When placing the crane on the ground (Fig. 5, a), the mounted beams are stored next to the crane so as to ensure installation by rotating the crane boom by 180°. It is possible to install beams “from wheels” without setting up a warehouse for beams on the construction site.

The beam intended for installation is slung, lifted, brought into the span by turning the crane boom and smoothly lowered onto the supporting parts, then freed from the slinging devices. The crane is moved to a new position and the installation of the next beam begins. The position of the crane and the location of the beams prepared for installation are selected in such a way as to ensure a minimum reach of the crane boom and eliminate the need to move it with a load.

Rice. 5 – Schemes for installation of beam reinforced concrete spans using jib cranes: 1 – crane; 2 – traverse; 3 – installed beam; 4 - installed blocks spans; 5 – beams prepared for installation

If the lifting capacity of one crane is insufficient for installation, two cranes are used to lift the beam from both ends simultaneously. The mounted beam is located in front of the cranes. Raising it first at the minimum boom reach, the beam is inserted into the span and installed on supports, increasing the reach of the crane booms. If the lifting capacity of the cranes does not allow installation of the beam at the required boom reach, the mounted block is first lowered at the maximum possible boom reach, then the cranes move forward, the beam is raised again, repeating the operations performed.

Superstructures can be installed with jib cranes from the side (from the field) and from the front (Fig. 6). Slinging of blocks is carried out using standard and special slings and traverses. At the same time, both slings and traverses must be designed with a margin: slings - with 6...8-fold, traverses - with 2-fold.

Rice. 6. Installation of spans using jib cranes:

a - with one crane from the parking lot along the axis of the bridge when turning 180°; b - with rotation and movement; c - from the side with a turn; d - from the side with lifting and moving; d - two taps; 1 - initial position; 11 - position of the cranes at the time of installation of the superstructure; 1 - superstructure block; 2 - tap; 3 - supports; 4 - bridge axis

Do you know how many nuances are important to take into account when designing bridge structures? For example, how the method of installing the span is selected. The accuracy of calculations directly depends on the experience of the organization. Our portfolio contains more than 50. We guarantee quality.

After production of transport and preparatory work direct installation of structures begins . Depending on the project and existing technical specifications installation of bridge spans can be done in several ways.

Technologies for assembling spans

Assembly on scaffolding. This option involves the use of spans with main through-type trusses, the elements rest on the scaffolding at each node. Installation scaffolds are erected on temporary supports from universal designs and other inventory property. Bridge inventory structures are made of rolled metal, in some cases it is allowed to use separate wooden elements. Depending on the technology, it can have several types:

Mounted or semi-mounted assembly. The work is carried out from the supports into the span between them, the structure works like a cantilever. Elements in some places have emphasis, and in other places they sag. Semi-mounted assembly is used in cases where it is considered inappropriate to install temporary supports for some reason. Sometimes hinged assembly is carried out using the balancing method - installation is carried out simultaneously on both sides of the support.

Installation using a longitudinal slide. It involves the sliding of spans assembled on a slipway using rolling and pushing devices.

Crane assembly. Installation of metal spans buildings carried out using various crane equipment, allows you to minimize construction time installation work.

Installation using floating equipment. It is used during the construction of multi-span bridges when it is impossible to install temporary supports in the river bed.

The company "TRANSSTROYPROEKT" provides qualified assistance in choosing the best way carrying out construction work(), which makes it possible to reduce the cost installation of bridge superstructure beams and speed up the commissioning of the facility. This takes into account existing rules and recommendations government agencies. The pre-selected method is agreed upon with the customer and, after approval, the method is included in the design and working documentation, including SVSiU. Among the ones we have completed design work taking into account the choice of method for installing spans, such objects as, and many others.

Construction time is significantly reduced when using all-transportable or large-block structures and installing them with cranes.

The installation of spans can be carried out using jib, gantry, cantilever cranes, as well as crane units. After installing the blocks, the position of the structure in plan and profile and the arrangement of joints are verified.

Sliding of spans

During the construction of metal bridges, longitudinal and transverse sliding of spans occurs.

Longitudinal slide used for installation of spans assembled on embankments along the axis of the bridge. When sliding small spans, slides made of channels, steel sheets or angles are attached to the bottom of the structure. The sliding structure is moved along the rails.

Rice. 9.19 – Diagram of sliding of metal spans with a solid wall: 1 – installation crane; 2 – trolley for moving the superstructure on the embankment; 3 – dead end for catching carts; 4 – carriages; 5 – avanback; 6 – temporary overlay

The assembly of spans can be carried out on scaffolds parallel to the axis of the bridge. In this case, to install spans in the design position, use transverse slider. To do this, under the supporting units of the span, piers are built from inventory metal structures, along which the lower rolling path is laid. The upper knurling paths are secured to the transverse beams. After moving to permanent supports, the span structure is jacked up and installed on the supporting parts.

Installation of spans using floating equipment

Installation of span structures using floating means allows for assembly to be organized away from the bridge alignment and, for multi-span bridges, can significantly reduce construction time.

The spans are assembled on solid scaffolds on the downstream side of the bridge under construction. To roll out spans into the channel and install them on floating supports, piers are arranged along which the assembled structure is moved transversely (more often) or longitudinally.

34. Methods for installing steel bridge spans using cranes

For installation of metal spans uses heavy-duty cranes:

floating with a carrying capacity of up to 1000 tons or more;

self-propelled railways up to 250 tons;

booms on automobile and crawler lifting capacity up to 170 tons;

cantilever railways with a carrying capacity of up to 130 tons;

self-propelled gantry with a lifting capacity of up to 65 tons;

Jib railway cranes can install metal solid-walled span structures of railway bridges with a ride on top up to 45.8 m long in one block, and up to 55.8 m long - in two blocks (for this purpose, a temporary support is built in the span). The GEPC-130 has the ability to rotate the boom with a distance of up to 5.3 m from the track axis.

The crane is used to install enlarged spans, buildings or blocks on the approach to the bridge. They are laid out on sleeper cages along the approach embankment. The block is slung to the hook, the crane boom is rotated to the axis of the bridge, and the locomotive delivers the crane along the bridge, riding on top, to the place where the block is installed. After installing and securing the block to the supports, the crane returns back for the next block. Thus, installation is carried out “from the head”.

Sometimes a cantilever crane is used to install an enlarged (several panels long) spatial block of a superstructure with a span of 55, 66 and even 88 m. Then they are mounted using a hinged method (the number of intermediate supports in the first span is naturally reduced). The general diagram of the installation of such a span using a GEPK-130U crane is shown in (Fig. 6.16).

Rice. 6.16 – Schemes for installing spans with a ride on the bottom: a – solid span; b – large blocks; 1 – console crane; 2 – span; 3 – superstructure block; 4 – temporary span; 5 – bridge support; 6 – temporary support

Railway jib cranes EDK-500, EDK-1000, EDK-2000 with a lifting capacity of 80, 125 and 250 tons, respectively, etc. are widely used for the restoration and installation of single-span bridges, as well as overpasses (Fig. 6.17). To operate, it needs railway access and the ability to use outriggers (in this case, the crane’s maximum lifting capacity is realized).

Rice. 6.17 – Scheme of installation of blocks of spans using the EDK-1000 jib crane: 1 – crane; 2 – new span; 3 – old span; 4 – block prepared for supply under the tap; 5 – block installed on supports

Installation “from the head” is limited by the lifting capacity of the cranes, which decreases significantly with increasing length of the span. If it is possible to use outriggers (outriggers) of the crane, it is necessary to check the load-bearing capacity of the span for outrigger pressure during installation. Domestic and foreign road jib cranes on automobile, pneumatic and crawler tracks, as well as on special chassis in last years widely used due to their significant load-carrying capacity. They are especially often used in the construction of road bridges, overpasses and overpasses for installation both “from the top” and “from below” (from under the bridge). A passage is arranged along the mounted span, and a crane (crawler, for example) is installed in the area of ​​the support of the span being mounted. A block of the span structure is transported under the crane by a beam carrier, it is slung and mounted by turning the boom. It is imperative to check the span with non-monolithic beams for the load from a crane with a load.

Gantry cranes(Fig. 6.18) are characterized by a constant load capacity and the ability to move with a load. If the lifting capacity of one gantry crane is insufficient, the blocks can be mounted using two.

Rice. 6.18 – Scheme of installation of road steel-reinforced concrete 42-meter span structures using a K-451M gantry crane: 1 – metal structures warehouse; 2 – platform for installation of superstructure blocks; 3 – tap; 4 – block installed on supports; 5 – mounted span; 6 – crane trestle; 7 – driveway highway; 8 – stand

Installation with gantry cranes is advisable in urban environments, on dry floodplains and non-navigable rivers, when low-water overpasses and crane tracks can be installed. The height of the main supports should not exceed 15 m. The cranes are placed on the approach embankment, which is not even filled to the design levels. Using a gantry crane, it is relatively easy to erect supports, install spans, and lay a prefabricated roadway slab. Floating cranes with a carrying capacity of 100, 200, 350 tons - self-propelled and fully rotating, it is especially advisable to rent them in large port cities. There are also floating cranes with a lifting capacity ranging from 500 to 3000 tons, which are usually used to lift sunken ships. In the 1980s, Mostostroy-6 used a floating crane with a lifting capacity of 1000 tons for the construction of a bridge across the river. Neva near the village Maryino, Leningrad region. The cost of renting such cranes is quite high, but the technology is significantly simplified. Assembly is carried out on shore in the operating area of ​​the floating crane, after which the enlarged unit is transported on the crane hook to the installation site. Blocks can also be delivered to the crane on floating craft (barges, dinghies). The crane is secured in advance in the water area near the future bridge with Admiralty-type anchors and suction anchors made of reinforced concrete. Floating cranes are divided into general-purpose floating cranes, specialized prefabricated cranes and cranes installed on floating craft. General-purpose floating cranes are self-propelled full-rotary or fixed-rotary cranes with a lifting capacity of 5 up to 1000 tons. In bridge construction, they are used for the construction of supports and installation of spans. In (Fig. 6.19), as an example, a full-rotating floating crane with a lifting capacity of 5 tons is shown, and in (Fig. 6.20) a fixed-rotating crane “Vityaz” with a lifting capacity of 1000 tons is shown. How As a rule, floating cranes of this group are rented in ports.

Figure 6.19 – Floating crane PKL-5/30: 1 – rocker arm; 2 – thrust for changing the boom radius; 3 – engine room; 4 – rotary mechanism

Rice. 6.20 – Floating crane “Vityaz”: 1 – pontoon; 2 – winch for changing the boom reach; 3 – winch; 4 – auxiliary lift winch; 5 – ship crane; 6 – main lift winch; 7 – boom; 8, 9 – suspensions of the main and auxiliary lifts, respectively.

Specialized prefabricated floating cranes are produced specifically for the construction of bridges. Known floating cranes designed by the Transmost Institute are PRK-30/40, PRK-100, etc. Their characteristics are given in Table 6.3. The general view of such a crane is shown in (Fig. 6.21). The movement of floating cranes across the water area is carried out by anchor winches (Fig. 6.22) attached to pontoons. It must be taken into account that floating cranes narrow the river fairway.

Rice. 6.21 – Floating collapsible crane PRK-80: 1, 2 – suspensions of the main and auxiliary pulleys, respectively; 3 – jib guy; 4, 5 – winch cable of the auxiliary and main pulleys, respectively; 6 – swinging stand; 7 – jib pulley; 3 – valve block; 9 – dinghy; 10 – power plant; 11 – cargo winch; 12 – support unit; 13 – control cabin; 14 – boom; 15 – installation of a manipulator winch

Rice. 6.22 – Floating crane berthing diagram: 1 – floating crane; 2 – anchor winches; 3 – braces made of steel ropes; 4 – reinforced concrete suction anchors; 5 – support

TECHNOLOGICAL CARD No. 2

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

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

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

CHIEF ENGINEER OF THE INSTITUTE

"ORGTRANSSTROY" (B.A. SKLYADNEV)

TECHNOLOGICAL CARD No. 2

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

I. Scope of application

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

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

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

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

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

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

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

Under-console dimensions, m:

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

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

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

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

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

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

Counterweight mass, t:

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

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

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

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

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

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

Table 3

Characteristics of supporting parts

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

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

II. Instructions for production process technology

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

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

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

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

Rice. 8. Installation site diagram:

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

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

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

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

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

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

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

Install the supporting parts in the design position;

Bring the crane into working position;

The span is being rigged;

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

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

Rice. 9. Viewing devices on supports:

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

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

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

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

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

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

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

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

Slinging work is carried out in stages:

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

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

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

The movable counterweight is moved and finally installed.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Rice. 11. Overlap expansion joints when connecting spans:

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

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

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

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

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

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

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

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

5. “Rules for the design and safe operation of load-lifting cranes”, M., “Transport”, 1974.

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

7. “Instructions for signaling on railways Union of the SSR", M., "Transport", 1971.

Safety instructions

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

Moving a crane with technical malfunctions threatening traffic safety is not allowed.

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

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

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

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

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

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

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

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

III. Instructions for organizing work

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

VI. Main technical and economic indicators

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

VII. Material and technical resources

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

B. Machines, equipment, tools, inventory

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

VIII. Map of operational quality control of work

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

Note. Thickness cement mortar under the base plate should be within 10 - 25 mm.

Intermediate support diagram

SNiP III-43-75

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