CN115058987A - Performance improving method for existing precast hollow slab bridge and precast hollow slab bridge - Google Patents

Performance improving method for existing precast hollow slab bridge and precast hollow slab bridge Download PDF

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Publication number
CN115058987A
CN115058987A CN202210832577.3A CN202210832577A CN115058987A CN 115058987 A CN115058987 A CN 115058987A CN 202210832577 A CN202210832577 A CN 202210832577A CN 115058987 A CN115058987 A CN 115058987A
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Prior art keywords
bridge
hollow slab
concrete
existing
slab bridge
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CN202210832577.3A
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刘宇闻
陈维
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Wisdri Engineering and Research Incorporation Ltd
Wisdri Urban Construction Engineering Technology Co Ltd
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Wisdri Engineering and Research Incorporation Ltd
Wisdri Urban Construction Engineering Technology Co Ltd
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Priority to CN202210832577.3A priority Critical patent/CN115058987A/en
Publication of CN115058987A publication Critical patent/CN115058987A/en
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    • E—FIXED CONSTRUCTIONS
    • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
    • E01D22/00—Methods or apparatus for repairing or strengthening existing bridges ; Methods or apparatus for dismantling bridges
    • E—FIXED CONSTRUCTIONS
    • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
    • E01D19/00—Structural or constructional details of bridges
    • E01D19/12—Grating or flooring for bridges; Fastening railway sleepers or tracks to bridges
    • E01D19/125—Grating or flooring for bridges
    • E—FIXED CONSTRUCTIONS
    • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
    • E01D2/00—Bridges characterised by the cross-section of their bearing spanning structure
    • E—FIXED CONSTRUCTIONS
    • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
    • E01D2101/00—Material constitution of bridges
    • E01D2101/20—Concrete, stone or stone-like material
    • E01D2101/24—Concrete
    • E01D2101/26—Concrete reinforced

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Bridges Or Land Bridges (AREA)

Abstract

The invention discloses a performance improving method of an existing precast hollow slab bridge and the precast hollow slab bridge, wherein a hinge joint (1) at a bridge bottom plate (3) is cleaned, concrete roughening or steel bar planting is carried out on the bridge bottom plate (3), a cast-in-place layer and pavement (2) are broken, concrete in the hinge joint (1) is cleaned to form a grouting hole (11), when the outer space of the bridge is enough, a support (10) is arranged on the bridge floor close to an anti-collision guardrail, the support (10) crosses the anti-collision guardrail and extends out of the bridge floor, a suspender (5) is arranged at the end part of the bridge floor, when the outer space of the bridge is not enough, a hole is drilled at the root part of a cantilever (12) on the bridge floor and penetrates through the suspender (5), a bottom die block of a template (6) is in supporting connection with the suspenders (5) at two sides, and a side die is in laminating connection with a bridge web plate at the side where the template is located through an anchor bolt (9); concrete is injected into the grouting holes (11), and the post-cast concrete and the beam body are connected into a whole to bear force together. The invention improves the longitudinal and transverse stress performance of the existing structure and avoids the erection of a bracket under a bridge.

Description

Performance improving method for existing precast hollow slab bridge and precast hollow slab bridge
Technical Field
The invention belongs to the field of bridge construction, and particularly relates to a performance improving method for an existing precast hollow slab bridge and the existing precast hollow slab bridge.
Background
The prefabricated hollow slab bridge is adopted in most of middle and small-span roads and urban bridges with spans of 13-20 m, and the prefabricated hollow slab bridge is poor in structural durability due to excessive pursuit of economic indexes and neglected of structural details and self-resistance reserve during design, so that the prefabricated hollow slab bridge brings about a plurality of problems to normal traffic: the prefabricated hollow slab bridge has more diseases in the operation process, particularly weak links are easily formed at the hinge joint, and the diseases such as cracking, water seepage, crack-pointing concrete falling, bridge deck longitudinal cracks and the like are easily caused; bridge deck rainwater seeps along the hinge joint between the plates for a long time, so that saltpetering and even calcification adsorption are easily formed; after the hinge joint falls off, veneer stress is easy to occur on adjacent plates, the transverse integrity is weakened, transverse dislocation is caused, and the support is further hollowed or failed.
At present, for the problem of insufficient bearing capacity of a prefabricated hollow slab bridge, a common reinforcing method of sticking a steel plate and a common reinforcing method of sticking a fiber composite material are not obvious in effect of improving the transverse integrity although the longitudinal stress condition of the structure is improved. For the problem of damage to the hinge joint of the prefabricated hollow slab bridge, secondary pouring is usually adopted, and although the transverse stress condition can be improved in a short time, passive reinforcement is still not obvious to the transverse direction of the reinforced structure in the long run, so that the secondary damage can not be fundamentally avoided.
In the face of the huge number of the precast hollow slab bridges, how to promote the overall stress performance of the existing structure, reduce or even stop various diseases, and prolong the service life of the bridge are problems to be solved urgently in engineering.
Disclosure of Invention
The invention aims to provide a performance improving method of an existing precast hollow slab bridge and the precast hollow slab bridge, which are used for enhancing the integrity of a beam body and post-cast concrete, improving the longitudinal and transverse stress performance of the existing structure and avoiding the erection of a support under a bridge.
The technical scheme adopted by the invention is as follows:
the utility model provides a current precast hollow slab bridge performance promotion method, carries out local processing to the disease position that current precast hollow slab bridge appears, during the processing: chiseling and cleaning the hinge joint (1) at the bridge bottom plate (3), and performing chiseling treatment or bar planting on the concrete of the bridge bottom plate (3) to form a shear connection structure (4); breaking a cast-in-place layer and pavement (2) on the bridge floor, and removing concrete in the hinge joint (1) to form a grouting hole (11); when the external space of the bridge is enough, a support (10) is arranged on the bridge floor close to the anti-collision guardrail, the support (10) crosses over the anti-collision guardrail and extends out of the bridge floor, a suspender (5) is arranged at the end part of the support, and when the external space of the bridge is not enough, a hole is formed in the root part of a cantilever (12) on the bridge floor and penetrates through the suspender (5); laying a template (6), wherein a bottom die of the template (6) is in supporting connection with the suspension rods (5) on two sides, a side die is in attaching connection with a bridge side web plate on the side where the bottom die is located through anchor bolts (9), the template (6) and a bridge bottom plate (3) form a closed space (7), and a reinforcing mesh (8) is arranged in the closed space (7) in advance; after the template (6) is finished, high-strength or ultrahigh-performance concrete is injected into the grouting holes (11) on the bridge floor, and after the closed space (7) and the grouting holes (11) are filled with the concrete, the concrete is cured; and (3) after the maintenance is finished, the post-cast concrete and the beam body are connected into a whole to bear the force jointly, the support (10) and the template (6) are removed, the openings of the positions of the anchor bolts (9) on the hanger rods (5) on the bridge deck and the bridge side web are restored with equal strength, and the cast-in-situ bridge deck layer and the pavement (2) are restored.
Furthermore, the suspension rods (5) are distributed in pairs along two sides of the bridge, and the connecting line of the suspension rods (5) is perpendicular to the central line of the bridge.
Further, the concrete injected into the grouting holes (11) is added with an additive for improving the fluidity and reducing or avoiding vibration.
Further, the height of the closed space (7) is determined by calculation in advance according to the requirement of the bearing capacity of the bridge.
Further, the anchor bolts (9) and the hanging rods (5) are distributed in a staggered mode.
Further, the template (6) adopts a steel template or a wood template.
A precast hollow slab bridge is obtained by adopting the existing precast hollow slab bridge performance improving method.
The invention has the beneficial effects that:
according to the invention, the concrete fills the closed space (7) and the grouting holes (11), the integrity of the beam body and post-cast concrete is enhanced by the shear connection structure (4) and the reinforcing mesh (8), the longitudinal and transverse stress performance of the existing structure is improved, transverse diseases can be effectively improved, the structural integrity is good, and the structural use performance and durability are improved; according to the invention, the support system of the template (6) is arranged by the beam body, so that a support is prevented from being erected under a bridge, the construction is convenient, rapid and efficient, and the support (10) spans the anti-collision guardrail and extends out of the bridge floor, so that the anti-collision guardrail and the bridge floor are prevented from being damaged.
Drawings
FIG. 1 is a schematic view of a bridge floor processing system according to an embodiment of the present invention.
FIG. 2 is a schematic illustration of the processing and laying of forms on a bridge deck in an embodiment of the invention.
Fig. 3 is a schematic view of the installation of the side forms of the formwork and the bridge in the embodiment of the invention.
In the figure: 1-reaming and sewing; 2, laying a cast-in-place layer; 3-a bridge floor; 4-a shear connection structure; 5-a suspender; 6-template; 7-a closed space; 8-reinforcing mesh; 9-anchor bolt; 10-a scaffold; 11-grouting holes; 12-cantilever.
Detailed Description
The invention is further described below with reference to the figures and examples.
The utility model provides a current precast hollow slab bridge performance promotion method, carries out local processing to the disease position that current precast hollow slab bridge appears, if disease such as hinge joint drops, vertical crack, horizontal crack appear, during the processing: as shown in fig. 1, chiseling and cleaning a hinge joint 1 at a bridge bottom plate 3, and performing chiseling treatment or bar planting on concrete of the bridge bottom plate 3 to form a shear connection structure 4; as shown in fig. 2, the cast-in-place layer and the pavement 2 on the bridge deck are broken, and the concrete in the hinge joints 1 is removed to form grouting holes 11; as shown in fig. 2, when the external space of the bridge is enough, a bracket 10 is installed on the bridge floor close to the crash barrier, the bracket 10 extends out of the bridge floor across the crash barrier and is provided with a suspender 5 at the end, and when the external space of the bridge is not enough, a hole is drilled at the root position of a cantilever 12 on the bridge floor and penetrates through the installation suspender 5; as shown in fig. 2 and 3, a template 6 is laid, a bottom die of the template 6 is in supporting connection with the suspenders 5 on two sides, a side die is in attaching connection with a bridge side web plate on the side where the side die is located through anchor bolts 9, the template 6 and a bridge bottom plate 3 form a closed space 7, and a steel mesh 8 is arranged in the closed space 7 in advance; after the template 6 is finished, high-strength or ultrahigh-performance concrete is injected into the grouting holes 11 on the bridge floor, and after the closed space 7 and the grouting holes 11 are filled with the concrete, the concrete is cured; after the maintenance is finished, the post-cast concrete and the beam body are connected into a whole to be stressed together, the support 10 and the template 6 are dismantled, the openings at the positions of the anchor bolts 9 on the hanger rods 5 on the bridge deck and the bridge side web plates are restored with equal strength, and the cast-in-place layer of the bridge deck and the pavement 2 are restored.
In this embodiment, the suspension rods 5 are distributed in pairs along two sides of the bridge, and the connecting line of the suspension rods 5 is perpendicular to the central line of the bridge, so that the stability of the support is improved.
In this embodiment, the concrete poured into the grouting holes 11 is added with an admixture for improving fluidity, reducing or avoiding vibration.
In the present embodiment, the height of the enclosed space 7 is determined by precalculation according to the bridge bearing capacity requirement.
In this embodiment, the anchor bolts 9 and the suspension rods 5 are distributed in a staggered manner to avoid interference.
In the present embodiment, the template 6 is a steel template or a wooden template.
A precast hollow slab bridge is obtained by adopting the existing precast hollow slab bridge performance improving method.
According to the invention, the concrete fills the closed space 7 and the grouting holes 11, the integrity of the beam body and the post-cast concrete is enhanced by the shear connection structure 4 and the reinforcing mesh sheets 8, the longitudinal and transverse stress performance of the existing structure is improved, the transverse damage can be effectively improved, the structural integrity is good, and the structural use performance and durability are improved; according to the invention, the support system of the template 6 is arranged by the beam body, so that a support is prevented from being erected under a bridge, the construction is convenient, rapid and efficient, and the support 10 spans the anti-collision guardrail and extends out of the bridge floor, so that the anti-collision guardrail and the bridge floor are prevented from being damaged.
It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.

Claims (7)

1.一种现有预制空心板桥梁性能提升方法，其特征在于：对现有预制空心板桥梁出现的病害部位进行局部处理，处理时，1. an existing prefabricated hollow slab bridge performance improvement method, is characterized in that: carry out partial treatment to the diseased part that existing prefabricated hollow slab bridge occurs, during processing, 凿除并清理桥梁底板(3)处铰缝(1)，对桥梁底板(3)混凝土进行凿毛处理或植筋从而形成剪力连接结构(4)；破除桥面上的现浇层及铺装(2)，清除铰缝(1)内的混凝土使之形成注浆孔(11)；桥梁外空间足够时，在桥面上靠近防撞护栏位置安装支架(10)，支架(10)跨过防撞护栏伸出桥面并在端部设置吊杆(5)，桥梁外空间不够时，在桥面上悬臂(12)根部位置打孔并穿过安装吊杆(5)；布设模板(6)，模板(6)的底模与两侧的吊杆(5)支撑地连接、侧模通过锚栓(9)与所在侧的桥梁边腹板贴合地连接，模板(6)与桥梁底板(3)形成封闭空间(7)，封闭空间(7)内预先设置钢筋网片(8)；模板(6)完成后，在桥面上向注浆孔(11)注入高强或超高性能混凝土，混凝土填充完封闭空间(7)和注浆孔(11)后，进行混凝土养护；养护完成，后浇混凝土与梁体连接成整体共同受力后，拆除支架(10)、模板(6)，等强恢复桥面上吊杆(5)和桥梁边腹板上锚栓(9)位置的开孔，恢复桥面现浇层及铺装(2)。Chisel and clean the hinge joints (1) at the bridge floor (3), chisel the concrete of the bridge floor (3) or plant reinforcement to form a shear connection structure (4); remove the cast-in-place layer and pavement on the bridge deck Install (2), remove the concrete in the hinge joint (1) to form a grouting hole (11); when the space outside the bridge is sufficient, install the bracket (10) on the bridge deck near the crash barrier, and the bracket (10) spans Extend the bridge deck through the anti-collision guardrail and set hanger rods (5) at the ends. When the space outside the bridge is not enough, punch holes at the root of the cantilever (12) on the bridge deck and pass through the installation hanger rods (5); 6), the bottom form of the formwork (6) is connected to the suspension rods (5) on both sides in a supporting manner, the side formwork is connected to the side web of the bridge on the side through the anchor bolt (9), and the formwork (6) is connected to the bridge. The bottom plate (3) forms a closed space (7), and a steel mesh sheet (8) is preset in the closed space (7); after the template (6) is completed, inject high-strength or ultra-high performance into the grouting hole (11) on the bridge deck Concrete, after the concrete fills the enclosed space (7) and the grouting hole (11), concrete curing is carried out; after the curing is completed, after the post-cast concrete and the beam body are connected to form an integral force, the bracket (10) and the formwork (6) are removed. , restore the openings at the positions of the suspension rods (5) on the bridge deck and the anchor bolts (9) on the side web of the bridge, and restore the cast-in-place layer and pavement (2) of the bridge deck. 2.如权利要求1所述的现有预制空心板桥梁性能提升方法，其特征在于：吊杆(5)沿桥梁两侧成对分布，一对吊杆(5)的连线垂直于桥梁中心线。2. The existing prefabricated hollow slab bridge performance improvement method as claimed in claim 1, characterized in that: the suspension rods (5) are distributed in pairs along both sides of the bridge, and the connecting line of a pair of suspension rods (5) is perpendicular to the center of the bridge Wire. 3.如权利要求1所述的现有预制空心板桥梁性能提升方法，其特征在于：注入注浆孔(11)的混凝土添加有提高流动性、减少或避免振捣的外加剂。3. The existing prefabricated hollow slab bridge performance improvement method according to claim 1, characterized in that: the concrete injected into the grouting hole (11) is added with an admixture to improve fluidity and reduce or avoid vibration. 4.如权利要求1所述的现有预制空心板桥梁性能提升方法，其特征在于：封闭空间(7)的高度根据桥梁承载力要求预先计算确定。4. The existing method for improving the performance of a prefabricated hollow slab bridge according to claim 1, wherein the height of the closed space (7) is pre-calculated and determined according to the bridge bearing capacity requirement. 5.如权利要求1所述的现有预制空心板桥梁性能提升方法，其特征在于：锚栓(9)和吊杆(5)交错分布。5. The existing method for improving the performance of a prefabricated hollow slab bridge according to claim 1, wherein the anchor bolts (9) and the hanger rods (5) are staggered. 6.如权利要求1所述的现有预制空心板桥梁性能提升方法，其特征在于：模板(6)采用钢模板或木模板。6. The existing prefabricated hollow slab bridge performance improvement method according to claim 1, wherein the formwork (6) adopts a steel formwork or a wooden formwork. 7.一种预制空心板桥梁，其特征在于：采用如权利要求1至6任一所述的现有预制空心板桥梁性能提升方法施工得到。7. A prefabricated hollow slab bridge, characterized in that: it is constructed by adopting the existing method for improving the performance of a prefabricated hollow slab bridge according to any one of claims 1 to 6.
CN202210832577.3A 2022-07-14 2022-07-14 Performance improving method for existing precast hollow slab bridge and precast hollow slab bridge Pending CN115058987A (en)

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101644032A (en) * 2009-08-31 2010-02-10 中交通力建设股份有限公司 Beam-removing rib-increasing strengthening construction technology of highway bridge
KR20100034098A (en) * 2008-09-23 2010-04-01 삼표이앤씨 주식회사 Shoe construction method for prefabricated prestressed girder and prefabricated prestressed girder bridge construction method
KR20120134282A (en) * 2011-06-02 2012-12-12 위영민 Slab-type box girder with a vertical connecting structure made by precast concrete and method constructing the bridge thereof
CN209568359U (en) * 2019-01-16 2019-11-01 中交四公局第六工程有限公司 A kind of falsework for the construction of outer-enwraped type Guard fence base
CN112627066A (en) * 2021-01-04 2021-04-09 浙江交工集团股份有限公司 UHPC and slow-bonding steel strand based hollow slab bridge comprehensive reinforcing system and construction method thereof
CN113981839A (en) * 2021-10-22 2022-01-28 中冶南方城市建设工程技术有限公司 Method for reinforcing transverse overall performance of prefabricated hollow slab beam
CN114086483A (en) * 2021-11-16 2022-02-25 武汉理工大学 Longitudinal section steel-UHPC-based prestressed hollow slab lifting and reinforcing method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100034098A (en) * 2008-09-23 2010-04-01 삼표이앤씨 주식회사 Shoe construction method for prefabricated prestressed girder and prefabricated prestressed girder bridge construction method
CN101644032A (en) * 2009-08-31 2010-02-10 中交通力建设股份有限公司 Beam-removing rib-increasing strengthening construction technology of highway bridge
KR20120134282A (en) * 2011-06-02 2012-12-12 위영민 Slab-type box girder with a vertical connecting structure made by precast concrete and method constructing the bridge thereof
CN209568359U (en) * 2019-01-16 2019-11-01 中交四公局第六工程有限公司 A kind of falsework for the construction of outer-enwraped type Guard fence base
CN112627066A (en) * 2021-01-04 2021-04-09 浙江交工集团股份有限公司 UHPC and slow-bonding steel strand based hollow slab bridge comprehensive reinforcing system and construction method thereof
CN113981839A (en) * 2021-10-22 2022-01-28 中冶南方城市建设工程技术有限公司 Method for reinforcing transverse overall performance of prefabricated hollow slab beam
CN114086483A (en) * 2021-11-16 2022-02-25 武汉理工大学 Longitudinal section steel-UHPC-based prestressed hollow slab lifting and reinforcing method

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