Method for strengthening cracked metal thin-wall element of span structures of bridges
SUBSTANCE: strengthening method includes drilling a hole at the crack mouth, applying a solder, installing strengthening elements in the form of straps installed on both sides of the metal element, and local heating to the melting point of the solder. The hole in the crack mouth is drilled with a diameter of at least two sheet thicknesses, a paste-like solder is applied to the strap surface, and a mushroom-shaped strap is installed by inserting its stem into the hole. The clearance between the strap stem and the beam wall in the hole is 0.2-0.25 mm, the pressing force is not less than 0.2 MPa. The strap due to the solder adhesion with the base metal is involved in the joint work with the main element. Its cross section is not only not weakened, but is also strengthened by increasing the cross-section with the straps. While heating, in the hole area (the metal is expanded into the hole), additional compressive stresses slowing downing the crack development are created.
EFFECT: increasing the operational reliability of a span structure with a crack in the wall of the main beam, which extends predominantly from a seam fastening a stiffener thereto.
SUBSTANCE: first, a collar beam is extended on both sides of supports. After that, the lower flange of the existing structure is reinforced and lifted and rollers are installed under the lower flange. Then, jacks are installed and the existing superstructure is relocated with jacks in transverse direction of bridge supports. After that, rollers are removed and traffic flow is arranged on the relocated existing superstructure. After that, on the free part of the supports with the extended collar beam, near the relocated existing superstructure there installed is a block of the main beam of the first part of a new superstructure; then, the next block is installed, and blocks of the first part of the new superstructure are combined. After that, a cantilever orthotropic plate is installed and the first part of the new superstructure is provided with road pavement. Then, traffic flow is shifted to the first part of the new superstructure. After that, the existing superstructure is removed. Removal of the existing superstructure is performed at several stages: first, cantilevers are removed; after that, reinforced-concrete slabs are cut and removed; then, each beam is removed separately. In the place of the removed existing superstructure there installed is the block of the main beam of the second part of the new superstructure; then, the next block is installed, and blocks of the second part of the new superstructure are combined; after that, a cantilever orthotropic plate is installed. The first part of the new superstructure is combined with the second part of the new superstructure with a reinforced-concrete slab and provided with road pavement and enclosures.
EFFECT: improved method.
2 cl, 8 dwg
SUBSTANCE: method to expand a bridge clearance using a cable-stayed system, in process of which a split span is changed into a non-split span, is characterised by the fact that additional elements are installed, namely, traction rods, metal plates, then pylons with cable stays are installed. Traction rods are installed between adjacent beams of the split span and are fixed, then metal plates are installed in areas of connection of adjacent beams and a support crossbar, and they are combined with adjacent beams and crossbars of supports by means of an anchor joint. Then pylons are erected at both sides of the span, with a support against the area of ground under the bridge, afterwards cable stays are installed and tightened, and supports are dismantled.
EFFECT: increased reliability.
6 cl, 5 dwg
SUBSTANCE: method includes installation of additional elements: amplifying crossbars, pylons, additional transverse and longitudinal beams and cable guys; which are combined with elements of the existing bridge structure. At first the upper part of each support is reinforced with a reinforcing crossbar, afterwards pylons are installed in pairs with crosspieces in the upper part of pylons on side protruding parts of the lower parts of supports, in the area of main vertical beams. Then they install additional transverse beams and cover them with additional longitudinal beams, then they install devices for fastening of cable guys, afterwards they tighten and fix cable guys, and then lay the door surface and install barriers.
EFFECT: invention provides for the possibility to expansion and reinforcement of a bridge structure without termination of its operation.
2 cl, 7 dwg
SUBSTANCE: in a device of structure reinforcement with the help of composite material tapes, comprising a composite material tape, ends of which are connected to anchor assemblies comprising support plates fixed on a reinforced concrete beam, add-on plates to clamp ends of the tape, at the same time one of anchor assemblies is made as capable of connection to a system of lengthy tape tensioning in longitudinal direction, the composite material tape is equipped with ends installed on it and connected to brackets installed on support plates of anchor assemblies, and connection of ends with brackets is made in the form of hinged joints, which allow for rotation of tape ends relative to the beam in case of its deformations. Besides, one of tape ends is made with an eye that carries a cardan connected by other end to the eye of the bracket in one anchor assembly, and the other end is made with a threaded hole for a threaded rod, passing with a gap via a hole of the bracket of the other anchor assembly, at the same time the threaded rod by one end is screwed into the threaded hole of the end, and on the other end it carries washers, a nut and lock-nut for its fixation relative to the bracket. Besides, ends are made with flat sites and are equipped with add-on plates for fixation on the tape by means of bolts, at the same time on clamping surfaces of add-on plates and flat sites there are accordingly grooves made, which stretch in direction perpendicular to the longitudinal line of the lengthy tape and arranged in parallel to each other and preferably with the same pitch between them.
EFFECT: development of a device for reinforcement of a building structure by reinforcement from polymer composite material on the basis of high-strength artificial fibres, providing for reduced costs for installation and operation, having increased reliability in operation, increased service life.
2 cl, 5 dwg
FIELD: construction, road engineering.
SUBSTANCE: method for dismantling of a T-shaped frame in a bridge span formed by box-shaped blocks assembled as hanging over and attached to the support head with bundles of prestressed reinforcement, consists in pre-dismantling of the bridge deck, alternate mounting to the crane and cutting of box-shaped blocks of consoles of the T-shaped frame and their removal from the building site. On consoles of the T-shaped frame they mount standalone mounting rails with crossbars, they anchor one end of the standalone installation of beams on spans and rest it by supports on the top plate of the span. After that they attach end box-shaped blocks of consoles to cross beams, and cut them along the axis of joining with the adjacent box-shaped blocks, and then one of the cut blocks is slung to the crane and removed from the construction site. The vacated standalone mounting beam is moved to the new parking lot, the next box-shaped block is attached to its cross beam, the second cut block is slung to the crane and removed from the construction site, and then the vacated standalone mounting beam is moved to the new parking lot, and the next box-shaped block is attached to the cross beam. The process of dismantling the span continues in a similar manner until it reaches the ends of the standalone mounting axis of the support beams, and then the ends of the standalone mounting beams are combined together to form a single mounting rail, and it is anchored to the support, then the process of dismantling of the span continues the same way. Prior to attachment of the box-shaped blocks to cross beams and cutting of segments of span blocks they strengthen the joints of the span blocks by drilling holes in these joints, introduction of adhesive into their cavities and plugging these holes with metal dowels. The mounting beam for carrying out the method includes a mobile scaffold, a cross beam with rods, an anchor attached to the span and supports. The mounting beam made as composite of two standalone mounting beams, each provided with scaffolds, a crossbeam with rods, an anchor attached to the span and supports, besides, self-mounting rails are combined into a single mounting beam during dismantling of the span when the free ends of the standalone mounting beam reach the axis of the bridge supports. Anchors in the single mounting beam are fixed on the bridge support.
EFFECT: improved design.
4 cl, 6 dwg
SUBSTANCE: method to disassemble a bridge span formed from blocks of T-shaped frames with closing elements assembled as suspended, consists in preliminary dismantling of a deck, alternate fixation of blocks to a weight-lifting device and cutting of blocks on cantilevers of the T-shaped frame and their lowering and removal from the construction site. Previously pier blocks of T-shaped frames are rigidly fixed to templates, a launching rail is installed on the upper slab of the span, and a device for disassembly of the span is mounted along the bridge axis, which comprises a bearing beam with a launching nose, flexible suspensions and jacks with a flexible stem. Then the device for disassembly of the span is moved along launching rails, covering spans of at least two adjacent T-shaped frames, afterwards blocks of one of T-shaped frames and a closing element are fixed with the help of flexible suspensions to the bearing beam, and the closing element is fixed to flexible stems of jacks, cut and lowered with the help of jacks. Extreme blocks of cantilevers of the T-shaped frame are fixed to flexible stems of the jack, and these blocks are cut and lowered with the help of jacks, and then jacks are moved to a new position, and their flexible stems are fixed to extreme blocks of cantilevers of the T-shaped frame. Afterwards the process of disassembly of the T-shaped frame is continued in a similar manner, at the same time after disassembly of blocks of the first T-shaped frame in process of disassembly the bearing frame of the device is moved to the following span, and similarly the next T-shaped frame is disassembled.
EFFECT: increased operational reliability.
4 cl, 10 dwg
SUBSTANCE: method to eliminate deformations of bridge crossing abutments includes increasing the support area of abutments by erection of a solid shell around them. Previously along the contour of the support part of shells there are waterproof screens erected by means of injection of a water-impermeable composition into soils of abutment bases, monolithic reinforced concrete shells are erected at three sides of each abutment from the level of its foot, shells are connected with each other by a spacer beam. In support parts of the shells, every of which has width exceeding the width of the appropriate abutment, there are through holes made, through which fixing solutions are injected into the soil base of abutments.
EFFECT: increased efficiency and reliability of elimination of deformations of bridge crossing abutments erected on a soil base with insufficient bearing capacity.
SUBSTANCE: reinforcing structure of a pier table of an arched bridge span includes arches that rest with their ends against permanent bridge supports, support stands, a beam grid, made of longitudinal and transverse beams and longitudinal beams of filling between spans, resting on longitudinal beams,- and a traffic area with movement joints. Under the transverse beam, which is extreme in the span and adjoins the pier table, there is a flat reinforcement truss mounted, attached to support stands, between the extreme transverse beam in the span that adjoins the pier table and the flat reinforcement truss there are additional longitudinal beams that rest on the flat reinforcement truss and are brought to the transverse beam arranged in the middle part of the span. On additional longitudinal beams there are additional transverse reinforcement beams installed, against which ends of longitudinal beams of filling between spans via tangential support parts of higher movements rest, and via wedged packages of steel sheets - ends of existing longitudinal beams adjoining the pier table of the span. The flat reinforcement truss has bearing capacity that is not lower than the bearing capacity of the transverse beam, which is extreme in the span and adjoins the pier table.
EFFECT: higher bearing capacity of an arched bridge span.
2 cl, 6 dwg
SUBSTANCE: in method for formation of spherical contact surface of bridge support part, welding is carried out with multiple electrodes to form circular rolls into separate baths with a height that makes it possible to form spherical surfaced of welded layer, and further cavities between applied rolls are filled, at the same time electrodes are moved with the speed determined according to the formula where υe - speed of electrodes feed; re - electrode radius; rs - stock radius; υw - speed of welding; h - maximum height of welded layer; Ka - allowance for processing; ne - number of electrodes; np - number of welding passes. In process of welding electrodes are used with diametre that increases from stock periphery to its centre. End rolls are applied concentrically with alternating pitch that reduces from stock periphery to the centre. In process of welding electrodes are arranged at the angle of 20-30 to plane of stock placement. Cavities between primarily applied rolls are filled with filler material. Stock of support part is represented by part with flat welded contact surface.
EFFECT: invention eliminates flowing of melted metal from curvilinear surface of shaped ball segment and minimised allowance for further mechanical processing as a result of staged application of melt metal layer onto formed surface.
7 cl, 8 dwg
FIELD: construction, road construction.
SUBSTANCE: invention pertains to the field of reconstruction of bridges with a concrete slab span continuous structure. The technical outcome is the increase in effectiveness of replacing supports of a continuous superstructure of a bridge due to the accuracy of installing it into the projected position and increased reliability due to lowering of the resultant stress in the superstructure during replacement of the supports. The technique of replacing the supports of the continuous superstructure of the bridge, implemented successively on each support of one superstructure and including construction of a device for temporary support of the superstructure in the form of a concrete pier with a dividing polymer layer for setting of the concrete of the pier with concrete support, and mounting on the pier, a sliding device in the form of a beaming metallic sheet with antifriction material on it. On the surface of the supports on the spots for mounting jacks and temporary support devices, concrete is removed down to the protective layer of the reinforcement. The jacks are mounted on a metallic sheet. The gap between the upper sheets, mounted on the jacks and the superstructure is filled with a plastic material. The jacks are joined to the battery for connection to different pumping stations. Lifting of the superstructure is done for a value not more than 10 to 15 mm, after which it is remounted on the device for temporal support. By removing the jacks, the old supports are removed. The superstructure is then raised on the jacks again and extra metallic sheets are cleared. The superstructure is lowered into the projected position. After mounting the new supports and strength gain of the plastic material in the gaps, the superstructure is raised, and the device for temporal support is dismantled.
EFFECT: increased effectiveness of replacing supports of a continuous superstructure of a bridge.
FIELD: bridge building, particularly for building motorway bridges and pedestrian overpasses, mainly of wood and metal.
SUBSTANCE: span structure has wooden deck having thickness changeable along span length. The greatest thickness is in span center part and the lesser one is at span edges. Deck forms extensions inclined to transversal deck axis and transversal pre-tensioned reinforcement located inside deck, supporting subdiagonals located under deck and arranged coaxial to longitudinal deck edges. Rigid inclined transversal tie system formed at each deck end part consists of upper and lower belts, struts and post. Upper belt of each tie system rests upon corresponding inclined deck extension, lower belt thereof is pivotally connected to subdiagonals by ends thereof. Post extends in tie system plane along line laying in vertical longitudinal axial deck plane and rigidly secured to tie system belts by ends thereof. Struts are connected by their ends to lower belt and to lower post end and rigidly secured to corresponding end parts of upper belt by another ends thereof. Deck thickness in span is 1.6 - 1.9 deck thickness at deck ends.
EFFECT: increased load-bearing capacity of span structure, its flexural rigidity and torsional rigidity in transversal direction.
2 cl, 2 dwg
FIELD: building and reconstruction of artificial structures, particularly bridge and elevated road reinforcement.
SUBSTANCE: device includes a bundle of ropes, rope deflection means with posts and supports with anchoring rope clamps. Each rope deflector is provided with slide bearing made as bush connected with guiding post and with rope bundle.
EFFECT: improved operational reliability and reduced cost of bridge maintenance.
2 cl, 3 dwg
FIELD: building, particularly for bridge reconstruction along with reinforcing and widening thereof.
SUBSTANCE: reinforced concrete bridge comprises posts having support diaphragms and cross-bars having box-like cross-sections with longitudinal multi-strand prestressed reinforcement members secured by ends thereof to corresponding ends of cross-bars and supported by them through intermediate piers. Installed in cross-bar cavities near ends thereof between upper and lower shoulders of cross-bars is at least one additional wall extending along bridge axis. Longitudinal prestressed reinforcing members are secured to additional walls by their ends. Each additional wall is connected to upper and lower shoulders of cross-bar through prestressed members located near end surfaces thereof. Intermediate piers are arranged above support diaphragms of posts inside box-like cross-bar.
EFFECT: increased load-bearing capacity and traffic capacity, increased residual bridge life by depreciation and obsolescence criteria.
2 cl, 3 dwg
FIELD: bridge building.
SUBSTANCE: proposed method of replacement of bridge framework includes mounting of existing bridge framework to be demounted onto floating supports with subsequent disassembling of frame using at least one traveling load-lifting crane, loading of disassembled of framework on watercraft, carrying them to bank and mounting of new bridge framework. Novelty is that cross shifting of framework to be demounted is done, new bridge framework is mounted, two floating supports are brought under bridge framework to be demounted and as bridge framework members are being demounted, each floating support at side of demounted section after demounting of said section is moved along demountable bridge framework and is set behind second floating support. Demounting of sections of existing framework is done from top to bottom by cutting out linear members of upper belt, then posts, hangers, braces and then members of lower belt.
EFFECT: improved reliability, reduced expenses, labor input and time taken for replacement of bridge framework owing to demounting of bridge framework from one side with use of movable floating supports for resting of bridge framework to be demounted.
5cl, 6 dwg
FIELD: building, particularly bridges with reinforcement and widening.
SUBSTANCE: frame bridge comprises posts with support diaphragms and cross-bars of box-like cross-section having longitudinal pre-stressed reinforcement members connected to cross-bar ends by end parts thereof and supported by cross-bars by means of intermediate supports. Each intermediate support is formed of fixed panel-like part joined with outer face of cross-bar wall and with lower face of concreted console of roadway cross-bar part panel. Movable parts of intermediate supports are separate for each branch of longitudinal pre-stressed reinforcement member passing into curvilinear thick-walled tube reinforced with longitudinal rib to which upper end of pre-stressed drawbar is connected. Lower drawbar end is releasably attached to lower face of fixed panel-like part. Longitudinal reinforcement members are located under concreted consoles of roadway part panel and are inserted in channels made in bosses of concreted roadway part cross-bar panel console and secured to corresponding cross-bar ends by anchors and to intermediate supports.
EFFECT: increased load-bearing capacity and throughput; increased residual bridge life according to deterioration and ageing criteria.
FIELD: methods or apparatus for repairing or strengthening existing bridges.
SUBSTANCE: method involves fastening the first ends of main coal-plastic plates to beam ends; stressing the main coal-plastic plates by moving the second ends thereof towards beam center; gluing the stressed coal-plastic plates to above beam; gluing additional coal-plastic plate to the beam after stress application to beam center with the use of anchoring boxwoods, which are pulled one towards another, and after glue strength development up to design strength. Additional coal-plastic plate is arranged above main ones so that additional plate covers gap between main plates and ends of above plates at beam center. After hardening of glue located under additional plate anchoring boxwoods are released and demounted.
EFFECT: increased operational reliability and improved bridge appearance.
2 cl, 1 dwg
FIELD: building, particularly artificial structure construction and repair, namely reinforcement devices for composite bridge structures.
SUBSTANCE: device includes strand bundles, rests, anchoring members and fastening pins to connect the rests to beam. The device comprises additional rest having plate, which cooperates with end beam part and pre-stressed control rods fastened to plate and pins correspondingly.
EFFECT: increased load-bearing capacity and reliability of the bridge, reduced costs of bridge maintenance.
FIELD: bridge building, particularly bridge reconstruction.
SUBSTANCE: method according to the first embodiment involves erecting additional support members in proximal vicinity to existent bridge pier; demounting beam span structure during traffic interruption period; mounting new span structure supported by additional support members. The additional support members are made as posts constructed from both span structure sides out of the bounds of the existent bridge. After that composite or monolithic girth rail is erected on the post and cabinet-type blocks are installed upon the girth rail. Cabinet-type block wings abut the piers. Newly-built short span structures are mounted so that the span structures rest upon the girth rails. Method according to the second embodiment involves removing embankment ground outside bridge piers and erecting posts with composite or monolithic girth rails out of the width of the existent bridge; removing span structures; disassembling the existent piers and installing cabinet-type blocks on the girth rails; erecting new elongated span structures supported by girth rails of the posts. Method according to the third embodiment involves forming additional support members made as posts erected from span structure side out of the bounds of existent bridge; mounting composite or monolithic girth rail on each post; mounting new span structures having lengths equal to that of demounted ones and supported by the posts, wherein cantilevered parts of the span structures abut walls of existent piers by ends thereof.
EFFECT: increased technological effectiveness and reduced time of bridge reconstruction.
6 cl, 8 dwg
FIELD: bridge building, particularly to reconstruct and reinforce little bridges and pipes in active railroad and motor roads.
SUBSTANCE: method involves installing removable form inside bridge opening to create reinforcement structure having shape close to bridge opening shape and filling gaps between removable form and bridge pier with concrete mix and reinforcement to form new span structure. Foundation, namely concrete base is arranged, then space between existent piers and form is filled with concrete mix to create reinforcement structure having walls integrally connected with existent piers by tie members, for instance by anchoring rods. Air gap is created between existent span structure and top of new span structure to provide free deflection of existent span structure. After strength development in concrete mix old span structure is disassembled and new road pavement is formed so that the road pavement is supported by new span structure.
EFFECT: possibility of normal bridge usage during bridge reconstruction, reduced material consumption and provision of maximal throat area of bridge opening.
3 cl, 1 dwg, 1 ex
FIELD: construction, particularly artificial structure, preferably reinforced concrete bridge, repair.
SUBSTANCE: repair method involves connecting lower belts of adjacent beams with metal sheets; securing the metal sheets to the beams by means of bolts; installing covering plates in spaces between adjacent beams so that the covering plates may be connected with beam walls; laying new concrete panel on the structure; providing development of new panel concrete strength; releasing metal sheets from beams by unscrewing the bolts; removing the covering plates; forming new paving; applying load equal to 0.25-0.35 of temporary load to each beam; securing metal sheets to beams to provide design load withstanding. The load is symmetric with respect to transversal plane of metal sheet symmetry. The panel is formed of fiber reinforced concrete.
EFFECT: increased simplicity and decreased operational costs, as well as reduced concrete panel deformation.
3 cl, 5 dwg