CN-121992734-A - Continuous beam closure section box inner formwork support-free system and construction method

CN121992734ACN 121992734 ACN121992734 ACN 121992734ACN-121992734-A

Abstract

The invention discloses a support-frame-free system for a template in a closure section box of a continuous beam and a construction method, and belongs to the technical field of bridge engineering construction. Aiming at the problems of low construction efficiency and large space interference of a full framing in a traditional closure section box, the invention provides a combined type integral frame scheme. The system comprises a hanging basket structure and a combined template which are positioned outside a beam body, and a n-shaped frame without a supporting frame which is arranged in the box. The two side beam bodies form a temporary whole through rigid locking, and the U-shaped frame is connected with the beam bodies and the outer side templates through opposite-pull fixing structures to form a space stress whole, so that a self-balancing template system is formed, and the independent upright post support in the box is canceled. The method realizes the rapid assembly and disassembly of the template, thoroughly avoids the interference of the support, the steel bars and the pipelines, and remarkably improves the construction efficiency and quality of the closure section.

Inventors

Ren Qiuji
LI HUIPENG
WANG ZHANDONG
SU JIAYU
SUN WENQI
ZHANG YULONG
QI GANG
CHEN YONGHUA
ZHU GANG
LU YONGKUAN
REN GUODONG
WANG CHANGHAO
WU ZHIFEI
ZHANG JIANCHUAN

Assignees

中交一公局第八工程有限公司

Dates

Publication Date: 20260508
Application Date: 20260401

Claims (10)

1. The non-support frame system of the box inner template of the closure section of the continuous beam comprises a hanging basket structure arranged on the outer side of the continuous beam and a combined template (10) arranged on the hanging basket structure, and is characterized in that the box inner of the continuous beam is also provided with a n-shaped non-support frame system which is connected into a whole through a opposite-pull fixing structure, and the system comprises an inner top plate structure (1), an upper chamfer structure (2), a web plate structure (3) and a lower chamfer structure (4); a rigid locking structure (5) is arranged between the beam bodies at the two sides of the closure section; The hanging basket structure comprises a hoisting structure (7) anchored at the top of the beam body, and the hoisting structure (7) is connected with a bottom plate (9) horizontally arranged at the bottom of the beam body through a suspender structure (8); Each structure in the n-shaped non-support frame system is connected with the beam body, the bottom plate (9) or the combined template (10) through a pull-up fixing structure and realizes multidirectional limiting, so that the n-shaped non-support frame system, the hanging basket structure and the combined template (10) form a self-balancing template stress structure which depends on the beam bodies at two sides.
2. The continuous beam closure section in-box formwork support-free system of claim 1, wherein the inner roof structure (1) comprises a first panel (11), a first secondary beam (12) and a first main beam (13) which are sequentially arranged from inside to outside, and the end part of the first main beam (13) is anchored with the beam body through a first opposite-pulling fixing structure (14).
3. The system of no support frame for the continuous beam closure section in-box formwork of claim 1, wherein the upper chamfering structure (2) comprises a second panel (21), a second secondary beam (22), an auxiliary beam (23) and a second main beam which are sequentially arranged from inside to outside, and the end part of the second main beam is anchored with the beam body through a second opposite-pulling fixing structure.
4. The continuous beam closure section in-box formwork support-free system of claim 1, wherein the web structure (3) comprises a panel III (31), a secondary beam III (32) and a primary beam III (33) which are sequentially arranged from inside to outside, and the primary beam III (33) is connected with the combined formwork (10) through a counter-pulling fixing structure III (34).
5. The system of support-free continuous beam closure section in-box formworks of claim 1, characterized in that the panels of the lower chamfer structure (4) are fixed to the beam body by means of a counter-pull fixing structure or rigid support.
6. The continuous beam closure section in-box formwork support-free system of claim 2,3 or 4, wherein the first (13), second and third (33) girders are double-spliced channel steel or double-spliced steel pipes.
7. The continuous beam closure section in-box formwork support-less system of claim 1, wherein the tie-down securing structure comprises a tie-bar (141) and a nut (142) threaded at an end of the tie-bar (141).
8. The system of no support frame for the continuous beam closure section in-box formwork according to claim 1, wherein the rigid locking structure (5) comprises profile steel symmetrically arranged along the axial direction of the beam body, and two ends of the profile steel are welded and fixed with embedded parts embedded in the beam body.
9. A continuous beam closure segment construction method based on the system of any one of claims 1-8, comprising the steps of: 1) Removing the inner guide beam and the inner side template of the hanging basket, removing the rear anchor of the hanging basket after the hanging basket is moved to the construction position of the closure section, and removing the inner guide beam and the original inner side template of the hanging basket, wherein only the web outer side template, the bottom plate template and the hanging basket main body structure are reserved, and the hanging basket comprises a hoisting structure (7), a suspender structure (8) and a bottom plate (9); 2) The method comprises the steps of adjusting elevation according to an outer side basket hanging system, binding bottom plate steel bars and web plate steel bars, supervising and accepting, adjusting and fixing elevation, linearity and verticality of a joint member Duan Moban by depending on a web plate outer side template and a bottom plate template in the outer side basket hanging system, installing the bottom plate steel bars and the web plate steel bars in a template enclosing space after adjustment, synchronously completing the positioning of a prestressed pipeline, checking and accepting on site by a supervising engineer after the steel bars are bound, and entering the next step after the steel bars are qualified; 3) The method comprises the steps of installing a reverse U-shaped support-free frame system of an inner template of a continuous beam, sequentially installing a lower chamfer structure (4), a web plate structure (3), an upper chamfer structure (2) and an inner roof plate structure (1) in a closure section box, respectively connecting and fixing a first opposite-pull fixing structure (14), a second opposite-pull fixing structure (34) and a fourth opposite-pull fixing structure (6) with a beam body and a combined template (10), applying pretightening force to each opposite-pull fixing structure, and realizing multidirectional limiting of the template system in horizontal, vertical and space directions so as to enable the inner template system and the outer template system and the two side beam bodies to form a self-balancing stress structure, wherein the step does not need any independent support in the box, and is a core implementation link of the technical scheme of the invention; 4) After the installation of the support frame-free system is completed, installing a rigid locking structure (5) at the embedded parts of the two side beam bodies of the closure section to form a temporary rigid connection structure, and matching the rigid locking structure with a temporary prestress beam when necessary to enhance the overall rigidity of the locking structure and ensure that the cantilever beam bodies at the two sides have the capacity of jointly bearing the newly-increased load during the construction period; 5) Pouring concrete and completing closure, pouring closure sections in the sequence of a bottom plate, a web plate and a top plate in a template enclosing space after rigid locking is completed, transferring the load of the newly poured concrete to beam bodies on two sides through a combined template (10), a opposite-pulling fixing structure and a rigid locking structure (5) in the pouring process, and removing a template system and the rigid locking structure after the strength of the concrete meets the design requirement, so that the closure sections are converted into a permanent stress state from a construction stress state, and continuous beam closure is completed.
10. The construction method according to claim 9, wherein in the step (4), concrete pouring is performed in the order of the bottom plate, the web plate and the top plate, and the whole construction process is independent of any independent column type temporary support system arranged in the box to bear the concrete pouring load.

Description

Continuous beam closure section box inner formwork support-free system and construction method Technical Field The invention relates to the technical field of bridge engineering construction, in particular to a continuous beam closure section box inner template support-free system and a construction method. Background In the cantilever pouring construction of a continuous beam bridge, the closure section is a key part for connecting adjacent cantilever sections and realizing the conversion of a structural system. Because the two side beams do not form a continuous stress system during closure construction, construction loads such as the dead weight of a template, the dead weight of concrete and the like generated by casting of the concrete in the closure section must be borne by reliable temporary measures. At present, the technical scheme is that a full-hall scaffold or a densely arranged section steel supporting system is erected in a closure section box. However, this conventional support has the following inherent drawbacks: The construction efficiency is low, the number of supporting rods is large due to the narrow cavity and the complex shape of the part in the box, the installation procedure is complicated, the space positioning and adjustment are difficult, the later dismantling is time-consuming and labor-consuming, and the overall construction progress is severely restricted. The space interference is serious, namely, the dense support rods and the pre-arranged reinforcement cage and the pre-stressed pipeline are easy to generate position conflict in the limited space. The method not only affects the precision and the efficiency of steel bar binding and pipeline positioning, but also is often forced to perform on-site cutting and avoidance adjustment of the support rod piece, and further reduces construction controllability and structural quality. The system has poor integrity, the traditional support is arranged in a dot type or a distributed type, the whole stress with uniform space is difficult to form, the control difficulty of the whole rigidity and the stability of the template system is high, and the deformation control in the concrete pouring process is unfavorable. Therefore, a need exists for a novel formwork support system that can significantly reduce the number of support bars in the box, achieve rapid installation and removal, and fundamentally avoid spatial interference with the rebar and prestressed pipe, so as to improve the industrialization, standardization level and overall efficiency of closure segment construction. Disclosure of Invention The invention aims to overcome the defects of low construction efficiency, large space interference and poor system integrity of the support in the closure section box in the prior art, and provides a continuous beam closure section box template support-free system and a construction method. The system aims to replace scattered supports by constructing a combined type integral stress frame, realize quick assembly and disassembly and accurate positioning of the template, thoroughly eliminate interference with an internal steel bar pipeline, and further achieve the purposes of improving construction efficiency and guaranteeing engineering quality and safety. In order to achieve the above purpose, the present invention adopts the following technical scheme: A template support-free system in a continuous beam closure section box is characterized in that a combined integral stress frame is constructed. The system consists of an outside system and an inside system: The outside system comprises a hanging basket structure arranged by using the existing cantilever construction equipment (such as hanging basket) and a standardized combined template. The inner system is a U-shaped frame without supporting frame arranged in the box. The frame is formed by splicing an inner top plate structure, an upper chamfer structure, a web plate structure and a lower chamfer structure through a preset opposite-pull fixing structure, so that a space rigid frame matched with the outline of a box chamber is formed. And connecting and locking, namely mutually tying the inner side system and the outer side system through a opposite-pulling fixing structure, and firmly anchoring the inner side system and the poured beam body. Meanwhile, two side beams are temporarily connected into a whole through a rigid locking structure at two ends of the closure section. A construction method of a formwork support-free system in a continuous beam closure section box comprises the steps of enabling beam bodies on two sides of a closure section to form a temporary integral structure through a rigid locking structure before closure construction, arranging a combined formwork, an inner roof plate structure, an upper chamfer structure, a web plate structure and a lower chamfer structure on a reinforcement cage section between the two side beam bodies, enabling the formwork system to form a