CN105239510A - Dismounting beam support used for high pier small-radius curve cast-in-situ box beam and construction method - Google Patents

Abstract

The invention provides a construction method of a dismounting beam support used for a high pier small-radius curve cast-in-situ box beam, and the construction method comprises the following steps: lifting gantry design and installation, wing plate type carriage design and installation, transversal distribution beam design and installation, dismounting beam assembly, dismounting beam hoisting in situ, support precompression, box beam construction and dismounting beam support dismounting. The high-altitude support integral dismounting fall-down facility and matching technology have the advantages of simple composition, clear bearing, safe and convenient installation, usage and dismounting, fast construction speed, safety and reliability etc.; construction difficulty brought by overlow hoisting height and unstable falling is reduced; influence by the high pier and complex landform condition is overcome; the technology problem of difficult construction in small-radius curve beam using a moving die carrier is effectively solved; social, economical and energy saving benefits are substantial; and high popularization and application value are provided.

Description

For dismounting boom support and the construction method thereof of high pier sharp radius curve cast-in-situ box girder

Technical field

The present invention relates to highway bridge construction field, specifically, relate to a kind of dismounting boom support construction method for high pier sharp radius curve cast-in-situ box girder.

Background technology

In recent years, along with the development of highway communication and urban construction cause, modern high-grade highway and cloverleaf Junction get more and more.Because Curved Beam Bridge can the restriction of adaptation to the ground, atural object well, can construction costs be reduced, meet the continuity of route integral linear, and its structure lines are smooth-going, smooth, lucid and lively, graceful, so Curved Beam Bridge has obtained applying more and more widely.

Current, generally construction with brackets is adopted for high-block bridge curve Cast-in-situ Beam, mainly comprises following construction method:

Prior art one is MSS method, this method is domestic common method, generally be applied to straight line or sweeping curve Cast-in-situ Beam, the Cast-in-situ Beam least radius recording the application MSS method construction that can look into is had to be 600 meters at present, but sweep is less than to the mountain region height pier sharp radius curve bridge of 480m, limit by assembled place, MSS method cannot be used to construct.

Prior art two is full hall scaffold method, and this method force-bearing situation and force analysis simply, but are subject to landform and spanning height restriction comparatively large, and when landform is precipitous, basement process difficulty is comparatively large, and highly larger resistance to overturning is poorer, and safety factor is lower.

Prior art three is middle buttress Bailey truss method, and namely adopt the assembled truss of Bailey beam as rack bearing system, buttress is established in centre.This method force path is clear, and force structure is reasonable; Structure rigid flexible system, impact resistance is comparatively strong, less by the influence of topography.The shortcoming of middle buttress truss method is that middle buttress increases stability with spanning height and reduces, and work high above the ground work amount is comparatively large, easily security incident occurs; Condition of construction is more complicated, some difficulty of lifting component, removes not easily, and every hole rack construction is long for circulation timei; If bracket upright post and temporary rest pier universal rod body are set up, every hole on average needs 120t, and feed consumption is many, and all needs to spell and tear open at every turn, and work consuming is large.

Prior art four is without buttress six or fourmilitary beam falsework method, namely adopts six or fourthe assembled truss of formula military beam is as rack bearing system, and buttress is not established in centre. six or fourlarger and the assembled convenience of formula military beam component, be easier to ensure construction safety, the influence of topography is less.But this method condition of construction is more complicated, some difficulty of lifting component, removes not easily; Machinery uses many, easily mechanical security incident occurs, six or fourwithout the disadvantage of buttress truss method, formula military beam is that truss stiffness by itself is poor, strengthen truss quantity and be then subject to structure space restriction.Though eliminate temporary rest pier recruitment materials, because of truss rigidity and intensity on the weak side, cause truss quantity to strengthen, and near work point six or fourformula military beam quantity is less.

In view of above factor, urgently design a kind of more perfect high-block bridge curve in-situ beam casting method.

Summary of the invention

For solving the problem, the invention provides a kind of dismounting boom support construction method for high pier sharp radius curve cast-in-situ box girder, its design is perfect, easy to operate, good reliability, construction effect are good.

Technical scheme of the present invention is achieved in that a kind of dismounting boom support construction method for high pier sharp radius curve cast-in-situ box girder, and it is characterized in that, this construction method comprises the following steps:

(1) design of lifting gantry and installation, lifting gantry adopts the military pier of finished product equipment eight or three formula assembled, is arranged in pier coping portion groove;

(2) wing bracket design and installation, wing bracket mainly adopts lifting gantry to install, described wing bracket to be connected by two bottom rail spreader beams, four flange plate type brackets being positioned at pier both sides, bracket by a set of wing bracket support, eight bracket pull bars form;

(3) design of transverse distribution beam and installation, transverse distribution beam is become with vertical joint group by dismounting beam crossbeam, lateral;

(4) dismounting beam is assembled, and first smooth assembled place, puts sleeper as temporary support platform according to dismounting beam chord member nodal pitch, it is drawn main truss center line straight to control;

(5) dismounting beam hoisted in position, comprises that dismounting beam promotes, dismounting beam is traversing, promotes the deformation monitoring at gantry, prestressed system, sandbox install, lay i iron;

(6) pre-pressing bracket;

(7) box girder construction, case beam side adopts longitudinal sliding motion formula steel model, and only need low latitude once assembled shaping, concrete placings completes one across rear, can along the longitudinal sliding motion of track piecemeal to next hole across in place, slides to adopt the dilatory or crowbar of hoist engine to prize mode to move;

(8) dismounting boom support is removed, comprise support prestress system remove, falls and remove sandbox, install beam system, end component dismounting, the beam that falls, dismounting transverse distribution beam and wing bracket.

Above-mentioned construction method, is characterized in that, in the design of described lifting gantry with installation steps, lifting gantry adopts the military pier of finished product equipment eight or three formula assembled, is arranged in pier coping portion groove; Pedestal adopts two-layer 5 crisscross formations of eight or three pier 2# iron, is connected and fixed by embedded U-shaped bolt and bridge pier; Column adopts four 1# iron to be fixed on pedestal by longitudinal 175cm, horizontal 150cm spacing; 7 meters long three layers of draw-beam are installed at column top; Different model diagonal brace rod member is adopted to be fixed between column and between draw-beam; Crampon is installed on lifting main beam member, adopts the special high-strength bolt of eight or three pier to be connected to and promotes Gantry top surface of the beam end; Pole together with respectively arranging with arm termination at column root, adopts 10T hoist engine traction 4 and 50 tons of tackle pulley liftings during lifting; Described lifting gantry adopts small-sized gin pole lifting member to complete assembled to Dun Ding, is mainly used in erection & lift wing bracket, transverse distribution beam, sandbox, assembled good dismounting beam.

Above-mentioned construction method, it is characterized in that, in described wing bracket design with installation steps, described wing bracket mainly adopts lifting gantry to install, described wing bracket to be connected by two bottom rail spreader beams, four flange plate type brackets being positioned at pier both sides, bracket by a set of wing bracket support, eight bracket pull bars form, wherein:

Described bottom rail spreader beam is the brace summer of flange plate type bracket, upper load is passed to pier stud, each pier stud arranges two bottom rail spreader beams, every root bottom rail spreader beam adopts two reinforced 40c channel-section steels to be combined into box-structure, longitudinally through pier stud preformed hole, and be welded and fixed with the pre-embedded steel slab in preformed hole, each 400mm of two ends protruded length;

Described flange plate type bracket is made up of 5 pieces of curtain plates and 3 pieces of central layers, central layer adopts the trapezoidal steel plate composition box-structure of spacing 90mm, thick 30mm, the Plate Welding of each cross section of periphery and five pieces of wide 300mm, thick 30mm, two pieces of vertical curtain plates is respectively arranged 4 φ 40mm preformed holes;

Described bracket connects support and comprises transverse horizontal support and oblique bridging, arrange between 2 wing plate brackets of bridge pier homonymy one bridging and together with horizontal brace fixed, connect and support all employing angle steel making, with the curtain plate bolt of flange plate type bracket;

Described bracket pull bar adopts φ 32 fining twisted steel of rank 835Mpa, longitudinally through pier stud and wing plates on two sides formula bracket thereof, both are fixed.

Above-mentioned construction method, is characterized in that, in described transverse distribution beam design with installation steps, transverse distribution beam is become with vertical joint group by dismounting beam crossbeam, lateral, wherein:

Described dismounting beam crossbeam is made up of biplate dismounting Liang Dan purlin, and dismounting Liang Dan purlin is arranged in pier stud both sides, is supported on wing bracket, arranges lateral between its end face and bottom surface, and its side arranges vertical connection.

Described lateral and vertical connection all adopt angle steel to make, and are connected with dismounting Liang Dan purlin bolt.

Above-mentioned construction method, is characterized in that, in the assembled step of described dismounting beam, first smooth assembled place, puts sleeper as temporary support platform according to dismounting beam chord member nodal pitch, it is drawn main truss center line straight to control; Hand fit's tower crane carries out assembled, first spells lower chord node metal plate, bottom lateral bracing, more assembled brace, adopts tower crane to assist assembled upper chord, vertical rod, last assembled lateral connection rod member and top bracing; Described rod member all adopts assembled to direction, both sides from centre.

Above-mentioned construction method, is characterized in that, in described dismounting beam hoisted in position step:

1) dismounting beam promotes: often across installing two assembly and disassembly beams under box girder web, before every assembly and disassembly beam lifting, first removes two ends 2m upper chord, detains to reduce beam length by the web member of limit; Each assembly and disassembly beam adopts Dun Ding to promote gantry and first rises to installation end chord member directly over transverse distribution beam center, then falls beam on transverse distribution beam, then traversing in place to box girder web; Dismounting beam controls according to immediately below box girder web relative to the position straight line case beam of crossbeam, and curved box girder controls according to dividing middle arrow method equally.

2) dismounting beam is traversing: traversing dismounting beam adopts guide chain to draw in place, must move at dismounting beam two ends before traversing rightabout crossbeam termination vertically drop-down one wire rope to the pre-buried suspension ring in cushion cap top.

3) deformation monitoring at gantry is promoted: adopt instrument to carry out deformation monitoring to lifting gantry in dismounting beam lifting lifting process, hoisting frame length travel should be less than 1% of hoisting frame height, is no more than 5cm.

4) prestressed system: adopt 3t hoist engine traction enhancement prestress stent, prestressed support and fining twisted steel below the dismounting beam set up; Under each dismounting beam, two prestress stents, two groups of fining twisted steels are installed; Often organize fining twisted steel and be divided into oblique fining twisted steel and horizontal fining twisted steel; Dismounting beam end is fixed in oblique fining twisted steel one end, and prestress stent lower end is fixed in one end, and prestress stent lower end is all fixed at horizontal fining twisted steel two ends; Only to oblique fining twisted steel Shi Hanzhang during construction.

5) sandbox is installed: adopt two jack by dismounting beam end jack-up after the girder pre-stressed system installation of dismounting, install sandbox in transverse distribution back portion; Sandbox is installed needs logical sand-passing amount strictly to control dismounting depth of beam, and the sandbox amount of sinking controls according to 1cm; Increase between dismounting beam and sandbox and pad wedge-shaped steel plate.

6) after dismounting beam installation in position, dismounting boom support laterally lays 60cm spacing, and 12 meters long I16 i iron, lay bed die above i iron, before construction case beam, carry out pre-pressing bracket.

Above-mentioned construction method, it is characterized in that, in described box girder construction step, case beam side adopts longitudinal sliding motion formula steel model, only need low latitude once assembled shaping, concrete placings completes one across rear, can along the longitudinal sliding motion of track piecemeal to next hole across in place, slides to adopt the dilatory or crowbar of hoist engine to prize mode to move; Reserved Luo Liang hole before box girder webs, preformed hole arranges 12, and wherein top board arranges 8, and base plate arranges 4.

Above-mentioned construction method, is characterized in that, described dismounting boom support is removed step and carried out after box girder tensioning mud jacking completes, and comprises the following steps:

1) support prestress system is removed: dismounting beam prestressing system unloaded after prestressed concrete box girder stretch-draw completes, remove, beam is separated with bed die; Adopt punching jack to be put by prestressing force essence bundle screw-thread steel to open, remove essence and prick screw-thread steel, finally remove prestress stent.

2) fall and remove sandbox: that opens eight sandboxes rushes down sand hole, utilizing sandbox synchronously to fall to making dismounting beam evenly to decline and depart from certain altitude with bed die; Fall girder apparatus is installed, utilizes the jack of fall girder apparatus lifting dismounting beam and sandbox to depart from, remove sandbox, and dismounting beam is fallen within crossbeam.

3) install beam system: first remove i iron distribution beam and template on the chord member of dismounting beam two ends; Install shoulder pole, essence pricks screw-thread steel, install beam jack; Below dismounting beam upper chord, shoulder pole girder is installed, utilizes essence to prick screw-thread steel and dismounting beam is connected with fall above case beam beam shoulder pole and jack; Adopt φ 17.5 wire rope to intersect at each tie point place after lower shoulder pole girder is connected with dismounting beam and tighten up binding 6 road.

4) hold component to remove: shoulder pole girder in the jack jacking of case top surface of the beam fall girder apparatus, prick screw-thread steel by essence and drive dismounting beam to promote; Stop promoting after dismounting beam support is separated with crossbeam, will cast anchor and screw; Manual demolition end bar members, upper end of thread web member.

5) fall beam: first by lower ground tackle, dismounting beam is hung on case top surface of the beam, screws on anchor on when being connected tight when casting anchor with beam body, and jack jacking makes shoulder pole girder and upper ground tackle closely meet place, and lower ground tackle is separated with bottom pad plate; On screw off ground tackle after, jack oil return drives upper shoulder pole girder, finish rolling deformed bar and dismounting beam to fall, as stated above repeatedly operation until dismounting beam drops down onto ground; The beam process that falls eight jack synchronously fall beam; Finally remove fall girder apparatus.

6) transverse distribution beam and wing bracket is removed: adopt 4 20T jacks to be promoted by crossbeam and depart from wing bracket, and adopt steel wire hang on case beam; Hang operating personnel hanging basket in pier top-hung, the essence of removing wing bracket pricks screw-thread steel pull bar, utilizes the beam preformed hole that to fall at the bottom of beam to hang tackle pulley and transfers bracket and traverse beam to ground; Transverse distribution beam is transferred to ground again by assembly pulley and 2 8T hoist engine entirety.

From such scheme, external prestressing dismounting beam method is applied in the height pier sharp radius curve in-situ beam casting of mountain area by the present invention first, the hoisting method of strutting system structure, support and the frame method that falls are innovated, be proven, compared with existing construction method, the present invention has following advantages:

1, construction method dismounting beam of the present invention has the features such as few, the on-the-spot spelling of part kind is convenient, span compliance is large, strength and stiffness are large.

2, the applying of construction method external prestressing of the present invention effectively improves the rigidity of dismounting beam, successful of putting more energy into.

3, construction method supporting structure of the present invention is simple, clearly stressed, installs, uses, dismantles safe and simple, solve the technical barrier that sharp radius curve beam uses Construction Through Form on Traveler difficulty, can ensure construction main quality.

4, the support integral hoisting of construction method exploitation of the present invention, the facility of dismounting whereabouts and process matched therewith, safe and reliable, easy and simple to handle.

5, construction method of the present invention adapts to the girder of different spans, width and form of structure, does not limit by landform.

6, construction method construction of the present invention is simple, easy to operate, and speed of application is fast, saves the duration, cost-saving.

Accompanying drawing explanation

fig. 1for supporting structure of the present invention is illustrated figure;

fig. 2for lifting gantry of the present invention construction sequence side elevation diagrammeaning figure;

fig. 3for the positive facade of lifting gantry construction sequence of the present invention diagrammeaning figure;

fig. 4for dismounting lifting construction step signal of the present invention figure;

fig. 5for fall girder apparatus structural representation of the present invention figure.

Detailed description of the invention

The technological means realized for making the present invention, creation characteristic, reach object and effect is easy to understand, below in conjunction with fig. 1extremely fig. 4the concrete implementation step of the present invention is described in detail as follows:

1, dismounting boom support structure design

(1) dismounting boom support structure design

Dismounting boom support length is divided into 37.44m, 36.72m, 36m, 34.72m, 34m five kinds of length.Often be made up of two assembly and disassembly beams across support, adopt wing bracket two assembly and disassembly beams to be supported in the temporary support position of pier side, frame upper lays distribution beam, and then assembled formwork is constructed continuous box girder by cross.Support is divided into support system (wing bracket) and strutting system (dismounting beam, small pre-stress system, transverse distribution beam, sandbox).Designing points is that structural strength, rigidity and stability meet construction requirement, and simultaneously support installing, use, dismounting is safe and simple.

(2) dismounting beam column part composition

Dismounting beam, also known as assembled truss beam, is a kind of provisional removable deck type trusses filled rushed to repair of railway being repaiied for bridge during bridge war preparedness or controls flood, general figure" special bridge 0153 " is used in centralized procurement.Basic purlin formula is the magnificent human relations purlin formula of band vertical rod, purlin height 2.5m, internode 2m, main truss center to center distance 2m, span can be entered by 2m mono-and convert abnormal zero span by 0.72m, main rod member is made up of channel-section steel, sheet material, angle steel, and chord member forms I-shaped interface by two groove shape parts, is provided with bottom lateral bracing and sway bracing between main truss.

The main rod member of dismounting beam that the present invention adopts is A3 steel, and rod member connected mode is bolt and peg two kinds of methods.The burnished bolt that job site connects and peg adopt No. 5 steel.The part that spelling uses has 42 kinds, and wherein main rod member has 13 kinds.Splicing structure adopts deck type fish-bellied type structure.The main chord member cross section composition system of truss by two length 4m [30a, [30c or [part of 30c with one deck or two-layered steel plates 300 × 14 side metal plate and two length 2m [30c part forms.Two parts are I-shaped back to being combined in couples, and the spaced apart 32mm of two back ofs the body is so that the thick node metal plate of two pieces of 16mm can be inserted at Nodes in rod member two ends.The web member of trusses is by 2 [30a or 2 [I-shaped cross-section that 30c forms or the T sections that 2 ∠ 100 × 100 × 12 form, the vertical rod of truss is made up of 2 ∠ 100 × 100 × 8, but 3 ∠ 200 × 120 × 16 are then all used in end vertical rod, and wherein two angle steel are located at the outside of beam to connect back timber.The upper bottom lateral bracing of truss and each pole of horizontal-associate and brace are single angle steel, and the upper rack posts of horizontal-associate adopts channel-section steel to cut the reinforced with the longitudinal stability strengthening truss of weldering.

(3) dismounting girder construction strengthens design

After dismounting beam is spelled, at dismounting beam lower chord Nodes, two groups of prestress stents are installed, each prestress stent has two vertical rods, vertical rod adopts two 32a channel-section steel weldable steel batten plates of make-up to make, bridging is set to connect as overall between vertical rod, 8 preformed holes are established in vertical rod lower end, for anchoring prestress muscle.

Between dismounting beam both ends and prestress stent, respectively establish the 8 oblique presstressed reinforcing steels in road, one end of oblique presstressed reinforcing steel is anchored in dismounting beam and winds up end, and one end is anchored in prestress stent lower end.Between two prestress stents, establish the 8 horizontal presstressed reinforcing steels in road, horizontal presstressed reinforcing steel two ends are anchored in prestress stent lower end.

By applying small pre-stress to oblique presstressed reinforcing steel, make dismounting beam form a small amount of antiarch upwards, in order to offset the amount of deflection that the deadweight of dismounting beam produces, simultaneously for arranging camber, carry out construction regulation and control and create condition, there is structure simple, the feature of successful of putting more energy into.

2, preparation:

(1) select correct position as rod member stacking, assembled place at the scene, rod member number class is stacked.

(2) during substructure construction, the relevant built-in fitting of reply carries out pre-buried, stays simultaneously and establishes relevant reserving hole channel.Six φ 32 round steel suspension ring are respectively buried underground, as the lower anchor point of Hanging Basket, cable rope, fairlead, hoist engine etc. in Dun Ding and cushion cap corner and middle position, long limit.Pre-buried six the φ 32 round steel suspension ring in position directly over pier cap end face midline position and bracket, as uses such as guiding, liftings.At pier stud lateral location reserved 10 brackets, reserving hole is installed, bottom rail spreader beam 11 is placed in 2 holes below, 8 holes are used for penetrating bracket pull bar 14 above, prevent reserving hole place concrete pressurized from producing stress and concentrate, adopt pre-embedded steel slab, set up main muscle, encrypt the measures such as stirrup.

(3) laying moves dismounting beam slideway in length and breadth: arrange in the side of Bridge Pier and vertically move dismounting beam slideway, slideway forms: lower berth sleeper, above puts 50 rail twice, spacing two meters.

(4) before dismounting beam lifting construction, all need to process in advance the connecting rod and stressed member that match, under comprising bracket, wear beam, bracket, pull bar, scissors strut, the flat longitudinal strut of crossbeam, sandbox etc.

3, lifting gantry 1 is designed and is installed:

Lifting gantry 1 adopts the military pier of finished product equipment eight or three formula assembled, is divided into pedestal 3, column 4, draw-beam 5, horizontal brace and diagonal brace 6, pole 7, crampon 8, hanging beam 9, and each component all adopts tower crane or small-sized gin pole to be promoted to Dun Ding to complete assembled.

During pier stud construction, at pier top embedded U-shaped bolt 2.Pedestal 3 divides two-layer crisscross assembled by five eight or three pier 2# iron components, is arranged in the groove of pier top, is connected and fixed by embedded U-shaped bolt 2 and bridge pier, adopts the special high-strength bolt of eight or three pier to connect between each component of pedestal 3.

Column 4 is made up of four eight or three pier 1# iron components, is installed on pedestal 3, arranges angle steel horizontal brace and diagonal brace 6 between each vertical member of column 4, be connected with column 4 bolt, to increase rigidity and resistance to overturning according to longitudinal pitch 175cm, horizontal spacing 150cm.

Two 7 meters long draw-beams 5 are longitudinally installed in column 4 top, every root draw-beam 5 by eight or three pier 1#, 2#, 3# iron components divide three layers assembled, angle steel horizontal brace and diagonal brace 6 are set between two draw-beams 5, twice φ 220 steel pipe pole 7 is established, to increase gantry integral rigidity and stability between column 4 root and draw-beam 5 end.

Hanging beam 9 is installed on the end face at lifting girder 5 two ends, and hanging beam 9 adopts two back-to-back 32a channel-section steels to make.Crampon 8 adopts the special high-strength bolt of eight or three pier to be connected to and promotes on gantry hanging beam 9.

4, wing bracket 10 designs and installs:

A pier stud 15 establishes two cover wing brackets 10, and each component of bracket mainly adopts lifting gantry 1 to install.A set of wing bracket 10 is positioned at the flange plate type bracket 12 of pier both sides by two bottom rail spreader beams 11, four, bracket connects support 13, eight bracket pull bars 14 and forms.

Bottom rail spreader beam 11 is the brace summer of flange plate type bracket 12, upper load is passed to pier stud, each pier stud 15 arranges two bottom rail spreader beams 11, every root bottom rail spreader beam 11 adopts two reinforced 40c channel-section steels to be combined into box-structure, longitudinally through pier stud 15 preformed hole, and be welded and fixed with the pre-embedded steel slab 16 in preformed hole, each 400mm of two ends protruded length.After bottom rail spreader beam 11 installation in position, with high grade epoxy resin mortar by preformed hole jam-pack, carry needs to meet bottom rail spreader beam 11.

Two panels flange plate type bracket 12 is respectively established in each pier stud 15 both sides, be supported on bottom rail spreader beam 11, each flange plate type bracket 12 is made up of five pieces of curtain plates and three pieces of central layers, central layer adopts the trapezoidal steel plate composition box-structure of spacing 90mm, thick 30mm, the each cross section of periphery is welded with the steel plate (i.e. curtain plate) of five pieces of wide 300mm, thick 30mm, two pieces of vertical curtain plates respectively arrange 4 φ 40mm preformed holes, for installing bracket pull bar 14.

Between 2 flange plate type brackets 12 of pier stud 15 homonymy, arrange connection support 13 fixed, connect support 13 and all adopt angle steel to make, with the curtain plate bolt of flange plate type bracket 12;

Bracket pull bar 14 adopts φ 32 fining twisted steel of rank 835Mpa, longitudinally through pier stud 15 and wing plates on two sides formula bracket 12 thereof, both are fixed.

5, transverse distribution beam 17 is installed

Transverse distribution beam 17 is made up of dismounting beam crossbeam 18, lateral 19 and vertical 20, and adopt the component lifting of 1 point, lifting gantry, hand fit is assembled.

Dismounting beam crossbeam 18 is made up of biplate dismounting Liang Dan purlin, and dismounting Liang Dan purlin is arranged in pier stud both sides, is supported on wing bracket, arranges lateral 19 between its end face and bottom surface, and its side arranges vertical 20, makes a whole crossbeam Cheng Laiyi entirety.Lateral 19 and vertical 20 all adopts angle steel to make, and is connected with dismounting Liang Dan purlin bolt, strengthens crossbeam resistance to overturning.

Establish bearing beam 22 between transverse distribution beam and wing bracket, bearing beam adopts two long 40c channel-section steels of 6m and two pieces of 10mm steel plate installed-weldeds to form, and side arranges reinforcement steel plate, gains in strength.

6, dismounting beam 21 is assembled:

Below bridge location, utilize tower crane to lift rod member assembled dismounting beam, assembled complete after utilize slideway, by flat vertical shift, dismounting beam is moved to bridge under lift by crane position.

(1) smooth assembled place: the general 5-6m in assembled place is wide, 45m is long, then levelling and smooth is carried out on ground, if place is in slope, guarantee that original place upper thread is an inclined-plane.

(2) sleeper is put as temporary support platform: lay according to dismounting beam chord member nodal pitch, every node location lays two lumps of wood, and laying length is dismounting beam length.On sleeper, dismounting beam center line is drawn in advance straight to control after putting completion.

(3) on time drawn in advance assembled drawing, by the various spare and accessory parts of tower crane handling to platform both sides.

(4) integral assembling: the first step spells lower chord node metal plate, bottom lateral bracing, the assembled vertical rod of second step, brace, then assists assembled upper chord, upper flat bar etc. with tower crane, and all rod members all adopt assembled to direction, both sides from centre.During handling rod member, must arrange and slip rope on rod member, hold rod member by simple and easy hook, swing back and forth after preventing rod member from slinging and when putting off excessive hurting sb.'s feelings.

7, dismounting beam hoisted in position:

The lifting of dismounting beam adopts a set of Lift-on/Lift-off System of the composition such as hoist engine, lifting gantry 1, tackle pulley 25, guide device 26, guide chain 27.

1) hoist engine is in place: fill totally four, the hoist engine hung, wherein two 10t hoist engines 23 (Rong Shengliang >=400m) are arranged on case top surface of the beam of constructing, and two 5t hoist engines 24 are arranged on ground.

2) dismounting beam ground is in place: dismounting beam, by moving dismounting beam slideway in length and breadth, moves to Hoisting Position from assembled place.Vertical shift adopts two, 5t hoist engine, tackle pulley two cover to hold in the palm straining beam body.Traversing consideration adopts jack, and the method for the lower berth lumps of wood is constructed.

3) suspender is installed: dismounting beam 21, after ground enters Hoisting Position, dismounting beam 21 and gantry suspension hook 8 installs tackle pulley 25, and tackle pulley 25 adopts 4 skating cars of 50t, adopts two 10t hoist engines 23 to draw.

4) dismounting beam 21 promotes: often across installing two assembly and disassembly beams 21 under box girder web, before every assembly and disassembly beam 21 lifts, first removes two ends 2m upper chord, detains to reduce beam length by the web member of limit; Each assembly and disassembly beam 21 adopts Dun Ding to promote gantry 1 and first rises to installation end chord member directly over transverse distribution beam 17 center, then falls beam on transverse distribution beam 17, then traversing in place to box girder web; Dismounting beam 21 controls according to immediately below box girder web relative to the position straight line case beam of crossbeam 17, and curved box girder controls according to dividing middle arrow method equally.

3) dismounting beam 21 is traversing: it is in place that traversing dismounting beam 21 adopts guide chain to draw, must move at dismounting beam 21 two ends before traversing rightabout crossbeam termination vertically drop-down one wire rope to cushion cap top pre-buried suspension ring 28, the maximum pull that traversing dismounting beam 21 rear wire rope in place bears is 3.5 tons.

4) deformation monitoring at gantry 1 is promoted: dismounting beam 21 lifts in lifting process and adopts instrument to carry out deformation monitoring to lifting gantry 1, and hoisting frame length travel should be less than 1% of hoisting frame height, is no more than 5cm.

5) prestressed system: adopt 3t hoist engine 29 traction enhancement prestress stent 30, prestressed support 30 and fining twisted steel 31 below the dismounting beam 21 set up; Each dismounting beam installs two prestress stents, 30, two groups of fining twisted steels 31 21 times; Often organize fining twisted steel 31 and be divided into oblique fining twisted steel 32 and horizontal fining twisted steel 33; Dismounting beam 21 end is fixed in oblique fining twisted steel 32 one end, and prestress stent 30 lower end is fixed in one end, and prestress stent 30 lower end is all fixed at horizontal fining twisted steel 33 two ends; Only to oblique fining twisted steel 32 Shi Hanzhang during construction.

6) sandbox 33 is installed: adopt two jack 34 by dismounting beam 21 end jack-up after the installation of dismounting beam 21 prestress system, install sandbox 33 at transverse distribution beam 17 top; Sandbox 33 is installed needs logical sand-passing amount strictly to control dismounting depth of beam, and sandbox 33 amount of sinking controls according to 1cm; Increase between dismounting beam 21 and sandbox 33 and pad wedge-shaped steel plate 35, guarantee dismounting boom support and sandbox 33 stable connection, contact good.

7), after dismounting beam 21 installation in position, dismounting beam 21 is laterally laid 60cm spacing, the I16 i iron 36 of 12 meters long, above i iron 36, lays bed die 37, then carry out pre-pressing bracket.

8, pre-pressing bracket:

Prepressing materials is packed gravel, and precompressed mode is equal-load preloading, and precompressed weight is 1.1 times of the deadweight of case beam, and precompressed order is tunneling boring place Min layers pressure, and namely one deck repaves lower one deck after being paved with.Loading procedure establishes special messenger to command, special messenger department claims, special messenger counts, and strict control load distribution, stops 30min after being often paved with one deck, uses the deformation of timbering situation of precision level to observation point place to observe.Once, m-deformation curve during drafting, measures final settlement after distortion convergence in whole loading observation in complete every 4 hours, calculates support shell-shaped deformation value Δ bullet; After precompressed is complete, evenly unload, when vertical bed die according to observing the sedimentation value Δ bullet adjustment bed die camber obtained.

9, case beam 38 is constructed:

Case beam 38 construction process is: end web reinforcement and steel strand → installation internal mold → installation roof steel bar and steel strand → cast box beam concrete → health etc. are installed → installed to bed die laying → side form, and strong → stretch-draw mud jacking → health → mono-section box girder has been constructed.

Reserved Luo Liang hole 39 before box girder webs, preformed hole 39 arranges 12, and wherein top board arranges 8, and base plate arranges 4.

10, dismounting boom support is removed

Dismounting boom support is removed and is carried out after case beam 37 stretch-draw mud jacking completes, and comprises the following steps:

1) support prestress system is removed: dismounting beam 21 prestressing system unloaded after prestressed concrete box girder 37 stretch-draw completes, remove, beam is separated with bed die; Adopt punching jack 40 to be put by oblique prestressing force essence bundle screw-thread steel 32 to open, remove essence and prick screw-thread steel 31, finally dismounting prestress stent 30.

2) fall and remove sandbox 33: that opens eight sandboxes 33 rushes down sand hole, evenly decline and bed die 37 depart from certain altitude to utilize sandbox 33 synchronously to fall to making dismounting beam 21; Installation fall girder apparatus 41, utilizes the jack 42 of fall girder apparatus 41 to promote dismounting beam and sandbox 33 departs from, and removes sandbox 33, and is fallen within transverse distribution beam 17 by dismounting beam 21.

3) fall girder apparatus 41 is installed: the i iron 36 first on the chord member of removal dismounting beam 21 two ends and the template of case beam 38; Install four beam jack 42 that fall in case beam 38 two ends end face symmetry, the upper shoulder pole 43 of every two jack 42 placed on top one, upper shoulder pole 43 two ends respectively penetrate an essence and prick screw-thread steel 44, and essence is pricked screw-thread steel 44 upper end and adopted upper ground tackle 45 to be fixed on shoulder pole 43; Shoulder pole girder 48 under installing below dismounting beam 21 upper chord, pricks screw-thread steel 44 lower end with essence and adopts double nut 49 to fix; Adopt φ 17.5 wire rope to intersect at each tie point place after lower shoulder pole girder 48 is connected with dismounting beam 21 and tighten up binding 6 road, as safeguard procedures.

4) hold component to remove: shoulder pole girder 43 in jack 42 jacking of case beam 38 end face fall girder apparatus 41, prick screw-thread steel 44 by essence and drive dismounting beam 21 to promote; Stop promoting after dismounting beam 21 bearing is separated with transverse distribution beam 17, lower ground tackle 46 is screwed, make case beam 38 directly bear dismounting beam 21 weight; Manual demolition end bar members, upper end of thread web member, guarantees that beam body falls accessible.

5) fall beam: the operating principle of the beam that falls be utilize the jacking repeatedly of jack 42, fall after rise progressively transfer dismounting beam 21.First be rotated down lower ground tackle 46, make billet 50 close contact on itself and top surface of the beam, prick screw-thread steel 44 by lower ground tackle 469 and essence and dismounting beam 21 is hung on case beam 38 end face; Rotate up the distance of the about jack stroke of ground tackle 45, jack 42 is shoulder pole girder 43 in jacking slowly, until with upper ground tackle 45 close contact, lower ground tackle 46 is separated with billet 50; Rotate up the distance that lower ground tackle 46 is greater than a jack stroke, jack 42 oil return drives upper shoulder pole girder 43, finish rolling deformed bar 44 and dismounting beam 21 to fall, and repeatedly operates until dismounting beam 21 drops down onto ground as stated above; Finally remove fall girder apparatus 41.The beam process that falls eight jack 42 synchronously fall beam, guarantee that fining twisted steel 44 vertically falls.When height of drop is larger, fining twisted steel 44 adopts connector 47 spreading.

6) remove transverse distribution beam 17 and wing bracket 10: adopt 4 20T jacks 51 to be promoted by transverse distribution beam 17 and depart from wing bracket 10, adopt steel wire hang on case beam 38; Hang operating personnel hanging basket in pier top-hung, the essence of removing wing bracket 10 pricks screw-thread steel pull bar 14, utilizes the beam preformed hole 39 that to fall at the bottom of beam to hang tackle pulley 52 and transfers wing bracket 10 and bottom rail spreader beam 11 to ground; Transverse distribution beam 17 to ground is transferred again by assembly pulley 52 and 2 8T hoist engine 53 entirety.

The present invention has that rigidity is large, intensity is high, materials'use amount is little, it is simple and easy to install, speed of application soon, not by the feature such as landform, landforms restriction, solve the technical barrier that sharp radius curve beam uses mobile formwork difficulty.By Shi Hanzhang on dismounting beam, improve dismounting beam integral rigidity, strengthen dismounting beam span compliance.It is large that self-control promotes gantry rigidity, easy for installation, has good landform compliance and flexibility, effectively can ensure the safety of dismounting beam integral hoisting.The facility that the high-altitude support overall pulling down that the present invention adopts falls and process matched therewith, safe and reliable, easy and simple to handle, solve dress and hang difficulty of construction that is highly too low, that fall to steadily not bringing.Instant invention overcomes the impact of high pier, complicated topographical conditions, society, economy, energy-saving benefit are remarkable, and simple to operate, have highly application value.

Embodiment recited above is only be described the preferred embodiment of the present invention; not scope of the present invention is limited; do not departing under the present invention designs spiritual prerequisite; the various distortion that the common engineers and technicians in this area make technical solution of the present invention and improvement, all should fall in protection domain that claims of the present invention determine.

Claims (8)

1., for a dismounting boom support construction method for high pier sharp radius curve cast-in-situ box girder, it is characterized in that, this construction method comprises the following steps:

(1) design of lifting gantry and installation, lifting gantry adopts the military pier of finished product equipment eight or three formula assembled, is arranged in pier coping portion groove;

(2) wing bracket design and installation, wing bracket mainly adopts lifting gantry to install, described wing bracket to be connected by two bottom rail spreader beams, four flange plate type brackets being positioned at pier both sides, bracket by a set of wing bracket support, eight bracket pull bars form;

(3) design of transverse distribution beam and installation, transverse distribution beam is become with vertical joint group by dismounting beam crossbeam, lateral;

(4) dismounting beam is assembled, and first smooth assembled place, puts sleeper as temporary support platform according to dismounting beam chord member nodal pitch, it is drawn main truss center line straight to control;

(5) dismounting beam hoisted in position, comprises that dismounting beam promotes, dismounting beam is traversing, promotes the deformation monitoring at gantry, prestressed system, sandbox install, lay i iron;

(6) pre-pressing bracket;

(7) box girder construction, case beam side adopts longitudinal sliding motion formula steel model, and only need low latitude once assembled shaping, concrete placings completes one across rear, can along the longitudinal sliding motion of track piecemeal to next hole across in place, slides to adopt the dilatory or crowbar of hoist engine to prize mode to move;

(8) dismounting boom support is removed, comprise support prestress system remove, falls and remove sandbox, install beam system, end component dismounting, the beam that falls, dismounting transverse distribution beam and wing bracket.

2. construction method according to claim 1, is characterized in that, in the design of described lifting gantry with installation steps, lifting gantry adopts the military pier of finished product equipment eight or three formula assembled, is arranged in pier coping portion groove; Pedestal adopts two-layer 5 crisscross formations of eight or three pier 2# iron, is connected and fixed by embedded U-shaped bolt and bridge pier; Column adopts four 1# iron to be fixed on pedestal by longitudinal 175cm, horizontal 150cm spacing; 7 meters long three layers of draw-beam are installed at column top; Different model diagonal brace rod member is adopted to be fixed between column and between draw-beam; Crampon is installed on lifting main beam member, adopts the special high-strength bolt of eight or three pier to be connected to and promotes Gantry top surface of the beam end; Pole together with respectively arranging with arm termination at column root, adopts 10T hoist engine traction 4 and 50 tons of tackle pulley liftings during lifting; Described lifting gantry adopts small-sized gin pole lifting member to complete assembled to Dun Ding, is mainly used in erection & lift wing bracket, transverse distribution beam, sandbox, assembled good dismounting beam.

3. construction method according to claim 2, it is characterized in that, in described wing bracket design with installation steps, described wing bracket mainly adopts lifting gantry to install, described wing bracket to be connected by two bottom rail spreader beams, four flange plate type brackets being positioned at pier both sides, bracket by a set of wing bracket support, eight bracket pull bars form, wherein:

Described bottom rail spreader beam is the brace summer of flange plate type bracket, upper load is passed to pier stud, each pier stud arranges two bottom rail spreader beams, every root bottom rail spreader beam adopts two reinforced 40c channel-section steels to be combined into box-structure, longitudinally through pier stud preformed hole, and be welded and fixed with the pre-embedded steel slab in preformed hole, each 400mm of two ends protruded length;

Described flange plate type bracket is made up of 5 pieces of curtain plates and 3 pieces of central layers, central layer adopts the trapezoidal steel plate composition box-structure of spacing 90mm, thick 30mm, the Plate Welding of each cross section of periphery and five pieces of wide 300mm, thick 30mm, two pieces of vertical curtain plates is respectively arranged 4 φ 40mm preformed holes;

Described bracket connects support and comprises transverse horizontal support and oblique bridging, arrange between 2 wing plate brackets of bridge pier homonymy one bridging and together with horizontal brace fixed, connect and support all employing angle steel making, with the curtain plate bolt of flange plate type bracket;

Described bracket pull bar adopts φ 32 fining twisted steel of rank 835Mpa, longitudinally through pier stud and wing plates on two sides formula bracket thereof, both are fixed.

4. construction method according to claim 1, is characterized in that, in described transverse distribution beam design with installation steps, transverse distribution beam is become with vertical joint group by dismounting beam crossbeam, lateral, wherein:

Described dismounting beam crossbeam is made up of biplate dismounting Liang Dan purlin, and dismounting Liang Dan purlin is arranged in pier stud both sides, is supported on wing bracket, arranges lateral between its end face and bottom surface, and its side arranges vertical connection.

Described lateral and vertical connection all adopt angle steel to make, and are connected with dismounting Liang Dan purlin bolt.

5. construction method according to claim 1, is characterized in that, in the assembled step of described dismounting beam, first smooth assembled place, puts sleeper as temporary support platform according to dismounting beam chord member nodal pitch, it is drawn main truss center line straight to control; Hand fit's tower crane carries out assembled, first spells lower chord node metal plate, bottom lateral bracing, more assembled brace, adopts tower crane to assist assembled upper chord, vertical rod, last assembled lateral connection rod member and top bracing; Described rod member all adopts assembled to direction, both sides from centre.

6. construction method according to claim 1, is characterized in that, in described dismounting beam hoisted in position step:

1) dismounting beam promotes: often across installing two assembly and disassembly beams under box girder web, before every assembly and disassembly beam lifting, first removes two ends 2m upper chord, detains to reduce beam length by the web member of limit; Each assembly and disassembly beam adopts Dun Ding to promote gantry and first rises to installation end chord member directly over transverse distribution beam center, then falls beam on transverse distribution beam, then traversing in place to box girder web; Dismounting beam controls according to immediately below box girder web relative to the position straight line case beam of crossbeam, and curved box girder controls according to dividing middle arrow method equally.

2) dismounting beam is traversing: traversing dismounting beam adopts guide chain to draw in place, must move at dismounting beam two ends before traversing rightabout crossbeam termination vertically drop-down one wire rope to the pre-buried suspension ring in cushion cap top.

3) deformation monitoring at gantry is promoted: adopt instrument to carry out deformation monitoring to lifting gantry in dismounting beam lifting lifting process, hoisting frame length travel should be less than 1% of hoisting frame height, is no more than 5cm.

4) prestressed system: adopt 3t hoist engine traction enhancement prestress stent, prestressed support and fining twisted steel below the dismounting beam set up; Under each dismounting beam, two prestress stents, two groups of fining twisted steels are installed; Often organize fining twisted steel and be divided into oblique fining twisted steel and horizontal fining twisted steel; Dismounting beam end is fixed in oblique fining twisted steel one end, and prestress stent lower end is fixed in one end, and prestress stent lower end is all fixed at horizontal fining twisted steel two ends; Only to oblique fining twisted steel Shi Hanzhang during construction.

5) sandbox is installed: adopt two jack by dismounting beam end jack-up after the girder pre-stressed system installation of dismounting, install sandbox in transverse distribution back portion; Sandbox is installed needs logical sand-passing amount strictly to control dismounting depth of beam, and the sandbox amount of sinking controls according to 1cm; Increase between dismounting beam and sandbox and pad wedge-shaped steel plate.

6) after dismounting beam installation in position, dismounting boom support laterally lays 60cm spacing, and 12 meters long I16 i iron, lay bed die above i iron, before construction case beam, carry out pre-pressing bracket.

7. construction method according to claim 1, it is characterized in that, in described box girder construction step, case beam side adopts longitudinal sliding motion formula steel model, only need low latitude once assembled shaping, concrete placings completes one across rear, can along the longitudinal sliding motion of track piecemeal to next hole across in place, slides to adopt the dilatory or crowbar of hoist engine to prize mode to move; Reserved Luo Liang hole before box girder webs, preformed hole arranges 12, and wherein top board arranges 8, and base plate arranges 4.

8. construction method according to claim 1, is characterized in that, described dismounting boom support is removed step and carried out after box girder tensioning mud jacking completes, and comprises the following steps:

1) support prestress system is removed: dismounting beam prestressing system unloaded after prestressed concrete box girder stretch-draw completes, remove, beam is separated with bed die; Adopt punching jack to be put by prestressing force essence bundle screw-thread steel to open, remove essence and prick screw-thread steel, finally remove prestress stent.

2) fall and remove sandbox: that opens eight sandboxes rushes down sand hole, utilizing sandbox synchronously to fall to making dismounting beam evenly to decline and depart from certain altitude with bed die; Fall girder apparatus is installed, utilizes the jack of fall girder apparatus lifting dismounting beam and sandbox to depart from, remove sandbox, and dismounting beam is fallen within crossbeam.

3) install beam system: first remove i iron distribution beam and template on the chord member of dismounting beam two ends; Install shoulder pole, essence pricks screw-thread steel, install beam jack; Below dismounting beam upper chord, shoulder pole girder is installed, utilizes essence to prick screw-thread steel and dismounting beam is connected with fall above case beam beam shoulder pole and jack; Adopt φ 17.5 wire rope to intersect at each tie point place after lower shoulder pole girder is connected with dismounting beam and tighten up binding 6 road.

4) hold component to remove: shoulder pole girder in the jack jacking of case top surface of the beam fall girder apparatus, prick screw-thread steel by essence and drive dismounting beam to promote; Stop promoting after dismounting beam support is separated with crossbeam, will cast anchor and screw; Manual demolition end bar members, upper end of thread web member.

5) fall beam: first by lower ground tackle, dismounting beam is hung on case top surface of the beam, screws on anchor on when being connected tight when casting anchor with beam body, and jack jacking makes shoulder pole girder and upper ground tackle closely meet place, and lower ground tackle is separated with bottom pad plate; On screw off ground tackle after, jack oil return drives upper shoulder pole girder, finish rolling deformed bar and dismounting beam to fall, as stated above repeatedly operation until dismounting beam drops down onto ground; The beam process that falls eight jack synchronously fall beam; Finally remove fall girder apparatus.

6) transverse distribution beam and wing bracket is removed: adopt 4 20T jacks to be promoted by crossbeam and depart from wing bracket, and adopt steel wire hang on case beam; Hang operating personnel hanging basket in pier top-hung, the essence of removing wing bracket pricks screw-thread steel pull bar, utilizes the beam preformed hole that to fall at the bottom of beam to hang tackle pulley and transfers bracket and traverse beam to ground; Transverse distribution beam is transferred to ground again by assembly pulley and 2 8T hoist engine entirety.