Construction method and system for conversion of immersed tube prefabricated top plate steel bar system
Technical Field
The invention relates to the field of immersed tube tunnel construction. More particularly, the invention relates to a construction method and a system for conversion of a immersed tube prefabricated roof steel bar system.
Background
The immersed tube tunnel is used as a structure for crossing the river across the sea, and can be used for tunnel construction in relatively weak foundation conditions, earthquake active areas, inland and marine environments, urban areas with limited operation and environment sensitive areas. At present, immersed tube prefabrication mainly comprises layered prefabrication and full-section prefabrication, and the full-section prefabrication method gradually becomes a preferred method for immersed tube prefabrication due to the advantages of small quantity of construction joints, low water seepage risk and the like. According to the immersed tube prefabricating process, the construction of the top plate steel bar has great influence on the full-section prefabricating construction period.
At present, in immersed tube full-section prefabrication construction, top plate steel bars are bound mainly by an internal mold trolley or a steel bar trolley. Roof steel bars are bound by means of an internal mold trolley, the binding is carried out only after the last section of concrete reaches the stripping strength, the internal mold is demoulded in place, the roof steel bar plates occupy key lines, the construction efficiency is slow, and the construction period is severely limited; the sink pipe of the HongZhu Australian bridge adopts an industrial section matching prefabrication method, a large number of sliding systems are arranged in a factory, reinforcing steel bars of a bottom plate, a side wall and a top plate are bound according to sections in a partitioning mode, adjacent sections of the sink pipe are of semi-rigid structures, longitudinal main reinforcements are disconnected and not connected, and a reinforcing cage slides after the sections are bound. And (4) binding the top plate steel bars by using a steel bar platform, then sliding the whole steel bar cage to a concrete pouring area, and then carrying out system conversion. For the immersed tube full-section prefabrication project of longitudinal main reinforcement full-length connection among the segments, the prefabrication pedestals are all provided with sliding systems, the cost is too high, and the quality of adjacent segment steel bar joints cannot be guaranteed after the steel bar cage is pushed and slid, so that the industrialized segment matching prefabrication construction process cannot meet the requirements.
Disclosure of Invention
The invention aims to provide a construction method for conversion of a immersed tube prefabricated top plate steel bar system, and solves the problem of construction of immersed tube full-section prefabricated top plate steel bars.
To achieve these objects and other advantages in accordance with the purpose of the invention, there is provided a construction method for conversion of a steel reinforcement system for a sinking pipe precast roof, comprising the steps of:
step 1, construction before demoulding of segment n external mold
Step 1.1, after the segment n +1 bottom plate steel bars and the vertical wall steel bars are bound, installing a middle pipe gallery supporting framework, wherein the root of the middle pipe gallery supporting framework is connected with the mid-partition wall framework, and the central line of the supporting framework coincides with the central line of the immersed tube.
Step 1.2, disassembling the steel bar trolley at the n-position of the segment, adjusting the steel bar trolley to a demoulding state, and moving the steel bar trolley to the n +1 position of the segment where the bottom plate steel bars and the vertical wall steel bars are bound to be in place for binding the top plate steel bars;
step 1.3, hanging a plurality of rows of chain blocks below a top truss of the external mold trolley with the poured segment n;
step 1.4, hanging a plurality of hanging beams below each row of chain blocks, connecting the hanging beams, and adjusting the chain blocks to be horizontal to the hanging beams;
step 2, segment n +1 top plate system conversion construction
2.1, after the top plate steel bars of the section n +1 are bound, adjusting an outer mold trolley at the section n to a demolding state, driving to a reinforcement cage of the section n +1, and hanging a steel wire rope binding and fastening device at the lower part of each hanging beam;
2.2, connecting the reinforcement cage with the hanging beam by using a steel wire rope to ensure that the hanging beam holds force;
step 2.3, adjusting the gallery trolley at the segment n to a demoulding state, and driving to the reinforcement cage at the segment n + 1;
2.4, moving out the segment n +1 reinforcement cage after the segment n +1 reinforcement trolley is separated from the reinforcement cage;
2.5, when the steel bar trolley at the segment n +1 moves out of the segment n +1, adjusting the internal mold trolley at the segment n to a contraction state, and simultaneously moving the steel bar trolley into the steel bar cage at the segment n +1 for measurement and positioning;
step 3, segment n +1 die assembly construction
Step 3.1, removing the steel wire rope and the steel wire rope binding and fastening device, and lifting the hanging beam to the highest point;
and 3.2, mounting an end die, and fixedly connecting the end die with the inner die and the outer die to carry out die assembly.
Preferably, the steel bar trolley, the internal mold trolley and the pipe gallery trolley are of a hydraulic walking structure.
Preferably, the steel wire rope binding and fastening device is a turn buckle.
Preferably, the step 1.2 is specifically: after the segment n +1 bottom plate and the vertical wall steel bars are bound, disassembling a support screw rod of the steel bar trolley at the segment n, contracting a support oil cylinder of the steel bar trolley, and adjusting to a demoulding state; moving the steel bar trolley to a segment n +1, completely landing a movable supporting leg and a fixed supporting leg of the steel bar trolley, debugging the steel bar trolley, feeding oil to a supporting oil cylinder, measuring and positioning, and increasing the elevation of the top surface of the steel bar trolley in advance of design so as to enable the elevation of the transformed steel bar cage system to be consistent with the design;
after the steel bar trolley is in place, a support screw rod of the steel bar trolley is fastened, top plate steel bars of the sections n +1 are bound, longitudinal main bars of the sections n +1 are connected with exposed steel bars of the sections n, high-strength cushion blocks are supported at the bottoms of the top plate steel bars and bound with the steel bars firmly, and binding of the top plate steel bars of the sections n +1 is completed before outer molds of the sections n are modified and demolded.
Preferably, a strength type framework is arranged in the top plate steel bar, and the longitudinal distance of the strength type framework is consistent with the distance of lifting lugs at the bottom of the hanging beam.
Preferably, the step 2.3 is specifically: disassembling a support screw rod of the gallery trolley, withdrawing a support oil cylinder and a jacking oil cylinder of the gallery trolley for demoulding, and enabling a fixed supporting leg and a movable supporting leg of the gallery trolley to enter a steel reinforcement cage of the segment n +1 by a mutual leg-falling method; after the gallery trolley is in place, the movable supporting leg and the fixed supporting leg of the gallery trolley are completely landed, the supporting oil cylinder and the jacking oil cylinder of the gallery trolley are used for supplying oil, the measurement and debugging are carried out, and the supporting screw rod of the gallery trolley is fastened, so that the gallery trolley is attached to the high-strength cushion block of the supporting cushion at the bottom of the top plate steel bar.
Preferably, the step 2.4 is specifically: the supporting screw rod of the steel bar trolley at the segment n +1 position is disassembled, the supporting oil cylinder and the jacking oil cylinder of the steel bar trolley slowly return oil, after the top surface of the steel bar trolley is separated from the steel bar cage, the oil return is stopped, whether the hanging beam, the chain block, the steel wire rope binding and fastening device, the steel bar cage and the outer die truss are deformed or damaged is checked, after the check is qualified, the supporting oil cylinder and the jacking oil cylinder of the steel bar trolley continue to return oil, the steel bar trolley is completely separated, and the steel bar trolley is driven out of the segment n +1 steel bar.
The invention also provides a construction system for conversion of the immersed tube prefabricated roof steel bar system, which comprises the following components: the system comprises an outer die trolley, an inner die trolley, a gallery trolley, a steel bar trolley and a lifting appliance for system conversion;
the inner mould trolley, the gallery trolley and the steel bar trolley are pushed by respective hydraulic systems and walk in a mutually leg-falling mode through respective fixed supporting legs and movable supporting legs, and the inner mould trolley, the gallery trolley and the steel bar trolley are respectively provided with a self-retractable supporting oil cylinder and a self-retractable supporting screw rod;
the outer mold trolley comprises an outer mold top layer truss, a track and a traveling mechanism; the tracks are arranged on two sides of the immersed tube, the walking mechanism drives the outer mold trolley to walk, and the outer mold top layer truss is provided with lifting points;
the lifting appliance comprises a lifting beam for distributing stress of the reinforcement cage, a chain block for adjusting the height of the lifting beam, a steel wire rope binding and fastening device for connecting the lifting beam and the reinforcement cage and a steel wire rope;
the top of hanging beam has laid a plurality of top lugs, and its position of laying is unanimous with external mold top layer truss hoisting point, a plurality of bottom lugs have been laid to the bottom of hanging beam equidistant, top lug and bottom lug both sides all are provided with the stiffening plate.
The invention at least comprises the following beneficial effects:
1. adopt reinforcing bar platform truck ligature roof reinforcing bar in advance, through the system conversion, reduced key line work, effectively shortened key line engineering time, guaranteed immersed tube full section construction and adjacent section vertical main muscle lead to long the connection, improved construction quality, reduced immersed tube infiltration risk.
2. The prefabricated time of a single immersed tube standard segment is greatly shortened, the template trolley and the steel bar trolley can be used in a circulating sequence, the installation and the operation are convenient, the working efficiency is high, the construction period is shortened, and the cost is obviously reduced.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
FIG. 1 is a flow chart of the construction method for conversion of the immersed tube precast roof slab steel bar system of the present invention;
FIG. 2 is a schematic view of the construction system for conversion of the immersed tube precast roof slab steel bar system of the present invention;
FIG. 3 is a schematic view of a spreader of the present invention;
FIG. 4 is a schematic longitudinal sectional view of step 1 in example 1 of the present invention;
FIG. 5 is a schematic cross-sectional view of step 1 in example 1 of the present invention;
FIG. 6 is a schematic longitudinal sectional view of step 2 in example 1 of the present invention;
FIG. 7 is a schematic cross-sectional view of step 2 in example 1 of the present invention;
FIG. 8 is a schematic cross-sectional view of step 3 in example 1 of the present invention.
The device comprises a 1-outer die trolley, a 2-inner die trolley, a 3-gallery trolley, a 4-steel bar trolley, a 5-lifting appliance, a 6-lifting beam, a 6.1-double-spliced channel steel, a 6.2-top lifting lug, a 6.3-bottom lifting lug, a 6.4-stiffening plate, a 7-chain block, an 8-basket bolt, a 9-steel wire rope, a 10-fixed supporting leg, a 11-movable supporting leg, a 12-supporting oil cylinder, a 13-supporting screw rod, a 14-lifting oil cylinder, a 15-rail, a 16-walking mechanism, a 17-outer die top layer truss, an 18-middle pipe gallery supporting framework, a 19-middle partition wall framework, a 20-strength framework and a 21-end die.
Detailed Description
The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.
In the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
Example 1
As shown in fig. 1, the invention provides a construction method for conversion of a immersed tube precast roof steel bar system, in this embodiment, the steel bar trolley 4, the internal mold trolley 2 and the pipe gallery trolley are hydraulic walking structures, and can be self-telescopic and self-walking.
The method comprises the following steps:
step 1, as shown in fig. 4 and 5, construction content before demolding of segment n external mold
Step 1.1, segment n +1 bottom plate reinforcing bar and vertical wall reinforcement, after bottom plate reinforcing bar and vertical wall reinforcement accomplish, gallery supporting framework 18 in the installation, gallery supporting framework 18 adopts the shaped steel preparation, and the root of gallery supporting framework 18 and mid-partition wall skeleton 19 weld, just the supporting framework central line coincides with immersed tube central line.
Step 1.2, after the bottom plate of the section n +1 and the vertical wall steel bars are bound, disassembling a support screw rod 13 of the steel bar trolley 4 at the section n, contracting a support oil cylinder 12 of the steel bar trolley 4, and adjusting to a demoulding state; moving the reinforcement trolley 4 to a section n +1, completely landing the movable supporting leg 11 and the fixed supporting leg 10 of the reinforcement trolley 4, debugging the reinforcement trolley 4, feeding oil to the supporting oil cylinder 12, measuring and positioning, wherein the elevation of the top surface of the reinforcement trolley 4 is increased compared with the design due to the flexible structure of the reinforcement cage, so that the elevation of the reinforcement cage system after conversion is consistent with the design;
4 backs to the position of reinforcing bar platform truck, fastening reinforcing bar platform truck 4's support lead screw 13, the roof reinforcing bar of segment n +1 begins to ligature, and expose the bar connection with the vertical main muscle of segment n +1 and segment n, roof reinforcing bar bottom props up the high strength cushion, and it is firm with the reinforcement, set up strength type skeleton 20 in the roof reinforcing bar, the bulk rigidity when guaranteeing the steel reinforcement cage hoist and mount, strength type skeleton 20 vertical interval is unanimous with 6.3 intervals of 6 bottom lugs of hanging beam, and segment n +1 roof reinforcing bar ligature must be accomplished before the drawing of patterns is revised to the n external mold of segment.
Step 1.3, hanging a plurality of rows of chain blocks 7 below a top truss of the external mold trolley 1 with the poured segment n;
step 1.4, hanging a plurality of hanging beams 6 below each row of chain block 7, connecting the single rows of hanging beams 6 by welding or bolts, and adjusting the chain block 7 to be horizontal to the hanging beams 6;
step 2, as shown in fig. 6 and 7, converting construction of the segment n +1 top plate system
2.1, after the top plate steel bars of the section n +1 are bound, adjusting the outer mold trolley 1 at the section n to a demolding state, driving to a reinforcement cage of the section n +1, and suspending a turn buckle 8 at the lower part of each hanging beam 6;
2.2, connecting the turn buckle 8 with a strength type framework 20 by using a steel wire rope 9 to realize the connection of the reinforcement cage and the hanging beam 6, so that the hanging beam 6 holds force;
step 2.3, disassembling a support screw 13 of the gallery trolley 3 at the segment n, withdrawing a support oil cylinder 12 and a jacking oil cylinder 14 of the gallery trolley 3, and demoulding, wherein a fixed supporting leg 10 and a movable supporting leg 11 of the gallery trolley 3 enter a reinforcement cage of the segment n +1 by a mutual leg-falling method; after the gallery trolley 3 is in place, the movable supporting leg 11 and the fixed supporting leg 10 of the gallery trolley 3 all fall to the ground, the supporting oil cylinder 12 and the jacking oil cylinder 14 of the gallery trolley 3 deliver oil, the oil is measured and debugged, and the supporting screw rod 13 of the gallery trolley 3 is fastened, so that the gallery trolley 3 is attached to the high-strength cushion block of the top plate reinforcing steel bar bottom support pad.
And 2.4, disassembling a support screw rod 13 of the steel bar trolley 4 at the section n +1, slowly returning oil to a support oil cylinder 12 and a jacking oil cylinder 14 of the steel bar trolley 4, stopping oil returning after the top surface of the steel bar trolley 4 is separated from a steel bar cage, checking whether a hanging beam 6, a chain block 7 and a steel wire rope 9 binding and fastening device, the steel bar cage and an outer die truss are deformed or damaged, continuously returning oil to the support oil cylinder 12 and the jacking oil cylinder 14 of the steel bar trolley 4 after the check is qualified, and completely separating the steel bar trolley 4 to drive out of the section n +1 steel bar cage.
Step 2.5, when the steel bar trolley 4 of the segment n +1 is driven out of the segment n +1, the inner mould trolley 2 of the segment n is adjusted to a contraction state, and meanwhile, the steel bar trolley moves into a steel bar cage of the segment n +1, and measurement and positioning are carried out;
step 3, as shown in FIG. 8, the segment n +1 is constructed by die assembly
Step 3.1, removing the steel wire rope 9 and the steel wire rope 9 binding and fastening device, and lifting the hanging beam 6 to the highest point;
and 3.2, mounting the end die 21, and fixedly connecting the end die with the inner die and the outer die to carry out die assembly.
In the embodiment, the steel bar trolley 4 is used for binding the top plate steel bars in advance, so that the top plate steel bars and the concrete pouring and curing of the adjacent sections are synchronously performed, and the binding of the top plate steel bars is completed before the outer mold of the adjacent sections is demolded; then the external mold is moved into a reinforcement cage, and the top plate reinforcement cage is suspended through a top truss and a special lifting appliance 5 of the external mold trolley 1; and then demoulding the steel bar trolley 4 to move out of the steel bar cage, synchronously moving the steel bar cage into the internal mould trolley 2, realizing system conversion, and finally carrying out mould closing work. The immersed tube top plate steel bars are bound and optimized after the inner die is closed, and then the binding is completed before the outer die is released, so that the purposes of positioning the inner die, binding the top plate steel bars, optimizing the die closing into conversion of a top plate steel bar system and closing the die are realized, and the steel bar trolley 4 is used for binding the top plate steel bars before the outer die is released, so that key circuits are not occupied, the key circuit procedures are reduced, the construction time of the key circuits and the top plate steel bars is effectively shortened, the full-section construction of the immersed tube is ensured, the longitudinal main bars of adjacent sections are connected in a full-length mode, the construction quality is; meanwhile, the template trolley and the steel bar trolley 4 can be used in a circulating sequence, the installation and the operation are convenient, the deformation of the steel bar cage is small, the working efficiency is higher, the prefabrication time of a single immersed tube is greatly shortened, and the cost is obviously reduced.
Example 2
A construction system for conversion of a immersed tube precast top plate rebar system, as shown in fig. 2 and 3, comprising: the system comprises an outer die trolley 1, an inner die trolley 2, a gallery trolley 3, a steel bar trolley 4 and a lifting appliance 5 for system conversion;
centre form platform truck 2, corridor platform truck 3 and reinforcing bar platform truck 4 all adopt walking mode, push away through respective hydraulic system promptly, walk through the mode of respective fixed leg 10 and the mutual leg of falling of activity landing leg 11, centre form platform truck 2, corridor platform truck 3 and reinforcing bar platform truck 4 all are provided with the support cylinder 12 that can contract by oneself and the support lead screw 13 that can contract by oneself.
Wherein the mode walking of the mutual leg of fixed landing leg 10 and activity landing leg 11 is taken as an example to interior mode platform truck 2, specifically is: 1. lifting the cylinders of the movable supporting legs 11 by using the cylinders of the movable supporting legs 11, stressing the movable supporting legs 11, unloading the fixed supporting legs 10, retracting the supporting leg rods of the fixed supporting legs 10, and retracting the cylinders of the fixed supporting legs 10 to enable the bottom surfaces of the fixed supporting legs 10 to be higher than the upper surfaces of the poured inner mold bottom plates; 2. operating the walking oil cylinder to enable the inner mould trolley 2 and the inner mould to integrally walk forwards to a preset position; 3. the oil cylinders of the fixed supporting legs 10 lift the cylinders to enable the fixed supporting legs 10 to bear force, the movable supporting legs 11 unload, and the oil cylinders of the movable supporting legs 11 retract the cylinders to enable the bottom surfaces of the movable supporting legs 11 to be higher than the upper surfaces of the poured inner mold bottom plates; 4. operating the walking oil cylinder to enable the movable supporting leg 11 to move forwards to a preset position; and 5, repeating the steps, enabling the whole internal mold trolley 2 and the whole template to walk in place, and adjusting the fixed supporting legs 10 and the internal mold oil cylinder to finish the mold erecting work of the template.
The external mold trolley 1 comprises an external mold top truss 17, a track 15 and a traveling mechanism 16; the tracks 15 are arranged on two sides of the immersed tube, the walking mechanism 16 drives the outer mold trolley 1 to walk on the tracks 15, the walking mechanism 16 drives the outer mold trolley 1 to walk by adopting a motor, and the outer mold top layer truss 17 is provided with lifting points;
the lifting appliance 5 comprises a lifting beam 6 for distributing stress of the reinforcement cage, a chain block 7 for adjusting the height of the lifting beam 6, a steel wire rope 9 binding and fastening device (specifically, a turn buckle 8) for connecting the lifting beam 6 and the reinforcement cage, and a steel wire rope 9; the hanging beam 6 is made of double-spliced channel steel 6.1.
The top of the hanging beam 6 is provided with a plurality of top lifting lugs 6.2, the arrangement position of the top lifting lugs is consistent with the hanging point of the outer die top layer truss 17, the bottom of the hanging beam 6 is provided with a plurality of bottom lifting lugs 6.3 at equal intervals, and two sides of each of the top lifting lugs 6.2 and the bottom lifting lugs 6.3 are provided with stiffening plates 6.4.
While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.