;

Dismantling at a distance of 75 m. Roadway slabs in span 3-4;

- dismantling of hats in span 3-4 at a section of 40 m in span 3-4;

- installation of two cranes UMK - 2 and their installation above supports 3 and 4;

- wedge of the movable support part on the support 3.

Immediately before the work was completed:

- installation of a frame with lifting cradles for cutting the section;

- dismantling of longitudinal and transverse ties at the cut site;

- the marking of the sequence of cuts has been made.

Facade lifts were purchased to carry out works on cutting the span structures. The main criterion for choosing front elevators is the significantly changing height of the vertical wall of the beams from 2.5 to 7 meters. Four front elevators mounted on a common frame moved along the rolling tracks of the UMK crane (Fig. 10).

Fig 10. Cutting the superstructure using front elevators.

Cutting of the span section of the interlocking section was carried out simultaneously along all four beams in accordance with the diagram issued by the design institute. According to the calculations of the designers, the superstructure should, after opening, remain close to the existing position or move upwards by an insignificant amount, which was confirmed by the monitoring data of the IMIDIS Institute.

After cutting the lock section, the central blocks of span 3-4 were dismantled with two UMK cranes during the breaks of vessel traffic. One crane carried out dismantling in the direction of support No. 3 and further to support No. 2, the other in the direction of support No. 4. To reduce the duration of the "windows", a significant amount of preparatory work was carried out:

- installation and release of UMK cranes; - dismantling of longitudinal and transverse ties; - installation or moving of a frame with front elevators;

- installation of scaffolds for slinging on all beams;

- rigging installation on all beams;

- installation of safety pads and cutting of the superstructure beams.

In the process of carrying out the "windows", the beams were directly slinged, the safety linings were dismantled and the dismantled beam was lowered onto the barge.

Equipment used for cutting: a high-strength cutter of the NORD-S type and an UVPR2001 air-plasma cutting unit with PRV 301 and VPR 405 plasmatrons.

The cutting sequence proposed by the institute is as follows: creating longitudinal cuts with a pitch of 100 mm at a distance of 400 mm from bottom to top, then cutting across the joint from bottom to top with opening along the upper chord.

Before the start and during the production of work, changes were made in the order of the cut due to the technology, the placement of the scaffolds on one side (window cutout) and a decrease in the volume of striping of the vertical wall in the zone of zero moments (window cutout along the vertical wall). Cross-cut device with a strip 5-7 cm wide and final opening at the bottom of the wall (Fig. 11).

Rice. 11. The final section of the lock cut.

Figure 12. Dismantling of the central "locking" blocks by derrick cranes UMK-2 in the channel span 3-4

In the course of making a decision on the method of disassembling span 1-2, various options were considered (use of an EBC 1000, KShK crane, installation of a jib crane with a lifting capacity of 130-200 tons at support 2, etc.). The implemented version provides for the dismantling of beams with two cranes from the lock section in different directions (Fig. 13, Fig. 14). The main stages of the work were as follows:

- installation of three temporary supports;

- jacking up the superstructure on a temporary support 2, creating the necessary effort;

- installation of counterweights over the temporary support 3

; - opening of the locking section in span 1-2; - dismantling of beams with the performance of work by analogy with spans 2-4.

The main difficulty in performing the work was the possibility of providing "windows" in the movement of the railway. transport, duration from 45 to 90 minutes, including the work of ECHK and PCh.

The cutting of the locking section was carried out by analogy with span 3-4, with the exception of a change in the design of the scaffold associated with the presence of a railway. and the order of cut associated with the predicted downward movement of the superstructure.

Fig 13. Dismantling of the superstructure of the bridge crossing in span 1-2 with a DEK-321 crane, in the railway right-of-way.

Fig 14. Dismantling of the superstructure of the bridge crossing in span 1-2 with a LIEBHERR LTM-1100 crane.

The development and execution of works on dismantling the bridge crossing using various methods of work with maximum accuracy, in a short time, near the existing bridge crossing became possible thanks to the well-coordinated work of engineers, workers of RTF "Mostootryad-10", as well as specialists of JSC "Giprotransmost", institute "IMIDIS".

Grinding, lifting and transporting pieces of concrete construction.

The technique dismantles buildings in three ways:

• Classic demolition and dismantling of monolithic reinforced concrete. Concrete buildings are destroyed by ball hits, and.
• Preliminary destruction, crushing of concrete and dismantling of reinforced concrete floors and walls.
• Dismantling of reinforced concrete, dismantling and removal of elements, dismantling of equipment. Concrete buildings often contain many products that can be reused or recycled.

After dismantling, concrete chips are possible, destruction and dismantling of reinforced concrete structures of the underground part of the building, landscape restoration, preparation of the territory for new construction.

Price demolition and dismantling of reinforced concrete structures and reinforced concrete objects

Type of work
Dismantling of reinforced concrete structures
Dismantling of reinforced concrete fencing
Dismantling of concrete blocks
Dismantling of reinforced concrete fence
Dismantling of reinforced concrete walls
Dismantling of reinforced concrete supports
Dismantling of concrete, reinforced concrete pipes
Dismantling of bridge structures
Dismantling the bridge
Monolithic concrete structures of increased strength (dense reinforcement) such as bridge supports, foundations of tower cranes

Dismantling of reinforced concrete structures: price and equipment for dismantling

Depending on the complexity and scale of the project, any equipment from the ProgressAvtoStroy vehicle fleet is used to dismantle reinforced concrete and concrete structures. We offer special equipment, teams that perform manual dismantling and dismantling of structures, machines for waste removal, earthmoving equipment for demolition and site restoration.

Dismantling of reinforced concrete supports, pillars and concrete structures with a dragline with a ball ("woman")

The impacts of a load weighing up to three tons make it possible to dismantle tall reinforced concrete structures, knock down pillars and pillars, and destroy walls and floors of concrete buildings. Such dismantling is suitable when there is no powerful metal frame inside the concrete building, and around there is enough free space for debris to fall and the possibility of the site allows the use of special dismantling equipment.

Hand held power tool for demolishing concrete buildings

For manual dismantling of reinforced concrete structures, the price is usually higher than when using technology, but the dismantling of reinforced concrete products helps to do without dangerous large-scale destruction. Plasma cutters and grinders prepare concrete structures for subsequent demolition, installers act - they carry out dismantling work, cut reinforcement, separate the bearing parts that interfere with the operation of machines.

Dismantling with a tool based on special equipment (hydraulic shears, hydraulic hammer)

Powerful dismantling tools quickly break and grind pieces of the structure. The equipment is suitable for dismantling at a height, performing services for the dismantling of reinforced concrete structures of any type. Often, hydraulic breakers, hydraulic shears and buckets are used to destroy concrete and brick walls, to open the base of a structure - this facilitates the demolition and dismantling of the metal frame, the reinforced concrete structure is easily folded.

Grapples, grippers, cranes and attachments: dismantling and loading concrete

The equipment is used to assist in the dismantling, disassembly and loading of fragments of reinforced concrete structures. The equipment completes the dismantling process: it lifts the reinforced concrete and large pieces of the building, takes them out of the dismantling area, and moves them to the loading or waste collection area.

Bulldozer or front loader: dismantling and waste collection

The machine is independently engaged in dismantling small buildings (for example, the demolition of reinforced concrete garages in Moscow is usually carried out by bulldozers), and on large-scale projects it is used for loading, leveling the territory. Sometimes the technique is used as a tractor, which tears off or helps to dump concrete structural elements - such dismantling is faster and safer than other methods.

Excavators: demolition and demolition of concrete

The dismantling of reinforced concrete structures is inexpensively performed - the price per cube is calculated with the subsequent loading of concrete. Excavators help to completely demolish the building, including the dismantling and loading of parts of underground utilities.

Dismantling of reinforced concrete structures: prices and order

Contact a representative of ProgressAvtoStroy and specify how much it will cost to dismantle reinforced concrete: supports, pillars, slabs and concrete structures in your case (see also the section). Get complete information: prices for objects (Moscow, Moscow region), deadlines for dismantling, removal of reinforced concrete. When concluding a contract, an engineer comes to the facility, draws up a concrete dismantling scheme and calculates the final cost.

Working documentation can be downloaded in pdf format (scan)

The history of the construction of the overpass

The project of organizing work on the demolition and dismantling of capital construction objects (overpass) The overpass is single-span, double-track under I, 11 main tracks. The design scheme is 1x5.0 m, the total length of the overpass is 7.73 m, the opening is 4.0 m. The distance between the cabinet walls is 5.73 m.

The overpass was built in 1861 during the construction of the Moscow-Petushki line through Obiralovsky proezd in the village of Kuchino, for the passage of transport.

In 1976, the bridge was overhauled with the replacement of superstructures, according to the project No.ZHDP-7352, carried out by the Zheldorproekt Institute in 1973.

In 2002, in the immediate vicinity of the overpass, in the body of the railway embankment from the Petushki side, two road tunnels were built for the passage of vehicles.

At the moment, under the overpass, the passage for vehicles is closed, pedestrian passage is taking place.

Overpass design

Reinforced concrete overpass, single-span, double-track.

Spans - reinforced concrete, slab, two-block, design span - 5.0 m, full length - 5.6 m. No. 557, designed for C-14 load, installed in 1976, the volume of reinforced concrete of each superstructure - 10.25 m3

Support parts - metal, welded, flat, grade P-1 are made according to the standard design inv.No.557

Massive stone abutments were built in 1861. Abutments length - 2.86 m. Width - 10.73 m, abutment masonry volume with foundations = 369.87 m3 Abutments are plastered.

During the overhaul of the overpass in 1976, the cabinet walls of the abutments and cordon blocks were partially dismantled, new cordon blocks were installed on the side of the second track.

Rubble concrete wings are attached to the abutments, located at an angle to the abutments, on the right side along the course of kilometers, the wings are lengthened by FBS blocks, on the left side they are conjugated with concrete retaining walls of the abutments of the III track bridge.

Shallow foundation on a natural foundation. The depth of the foundation is 2.13 m.

The path on the overpass and approaches is continuous on reinforced concrete sleepers. Rails R-65. Crushed stone ballast.

Before starting work, it is necessary to carry out the following organizational and technical measures:

Comprehensively survey structures in order to clarify the future scope of work, identify dangerous places and determine measures to ensure the safety of people. Based on the results of the survey, an act is drawn up on the basis of which the decisions of the following issues are determined (the choice of the method of disassembly, the establishment of the sequence of work, dust suppression measures, etc.);

Decide on the order, stages, demolition queues:

Disable existing communications: electricity;

Enclose the work area (construction site) with a security mesh fence;

Prohibit the admission of unauthorized persons to the site;

Prevent the entry of strangers and animals into the object;

Carry out the removal of green spaces according to the inventory lists;

The overpass dismantling project proposes to dismantle all structures by dismantling;

Complex auxiliary structures and devices.

Dismantling of the overpass is being carried out in the conditions of the existing railway. This section is used by high-speed rolling stock.

To ensure safe traffic during the work, the project provides for the dismantling of the Obiralovsky overpass under the unloading packages along all three tracks.

The unloading package with an estimated length of 18.2 m with a ride on top on wooden crossbars was made according to the standard project 2176/2000.

Due to the fact that high-speed trains circulate on the site, the project provides for the installation of a pile foundation for temporary stacked superstructures made of metal pipes with a diameter of 630 mm and a wall thickness of 8 mm.

Security devices are represented by counter-drills and security corners. Pedestrian walkways on metal consoles with wooden plank flooring are arranged on both sides of the superstructure. For the possibility of placing the superstructure on abutments No. 0 "and No. G, on one side the sidewalk consoles are shortened and there is no handrail. The sidewalk guardrail consists of metal posts and handrails, filled with round bars. The elements of the superstructure are made of steel grades 15ХСНД or 10ХСНД. Elements of sidewalks, railings, diaphragms of the main beams made of steel grade 16D. Support of the superstructure on abutments VU1, VU2 through movable support parts of the T2PL type according to N 2120RCH, developed by JSC "Transmost". The position of the supporting parts on the grillage of the temporary abutment is fixed with stops. On the abutments No. 0 "and No. G, the superstructure rests on fixed support parts of the T2N type according to the project No. 2120RCH, developed by JSC" Transmost ". In the lower chord and the supporting sheet of the superstructure, holes ø25mm are made for fastening the supporting parts with bolts.

The abutments for the 3rd track are without grillage, on a pile foundation of 2 piles. Piles from a pipe ф630х8, length 7.4 m, steel ВСт20. Bollards for supporting superstructures made of I-beams No. 55B1

The abutments for the 1st and 2nd tracks are without grouting, on a pile foundation of 4 piles. Piles from a pipe ф630х8, length 7.4 m, steel ВСт20.

Temporary spans rest on a transverse girder, which in turn rests on piles at the edges, and in the intertrack on a longitudinal girder made of I-beams No. 55B

Organization of the construction site

For the arrival of construction equipment, technological drives are arranged on both sides of the overpass through the 1st Nth track. For the arrival of the technician in the inter-track, technological platforms are arranged through the railway tracks, which are used only during the "window".

Two technological platforms for the operation of an excavator with attachments are arranged between the paths. The excavator must be parked between the paths in strict observance of the dimensions of the approach of the structure along the adjacent tracks.

To service the staff, a platform with change houses, toilets and a foreman's room is being arranged.

Technological sequence of work

Work on the construction of temporary bridges is carried out in the "windows", according to the schedule of their provision, developed in the PPR.

All work on the construction of temporary bridges is divided into two stages:

... Stage I. Construction of the pile foundations of temporary bridges.

The temporary batch superstructure (SPB) for track III rests on a pile foundation in the amount of 2 pcs. from each side. Piles are met. a pipe 630 mm in diameter and a wall thickness of 8 mm and a length of 10 m. Prior to the start of the main "window", the piles are transported to the work area by an automatic machine with ADM-4 and unloaded into the pathway observing the size of the building approach.

After the start of the "window", the pile is vibrated to the design level by an excavator with attachments, a vibratory pile driver with a side grip Movax SP-40F. At the time of work on the site, the contact network is not dismantled.

In this way, a pile foundation is made for the temporary superstructure of the 3rd track. During the operation of the excavator, the clearance along the adjacent tracks is not violated.

A similar technological sequence for the construction of the pile foundation and for temporary package superstructures of the 1st and 2nd tracks.

... Stage II. Installation of superstructure supports and temporary stacked superstructures.

Before the start of work in the main "window", transportation to the place of work, unloading and laying out at the site of technological equipment, structures of support heads, longitudinal and transverse girders is carried out. As well as cutting continuous welts in the work area on inventory rails of 3x12.5 m on each track and joining them into rail joints.

In the main "window" with the closure of the traffic on the Sh-th track by the track-laying crane UK-25SP, the upper structure of the track is dismantled with the loading of the links onto the cover platform. After dismantling the first link, the excavator begins to dismantle the soil to the design level for cutting pipe piles, installing their heads and supporting beams.

After dismantling the track superstructure, the track-laying crane is retracted to a safe distance of 50 m. After that, a team of workers begins to cut the ballast trough.

In parallel with these works, the construction of the pile foundation is being carried out on the opposite side.

After cutting the ballast trough, a track-laying crane is brought in and the existing superstructure of the 3rd track is torn off and dismantled with loading onto the covering platform.

After dismantling the existing superstructure of the 3rd track, the tracklayer is retracted to a safe distance, the platform is uncoupled with the superstructure of the track and the existing superstructure. Then the platform is transported to the place of unloading at the base of the local FC or PMS.

After that, the second set is fed to the crane by a cover platform with a submerged temporary package superstructure and a bridge deck.

In parallel with these works, the construction of the pile foundation and the installation of the support girder continue, as well as the cutting of the top of the cabinet wall by a backhoe loader with hydraulic hammer attachments to the design level. The crossbar is mounted by the excavator boom from the path to the design position.

After finishing works on construction and cutting of concrete at the top of the cabinet wall, a track-laying crane is brought in, which mounts a temporary package superstructure on the axis of the track.

At the final stage, the sinuses are backfilled with crushed stone, the installation of the bridge deck, security devices, and the restoration of the contact network

Installation of temporary bridges under the I-th and N-th tracks is carried out in the "window" to be carried out with the closure of traffic on both tracks. The dimension along the Sh-th path is not violated.

The rest of the work is carried out in the same sequence.

The structures must be as strong and reliable as possible, therefore, after the end of the operational period, they undergo reconstruction or dismantling, depending on the degree of wear. Otherwise, it is fraught with car accidents, accidents, accidents. Violations of integrity are influenced by many factors - the geo-meteorological impact of nature (precipitation, seismic activity, ground movements), the degree of traffic intensity of heavy vehicles.

The company carries out a complex of dismantling works for the demolition of bridges, flyovers and overpasses in Moscow and the region. We use our own special machinery and equipment, due to which the total cost of work is reduced. We cooperate with road construction companies, large contractors.

Demolition methods

There are 3 types of work. Their choice is based on factors such as the size of the structure, the type of construction, the material of the road surface. An important role in the work is played by the physical condition and features of deformation, the presence of paths for a detour. The conditions of movement of transport are also taken into account - whether the structure is partially used or completely blocked. A prerequisite is the provision of a bypass route.

1. Explosive - the technique is used only in cases where there are no conditions for harm to people and the environment. For example, if a structure is located in the very center of the city, then it is forbidden to blow it up. The explosive method is used for monolithic bridge structures.
2. Manual - the method involves manual disassembly. This is possible only with prefabricated types of structures. Each element is parsed in segments. For this, various tools, laser cutting and other specialized equipment are used.
3. Mechanized - special equipment is used (rigging and jacking system, cranes, barge platforms).

The specifics of work on various types of structures

Depending on the type, different methods of dismantling and special equipment are used. Steel structures are dismantled piece by piece. For this, cranes, hydraulic jacks and similar equipment are used, scaffolds and additional supports are installed. Initially, specialists check the points of perception of loads, after which the secondary elements are removed.

Reinforced concrete structures are destroyed by means of a jib crane. If they are small and located above the river, then the cranes move along the locomotive, for which a rail system is pre-installed from 2 banks. If the structure runs across a wide river or has many spans, a barge or cross-movement is used. It is imperative that lifting beams, collapsible towers, hydraulic jacks are installed under the span to be dismantled. The concrete foundation is neutralized with demolition excavators, hydraulic shears and hammers.

The wooden assembly is dismantled by a collapsible method or by means of rope winches. If you need to remove a temporary building, it is easy to disassemble, since it is initially made in such a way that it can be easily disassembled and reassembled.

Structures that pass through water bodies deserve special attention, because here specialists are required to comply with additional requirements. First of all, the penetration of construction debris into the water is excluded. For this, diamond cutting is used, which is recommended for the demolition of reinforced concrete, concrete and monolithic structures. The connecting elements are disassembled in the opposite way. The data is indicated in the project for the device of the bridge. The order in which the fasteners are removed must be followed. When disassembling elements containing a concrete mixture and if there is a railway or river track under the bridge, it is necessary to block the movement of vehicles. In this case, the rails and sleepers are covered with protective boxes.

In order to order a service from us, call the managers of the company at the indicated phone numbers or leave a request on the website. We can calculate the cost of dismantling in advance, prepare all the documentation and answer your questions. And our specialists will fulfill the order with high quality.