The invention relates to bridge construction, namely to a method and device for dismantling bridges.

The patent for the invention of the Russian Federation No. 2250285, IPC E01D 22/00 is known. “Method of replacing a bridge superstructure.” A method for replacing a bridge superstructure, including installing the existing superstructure to be dismantled on floating supports, followed by dismantling the superstructure using at least one load-lifting movable crane, loading the disassembled elements of the superstructure onto floating facilities and delivering them to the shore, and erecting a new bridge superstructure , characterized in that when dismantling an existing metal end-to-end span structure with belts, braces, racks, hangers and gussets, before installing the span to be dismantled on floating supports in the alignment of the span's support nodes, temporary piers are erected and the span to be dismantled with support is moved transversely it onto temporary piers, after which a new span is erected along the longitudinal axis of the bridge and a load-lifting movable crane is installed on it, and two floating supports are placed under the span to be dismantled, which are located at one of the ends of this span, and the dismantling of the span is carried out with one end of the span to the other with the initial transfer of the load from the span from one of the piers to both floating supports, and as the elements of the span are dismantled, each floating support located on the side of the dismantled section, after dismantling this section, is moved along the dismantled span and installed behind the second floating support, while the dismantling of the elements of the superstructure is carried out using a load-lifting crane, which is moved along the erected new superstructure as the dismantling section moves, and the dismantling of sections of the existing superstructure is carried out from top to bottom by initially cutting out the linear elements of the upper chord, then the racks, pendants , braces, and then elements of the lower chord, while the gussets are cut out separately or together with the posts and pendants. When supporting the span to be dismantled on floating supports, each floating support is anchored. Before cutting out any element of the dismantled span, this element is slung to the crane hook with slings in a loose state. Work on cutting the span is carried out from suspended scaffolding. When replacing the superstructure of a double-track bridge, work on replacing the superstructure for the second track is carried out similarly to work on replacing the superstructure under the first track.

The disadvantage of this method is that it is quite labor-intensive, requires the construction of additional structures and the involvement of additional equipment, and during the proposed dismantling of the bridge it is necessary long time occupy the space under the bridge (water area).

The closest (prototype) to the claimed invention is the patent for the invention of the Russian Federation No. 2304656, IPC E01D 22/00, “Method for dismantling with volumetric blocks a lattice superstructure of a bridge.” A method for dismantling in volumetric blocks a lattice superstructure of a bridge with a height of the upper chord above the water level of up to 30-35 m and with a span of more than 40 m, including the construction of temporary auxiliary supports in places where the trusses of the span structure are divided into volumetric blocks, the installation of hydraulic jacks on temporary auxiliary supports under lower nodes trusses, temporary fixation of them, at least for the period of division, from vertical movement by wedging with steel sheets on capital or auxiliary supports, dismantling of the roadway in the area of ​​volumetric blocks, division of the span into volumetric blocks of at least 20 m in length by cutting or cutting individual elements of the truss while ensuring the regulation of internal forces in the truss by means of a wedge and/or using hydraulic jacks installed on auxiliary supports within the limits of static loads acting in the elements of the truss that do not exceed the design loads, slinging, release from temporary fixation and dismantling of isolated blocks by a floating crane with a lifting capacity of not less than 80 tons with their movement to pre-prepared receiving stocks for their disaggregation on the shore and dismantling of temporary auxiliary supports. The division of the truss is carried out initially along the upper, then along the lower chords, starting from the top plane of the truss. Receiving slips are placed on the shore, and the separated blocks are moved onto them by a floating crane immediately after their dismantling, excluding transfer to a barge or dinghy. Receiving slips are placed on the shore, and the separated blocks are moved onto them by a floating crane after they are transferred to a barge or dinghy.

The disadvantages of this method are the complexity of additional work performed, the involvement large quantity equipment and long periods of work directly under the span, which prevents the use of the under-bridge space (water area).

The objective of the proposed invention is the fastest possible removal of the span from its location and the possibility of dismantling the span on the shore.

The task is solved by installing hydraulic jacks under the lower chord for jacking, after which channels are installed under the lower chord of the beams, then a metal traverse is installed, after that the traverse is combined with the channels, then a pylon is built on the traverse, then the cables are suspended and tensioned, after that the supporting parts of the beams are replaced with a movable device, after whereupon the span structure, together with the formed prefabricated structure, is pulled out onto receiving slipways located on the shore, and the span structure is dismantled. Channels under the lower chord of the beams are installed in the longitudinal direction. The traverse is installed along the entire span of the bridge to be dismantled. The traverse and channels are combined by means of vertical rods followed by welding to each other. A pylon is built, for example, in the middle of a span. Rollers or fluoroplastic pads are used as a moving device.

The essence of the claimed invention is illustrated by drawings.

Figure 1 shows a fragment of the existing beam reinforced concrete bridge superstructure.

Figure 2 shows a fragment of the connection of channels installed under the lower chord of beams with a crossbeam.

Figure 3 shows the bridge span with installed channels and a traverse along the entire span.

Figure 4 shows the bridge span with an installed pylon, channels and traverse, tensioned cables and a movable device installed instead of the supporting parts of the beams.

Figure 5 shows a bridge superstructure shifted by some distance with an installed pylon, channels and traverse, tensioned cables and a movable device installed instead of the supporting parts of the beams.

The method of dismantling the beam reinforced concrete bridge superstructure 1 using a cable-stayed system 2 consists of the following operations: install hydraulic jacks (not shown) under the lower chord 3 of beams 4, then jack up the superstructure 1, after which channels 5 are installed under the lower chord 3 of beams 4, then a metal traverse 6 is installed, after which the traverse 6 is combined with the channels 5, then a pylon 7 is built on the traverse 6, then the cables 8 are suspended and tensioned, after which the supporting parts 9 (for example, blocks) of the beams 4 are replaced with a movable device 10, after which pull out the span 1 together with the prefabricated structure 11 formed from beams 4, channels 5 and traverse 6 onto receiving slipways 12 located on the shore 13, and dismantle the span 1 (see Figs. 1, 2, 3, 4, 5) .

The channels 5 under the lower chord 3 of the beams 4 are installed in the longitudinal direction (see Fig. 2).

The traverse 6 is installed along the entire span 1 of the bridge to be dismantled. The crossbar 6 and the channels 5 are combined by means of vertical rods 14, followed by welding to each other (see Fig. 2, 3, 4, 5).

The pylon 7 is constructed, for example, in the middle of the span 1 (see Figs. 4, 5).

As a movable device 10, rollers 15 or fluoroplastic pads 16 are used (see Figs. 4, 5).

As a result of the proposed work, the span can be dismantled without the use of lifting equipment and the construction of additional structures.

The use of a cable-stayed system and a prefabricated structure makes it possible to balance the span in such a way that it will not crack, deform, or be subject to skew or shift while pulling the span onto the receiving slipways.

The problem is solved due to the proposed sequence and combination of works in the proposed method, namely:

1. Jack up the span 1 with hydraulic jacks installed under the lower chord of the beams (not shown).

2. Install channels 5 with a tight fit to beam 4.

3. Install a metal crossbeam 6 to strengthen the long structure of the span 1.

4. The traverse 6 is combined with the channels 5 by means of a tie with vertical rods 14 and the use of welding.

5. A pylon 7 is installed on a reinforced prefabricated structure 11, consisting of beams 4, tightened by a traverse 6 and channels 5.

6. The cables 8 are suspended, after which they are tensioned, thereby strengthening the prefabricated structure 11.

7. Replace the supporting parts 9, for example blocks, with a movable device 10, for example rollers 15 or fluoroplastic gaskets 16.

8. The span 1 is pulled onto the receiving slipways 12 installed on the bank 13.

9. The span 1 is dismantled.

Industrial applicability lies in the fact that to implement the proposed method, well-known equipment is used, which is used in various fields and does not require additional manufacturing or modification.

All of the above indicates the solution to the problem, namely:

List of positions

1. Superstructure

2. Byte system

3. Bottom belt

5. Channel

6. Traverse

9. Support part

10. Mobile device

11. Prefabricated structure

12. Receiving slipways

14. Vertical thrust

16. PTFE gasket

1. A method for dismantling a beam reinforced concrete bridge span using a cable-stayed system, including installing hydraulic jacks under the lower chord for jacking and placing receiving slipways on the shore, characterized in that after installing the hydraulic jacks and jacking, channels are installed under the lower chord of the beams, then installed a metal traverse, after which the traverse is combined with the channels, then a pylon is built on the traverse, then the cables are suspended and tensioned, after that the supporting parts of the beams are replaced with a movable device, after which the span along with the formed prefabricated structure is pulled out onto the stocks and the span is dismantled.

2. The method according to claim 1, characterized in that the channels under the lower chord of the beams are installed in the longitudinal direction.

3. The method according to claim 1, characterized in that the traverse is installed along the entire span of the bridge to be dismantled.

4. The method according to claim 1, characterized in that the traverse and channels are combined by means of vertical rods, followed by welding to each other.

5. The method according to claim 1, characterized in that the pylon is constructed, for example, in the middle of the span.

6. The method according to claim 1, characterized in that rollers are used as a moving device.

7. The method according to claim 1, characterized in that fluoroplastic gaskets are used as a movable device.

Similar patents:

The invention relates to the field of aerohydrodynamics of bluff structures and concerns the issue of transverse vibrations of bridge spans caused by wind influence, solves the problem of reducing vibrations of a bridge superstructure caused by wind while reducing material consumption.

The invention relates to bridge construction, namely to a method for dismantling a bridge superstructure using a cable-stayed system. The method for dismantling a bridge superstructure using a cable-stayed system includes: preliminary construction on the lower chord in the sidewalk area of ​​the superstructure of an H-shaped pylon similar to a self-erecting tower crane and exceeding the height of the superstructure, suspending the superstructure with cables and tightening the cables, dismantling part of the shore supports to the level span structure and installation of a foreback on one side of the span, and on the other side, installation of a rolling out device, then jacking up the span and installing it on rollers, after which rolling out the entire span ashore onto pre-prepared stocks and subsequent dismantling of the span. The invention allows dismantling without additional accessories, free the water area in the shortest possible time, dismantle the bridge on the shore in less time without involving additional equipment. 5 salary f-ly, 6 ill.

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The invention relates to bridge construction, namely to a method and device for dismantling bridges. The method of dismantling a beam reinforced concrete bridge superstructure using a cable-stayed system makes it possible to quickly remove the superstructure from its location and the possibility of dismantling the superstructure on the shore due to the fact that hydraulic jacks are installed under the lower chord for jacking, after which channels are installed under the lower chord of the beams, then a metal traverse is installed, after which the traverse is combined with the channels, then a pylon is built on the traverse, then the cables are suspended and tensioned, after that the supporting parts of the beams are replaced with a movable device, after which the span along with the formed prefabricated structure is pulled out onto receiving stocks placed on shore, and the span is being dismantled. Channels under the lower chord of the beams are installed in the longitudinal direction. The traverse is installed along the entire span of the bridge to be dismantled. The traverse and channels are combined by means of vertical rods followed by welding to each other. A pylon is built, for example, in the middle of a span. Rollers or fluoroplastic pads are used as a moving device. The invention makes it possible to increase the efficiency of dismantling due to the maximum quick removal of the span from its location and the possibility of its dismantling on the shore. 6 salary f-ly, 5 ill.

Supports require scheduled repairs in accordance with identified defects. Due to the difference in construction heights of old and new spans, it is necessary to reconstruct the underframes in order to maintain the level of the rail base at the same level, and to replace the supporting parts.

3.2. Characteristics of new spans.

Main spans (2-3, 3-4, 4-5)

Estimated length: 77.00m;

Panel length: 4x8.25+2x5.5+4x8.25m;

Number of panels: 10;

Truss height in the middle of the span: 11.25m;

Construction height in span: 1.57m;

Distance between truss axles: 5.7 m;

Metal consumption per 1 running meter structures: 2.96t;

Metal consumption for the entire span: 230.0t;

Total weight of the span: 323.4t;

Side spans (1-2, 5-6)

Estimated length: 11.50m;

Construction height in span: 1.85m;

Total weight of the span: 32.0t;

A diagram of the new main spans is shown in Fig. 3.

Fig.3. Diagram of the new main spans.

3.3. Technology for replacing spans 1-2, 5-6.

Replacement of the outer spans is carried out using the EDK-500 crane.

Work must be carried out through windows.

The span is assembled close to its installation site parallel to the railway track on the embankment of the approach to the bridge. The finished span is loaded by a full-rotating rail-mounted crane EDK-500 onto an empty railway platform and transported to the installation site along with the crane. Replacement of spans is also carried out using the EDK-500 crane.

The crane is brought into working position: outriggers are installed, counterweights are hung. The superstructure to be replaced is removed by a crane and installed on temporary supports outside the approach clearance of the buildings. After which the installation of a new span takes place.

Cleaning of the old span is carried out with the same crane, but in the next window.

Crane outriggers are installed on temporary embankments lined with cages made of timber or old sleepers.

From the Tuapse side, the new span is first installed along the axis of the assembly of new trusses, to carry out semi-mounted installation of lattice spans, using a crane on a railway track, i.e. installation of a temporary abutment along the dismantling axis is not required.

When removing the old span from the Armavir side, temporary supports designed for transverse movement and a temporary abutment are used.

The window work schedule for replacing the superstructure is given in Appendix 1.

3.4. Technology for replacing spans 2-3, 3-4, 4-5.

Replacement of the main spans is carried out using the transverse movement method.

Temporary supports are mounted at a distance of 12 m from the bridge axis on both sides.

This method has become most widespread in the practice of replacing superstructures of medium and large spans. The technology for replacing the span includes:

Assembly of a new bridge on an axis parallel to the axis of the existing bridge using the semi-hinged installation method;

Installation of knurling devices;

Arrangement of traction (pushing) and braking devices;

Transverse (across the axis of the bridge) rolling out of the superstructure being replaced along special piers located at the ends of the superstructure;

Transverse rolling of the new span into the place of the one being replaced with preliminary reconstruction of the under-truss support areas;

Installation of a new span on supporting parts with preliminary dismantling of knurling devices;

Cleaning of the old span;

Dismantling of technological equipment.

The new span is assembled using a semi-mounted method using an EDK-500 crane and a UMK-1 derrick crane.

The movement is carried out using special rolling devices along piers thrown between permanent and temporary supports. The design of the temporary support is presented on sheet 2 of the drawing set. Electric winches of large rope capacity are used as traction devices. Traction forces are created through chain hoists. Braking devices are similar to traction ones.

Transverse movement of the span is carried out at “windows” in the train schedule. The spans move across the bridge axis on special piers, similar in design to the temporary rolling supports used for longitudinal sliding. Transverse movement of the old and new span is carried out at a minimum speed (30-40 cm/min) using traction and rolling devices similar to those used for longitudinal sliding.

Upon completion of the movement, the new span is jacked up, the underframe is rebuilt and new supporting parts are installed.

The window work schedule for replacing the superstructure is given in Appendix 2.

3.5. Technology for dismantling old spans.

The replaced spans, 78.40 m long, are subject to cutting and scrapping.

It is economically feasible to dismantle the spans using the method of longitudinal displacement of the spans and subsequent disassembly on a temporary embankment.

For longitudinal displacement of the combined span structure l=3x77, it is necessary to install 6 additional temporary supports from MIK-S elements, two for each span.

Foundations:

A vertical crack approximately along the axis of the bridge with an opening of more than 0.5 mm runs along almost the entire height of the abutment. To eliminate the defect, it is necessary to install reinforced concrete belts that compress the body of the abutment, or to install a protective reinforced concrete jacket. For crimping, reinforcing bars or high-strength ropes are passed through the body of the abutment, which are subsequently crimped along the belts using anchor devices and jacks or nuts. The force can be controlled with a torque wrench or by pulling out the rods.

To prevent the development of small hairline cracks with an opening close to critical, the abutment body can be partially shotcreted with the preliminary installation of reinforcing mesh.

Channel supports:

The intermediate supports have defects in the form of deep cracks, masonry failure and leaching of the mortar.

To prevent the development of these defects, it is necessary to perform cementation of the masonry, which consists of injecting a water-cement solution into the masonry through wells drilled in the support, which will connect the separated parts of the massif into a single whole.

Wells with a diameter of 35 mm are drilled with a hammer drill. They are placed in a checkerboard pattern in the seams between the stones. Side wells are installed obliquely to the horizon on both sides of the support to a depth of no more than 3/8 of the support thickness.

Demolition of bridges of any type is one of the specializations of the Triumph construction company. We have everything necessary tolerances, workers and technical means for dismantling bridges of any complexity.

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How much does it cost to demolish a bridge?

The preliminary cost of bridge dismantling is calculated based on the following data:

Our specialist will tell you the exact cost of the work after visiting the site and carrying out all the necessary engineering calculations.

Dismantling technology

Work begins with an inspection of the facility, after which a decision is made on the use of certain technical means.

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Working documentation can be downloaded in pdf format (scanned)

History of the construction of the overpass

Project for organizing demolition and dismantling works capital construction(overpass) Single-span, double-track overpass under I, 11 main tracks. Design diagram - 1x5.0 m, total length of the overpass - 7.73 m, opening - 4.0 m. Distance between cabinet walls - 5.73 m.

The overpass was built in 1861 during the construction of the Moscow-Petushki line through Obiralovsky Passage in the village of Kuchino to allow traffic through.

In 1976, the bridge was overhauled with the replacement of spans, according to 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 on the Petushki side, two road tunnels were built for the passage of vehicles.

At the moment, the passage under the overpass is closed for vehicles, pedestrians are passing through.

Overpass design

The overpass is reinforced concrete, single-span, double-track.

Span structures - reinforced concrete, slab, two-block, design span - 5.0 m. total length - 5.6 m. made in relation to standard project inv. No. 557, designed for C-14 load, installed in 1976, the volume of reinforced concrete of each span is 10.25 m3

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

The massive stone foundations were built in 1861. The length of the abutments is 2.86 m. The width is 10.73 m, the volume of masonry of the abutments with foundations = 369.87 m3. The abutments are plastered.

At major renovation Overpass in 1976, the cabinet walls of the abutments and cordon blocks were partially dismantled, and new cordon blocks were installed on the side of track II.

Rubber concrete wings are attached to the abutments, located at an angle to the abutments; on the right side, along the kilometers, the wings are extended with FBS blocks; on the left side, they are connected to the concrete retaining walls of the abutments of the III track bridge.

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

The path on the overpass and continuous approaches 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 inspect 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 inspection, an act is drawn up on the basis of which solutions to the following issues are determined (choosing a disassembly method, establishing the sequence of work, dust suppression measures, etc.);

Decide on the order, stages, and queues of demolition:

Disable existing communications: electricity;

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

Tolerance unauthorized persons prohibited from entering the site;

Do not allow unauthorized people and animals to enter the facility;

Carry out the removal of green spaces according to the accounting statements;

The project for dismantling the overpass proposes to dismantle all structures by disassembling;

Complex auxiliary structures and devices.

Work to dismantle the overpass is carried out under the current conditions railway. High-speed rolling stock operates on this section.

To ensure safe traffic during the work, the project provides for the dismantling of the Obiralovsky overpass under 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 is made according to standard design 2176/2000.

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

Security devices are represented by counter-angles and security corners. Pedestrian sidewalks on metal cantilevers with wooden plank flooring are installed on both sides of the span. To make it possible to place the span on abutments No. 0" and No. G on one side, the sidewalk consoles are shortened and there is no railing. The sidewalk railing consists of metal posts and handrails, the filling is made of round bars. The elements of the span are made of steel grades 15HSND or 10HSND . Elements of sidewalks, railings, diaphragms of the main beams made of steel grade 16D. Support of the span on abutments VU1, VU2 through movable supporting parts type T2PL according to N 2120РЧ, developed by JSC Transmost. Holes Ø25mm are installed in the lower chord and support sheet of the span for fastening supporting parts. The position of the supporting parts on the grillage of the temporary abutment is fixed with stops. On abutments No. 0" and No. G, the span is supported by fixed supporting parts type T2N according to project No. 2120РЧ, developed by JSC Transmost. Holes of 25 mm are made in the lower chord and support sheet of the span for fastening the supporting parts using bolts.

The abutments for the 3rd track are without grillages, on a pile foundation of 2 piles. Piles made of pipe Ф630х8, length 7.4 m, steel VSt20. Bollards for supporting spans made of I-beams No. 55B1

The abutments for the 1st and 2nd tracks are without grillages, on a pile foundation of 4 piles. Piles made of pipe Ф630х8, length 7.4 m, steel VSt20.

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

Construction site organization

For the entry of construction equipment on both sides of the overpass through I Nth way Technological races are organized. To allow equipment to enter between tracks, technological floorings are installed across the railway tracks, which are used only during the “window”.

Between the tracks, two technological platforms are set up for the operation of an excavator with attachments. Parking of an excavator between tracks is carried out with strict adherence to the clearance of the building approaching along adjacent tracks.

To serve the personnel, an area with cabins, toilets and a foreman's room is set up.

Technological sequence of work

Work on the installation of temporary bridges is carried out during “windows”, according to the schedule for their provision, developed in the PPR.

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

. Stage I. Construction of a pile foundation for temporary bridges.

Temporary package span structure (TPS) under Shy way rests on a pile foundation in the amount of 2 pieces. from each side. The piles are meth. a pipe 630 mm in diameter and a wall thickness of 8 mm, 10 m long. Before the start of the main “window”, the piles are transported to the work site by an automatic rail with ADM-4 and unloaded between the tracks, observing the clearance of the building.

After the start of the “window”, the pile is vibrated to the design mark using an excavator with a Movax SP-40F vibratory driver with a side grip. During work on the site, the contact network is not dismantled.

In this way, a pile foundation is installed for the temporary span of the third track. When the excavator is operating, the clearance along adjacent tracks is not disturbed.

Similar technological sequence construction of a pile foundation and temporary package spans of tracks 1 and 2.

. Stage II. Installation of support superstructures and temporary package spans.

Before the start of work in the main “window”, transportation to the work site, unloading and placement on the site of technological equipment, support head structures, longitudinal and transverse crossbars are carried out. As well as cutting continuous strands in the work area onto inventory rails 3x12.5 m along each track and collapsing them into rail joints.

In the main “window”, with the closure of traffic along the Sh-th track, the track-laying crane UK-25SP is used to dismantle the upper structure of the track and load the links onto the cover platform. After dismantling the first link, the excavator begins dismantling the soil to the design level for cutting the pipe piles, installing their heads and support beams.

After dismantling the upper structure of the track, the track-laying crane is retracted to a safe distance of 50 m. After which, a team of workers begins cutting out the ballast trough.

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

After cutting out the ballast trough, a track-laying crane is brought in and the existing span of the 3rd track is torn off and dismantled and loaded onto the cover platform.

After dismantling the existing span of the 3rd track, the tracklayer is removed to a safe distance, the platform is uncoupled from the superstructure of the track and the existing span. Next, the platform is transported to the unloading site at the base of the local IF or PMS.

After that, the second set of cover platforms with a submerged temporary package span and bridge deck are delivered to the crane.

In parallel with these works, the construction of the pile foundation and the installation of the support beam continue, as well as the cutting down of the top of the cabinet wall using a backhoe loader with a hydraulic hammer attachment to the design level. The crossbar is mounted by the excavator boom from the inter-track to the design position.

After completing the construction work and cutting down the concrete from the top of the cabinet wall, a track-laying crane is brought in, which mounts a temporary package span structure on the track axis.

At the final stage, the sinuses are filled with crushed stone, the bridge deck, security devices are installed, and the contact network is restored.

The installation of temporary bridges under the I-th and N-th tracks is carried out in a “window” with the closure of traffic on both tracks. The clearance along the Sh-th path is not violated.

The remaining work is carried out in the same sequence.

There are various situations when it is necessary to completely or partially dismantle a bridge: repairing the road surface on it, carrying out a comprehensive reconstruction of the territory, building new roads (due to which the bridge is no longer needed). There are a number of nuances that you should pay attention to when carrying out these events.

First of all, the selection of technology depends on the task and technical specifications execution of work:

• What type of bridge is to be dismantled? This can be either a structure on water bodies, with supports at the bottom of reservoirs, or a land road bridge (overpasses, interchanges and other road structures).
• What material is the structure made of? This is a fundamental issue when choosing dismantling methods. Most often, two types of bridges are used: reinforced concrete and metal, but sometimes wooden ones can also be used.
• What kind of dismantling is necessary: ​​complete or partial? In case of complete demolition, powerful destructive methods are used, for example, explosive technologies or the destruction of supports using heavy equipment. If you need to remove, for example, only the top covering, leaving the supports and frame, thinner solutions, like Brokk robots, are suitable. For example, using the given link you can order bridge dismantling using robots of this brand.
• What is the operating mode of the facility? In most cases, bridges to be demolished are completely closed and traffic on them is prohibited. However, sometimes, if we are talking about important junctions, their complete closure is impossible. Then partial dismantling work can be carried out, when one lane is open, and the top covering is removed on one of the lanes for the purpose of subsequent repairs.
• What is the condition of the structure? The more dilapidated and unsafe the condition of the object, the higher the precautions required during demolition. In addition, the condition directly affects the choice of the optimal dismantling method.
• Do structures require access from water? The need to perform work on water significantly complicates the task. In some situations, high-tech methods using diamond cutting cables that cut supports underwater are even justified.

About the importance of safety precautions

Any dismantling work is in one way or another associated with an increased risk to the lives of personnel. Therefore, it is important to develop dismantling technology, consider safety precautions and strictly adhere to these standards when performing all types of work.