CN113463498A

CN113463498A - Structure is prevented subsiding by prefabricated concatenation bridgehead

Info

Publication number: CN113463498A
Application number: CN202010242279.XA
Authority: CN
Inventors: 孔令熙; 马晓刚; 凌宏伟; 陆文亮
Original assignee: Shanghai Pudong Architectural Design & Research Institute Co ltd
Current assignee: Shanghai Pudong Architectural Design & Research Institute Co ltd
Priority date: 2020-03-31
Filing date: 2020-03-31
Publication date: 2021-10-01

Abstract

The invention relates to a prefabricated spliced bridge head anti-settlement structure which comprises an abutment, a pavement structure layer, a butt strap structure layer, a plain concrete layer, a gravel cushion layer, a pile foundation structure and a road base layer. Compared with the prior art, the invention has the advantages of simple construction, economy, environmental protection, convenient replacement and maintenance and the like.

Description

Structure is prevented subsiding by prefabricated concatenation bridgehead

Technical Field

The invention relates to an anti-settlement structure for a bridge head, in particular to an anti-settlement structure for a prefabricated spliced bridge head.

Background

In municipal bridge construction, the road and the bridgehead joint position often can cause the difference of road surface and bridge floor to subside because of the foundation rigidity difference of road bed road surface and bridge structures, influence driving comfort level. Generally, a better compaction process and roadbed filling and bridge head butt strap arrangement are adopted to reduce differential settlement, but the conditions of breakage and the like of the butt strap structure are caused by the fact that the butt strap structure is separated from the roadbed filling due to the problems of foundation settlement, roadbed filling loss, roadbed filling failure to reach the compaction degree and the like.

Chinese patent CN105803922B discloses a high embankment earth-filled bridge head anti-settlement structure, which realizes smooth transition of rigidity between a roadbed and a bridge foundation structure through changes of pile length and pile diameter in pile foundation structure design, thereby solving the problem of vehicle jump at the bridge head. However, the anti-settlement structure in the patent can only be excavated again and the butt strap is poured on site again after the butt strap structure is damaged, so that the maintenance period of the bridge is prolonged, and the influence on road traffic is large.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide the prefabricated spliced bridge head anti-settling structure which is simple in construction, economical and environment-friendly.

The purpose of the invention can be realized by the following technical scheme:

a prefabricated spliced bridge head anti-settlement structure comprises an abutment, a pavement structure layer, a butt strap structure layer, a plain concrete layer, a gravel cushion layer, a pile foundation structure and a road base layer; the pavement structure layer is laid on the butt-strap structure layer; one end of the butt strap structure layer is erected on the abutment; the pile foundation structure is connected with the lap slab structure layer; plain concrete layer and rubble bed course lay between attachment strap structural layer and roadbed in proper order, attachment strap structural layer and pile foundation structure be prefabricated construction, directly will assemble prefabricated attachment strap structural layer and pile foundation structure at the job site to use the fixed pile foundation structure of cast in situ concrete.

Preferably, one end of the butt strap structure layer is hinged with the abutment.

Preferably, the butt strap structure layer comprises a plurality of prefabricated butt straps and plate connecting pieces; the plurality of prefabricated butt straps are connected through plate connecting pieces.

More preferably, a gap is arranged between the prefabricated butt straps, and a water stopping material is filled in the gap; the water stopping material is asphalt mastic.

More preferably, the plate connecting member includes two first connecting blocks, a second connecting block for connecting the two first connecting blocks, and a screw; the two first connecting blocks are respectively arranged on two adjacent prefabricated butt straps; the first connecting block is provided with a first clamping groove matched with the second connecting block; the second connecting block is arranged in the first clamping groove; and two ends of the second connecting block are respectively connected with the first connecting block through screws.

More preferably, the prefabricated butt strap is provided with a second clamping groove matched with the first connecting block.

More preferably, the pile foundation structure comprises a prefabricated pile foundation and a prefabricated cap beam; the prefabricated pile foundation is connected with the prefabricated cap beam through cast-in-place concrete; the prefabricated cap beam is connected with the lap plate structure layer through a plate connecting piece.

More preferably, the precast cap beam comprises a main body beam, a third clamping groove positioned on the main body beam and a through hole for accommodating the precast pile foundation and the cast-in-place concrete; and the third clamping groove is matched with the first connecting block.

More preferably, the main body beam is a ladder beam.

More preferably, the prefabricated butt strap is provided with longitudinal steel bars and transverse steel bars.

Compared with the prior art, the invention has the following advantages:

compared with the prior art, the prefabricated spliced bridgehead anti-settling structure is convenient for later maintenance and replacement of the butt strap structure, and the pile foundation structure, the cap beam structure, the butt strap structure and the like can be prefabricated in a factory, and only a small amount of cast-in-place concrete is needed on site; the butt strap and the cap beam are connected through the plate connecting pieces, so that the butt strap and the cap beam are convenient and quick to use, and the butt strap and the cap beam can be replaced by directly detaching the connecting pieces when the butt strap structure needs to be replaced; if the roadbed needs to be reprocessed, the connecting piece is also dismounted, the roadbed can be reprocessed, the construction is simple, and the method is economical and environment-friendly.

Drawings

FIG. 1 is a schematic view of a vertical structure of a bridgehead anti-settling structure according to the present invention;

FIG. 2 is a schematic cross-sectional view of the anti-settling structure of the bridgehead according to the present invention;

FIG. 3 is a schematic plan view of the anti-settling structure of the bridgehead according to the present invention;

FIG. 4 is a schematic illustration of reinforcement of the prefabricated panel of the present invention;

fig. 5 is a schematic structural view of the plate connecting member according to the present invention;

fig. 6 is a schematic structural view of the precast cap beam of the present invention.

The reference numbers in the figures indicate:

1. abutment, 2, pavement structure layer, 3, attachment strap structure layer, 4, plain concrete layer, 5, rubble bed course, 6, pile foundation structure, 7, roadbed layer, 31, prefabricated attachment strap, 32, plate connecting piece, 311, second draw-in groove, 312, longitudinal reinforcement, 313, horizontal reinforcement, 321, first connecting block, 322, second connecting block, 323, screw, 324, first draw-in groove, 61, prefabricated pile foundation, 62, prefabricated cap beam, 621, main body roof beam, 622, third draw-in groove, 623, through-hole.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

The invention relates to a bridgehead anti-settlement structure adopting a prefabricated assembly process, which is structurally shown in figure 1 and comprises a bridge abutment 1, a pavement structure layer 2, a butt strap structure layer 3, a plain concrete layer 4, a broken stone cushion layer 5, a pile foundation structure 6 and a road base layer 7, wherein the pavement structure layer 2 is laid on the butt strap structure layer 3, one end of the butt strap structure layer 3 is erected on the bridge abutment 1 and is hinged with the bridge abutment 1, the pile foundation structure 6 is connected with the butt strap structure layer 3, the plain concrete layer 4 and the broken stone cushion layer 5 are sequentially laid between the butt strap structure layer 3 and the road base layer 7, the butt strap structure layer 3 and the pile foundation structure 6 are both prefabricated concrete structures, the butt strap structure layer 3 and the pile foundation structure 6 which are prefabricated are directly assembled on a construction site, and the pile foundation structure 6 is fixed by using cast-in-place concrete.

The structure of each layer in this embodiment is described below:

1. road surface structure layer

The pavement structure layer 2 should be designed according to the road grade, for example, the design of the urban main road is sequentially from bottom to top: 6mm slurry seal, 80mm coarse-grained asphalt concrete (AC-25C), 60mm medium-grained asphalt concrete (AC-20C), and 40mm asphalt mastic macadam mixture SMA-13(SBS modified).

2. Structure layer of butt strap

One end of the butt strap structural layer 3 is erected on the abutment bracket, and the butt strap structural layer 3 is connected with the abutment 1 in a hinged mode through the embedded dowel bars of the abutment back. One end of the butt strap structure layer 3 is connected with a prefabricated cap beam 62 arranged on the pile top of a prefabricated pile foundation 61 through a plate connecting piece 32 to form a two-span or multi-span structure. The length of the prefabricated butt strap 31 is set differently according to the filling height and the foundation condition. The prefabricated butt straps 31 are also connected through a plate connecting piece 32, and water-stopping materials such as asphalt mastic are filled in the gap between two adjacent butt straps.

The plate connecting member 32 includes two first connecting blocks 321, a second connecting block 322 and a screw 323 for connecting the two first connecting blocks 321, the two first connecting blocks 321 are respectively installed on two adjacent prefabricated straps 31, the first connecting block 321 is provided with a first clamping groove 324 matched with the second connecting block 322, the second connecting block 322 is installed in the first clamping groove 324, two ends of the second connecting block 322 are respectively connected with the first connecting blocks 321 through the screw 323, and the prefabricated straps 31 are provided with a second clamping groove 311 matched with the first connecting blocks 321.

In order to reinforce the prefabricated butt strap 31, the prefabricated butt strap 31 of the present embodiment is provided with longitudinal reinforcing bars 312 and transverse reinforcing bars 313.

3. Plain concrete layer

The concrete is poured on the gravel cushion layer 5, the two transverse sides of the plain concrete layer 4 are wider than the bridge head butt straps by 100 mm respectively, and the plain concrete layer 4 plays a role in stress diffusion and can reduce or eliminate the phenomenon of secondary vehicle jumping at the far ends of the butt straps.

4. Gravel cushion

The gravel cushion 5 is laid on the road base course 7, can play a role of diffusion stress when treating soft foundation, can drain water, and accelerates consolidation and settlement of a lower soil layer.

5. Pile foundation structure

Adopt prefabricated pile foundation structure, can adopt concrete or steel construction, set up in the middle part and the tip of preventing subsiding the structure, can calculate according to subsiding, set up and adopt different pile footpaths and pile length. The prefabricated cap beam 62 arranged at the top of the prefabricated pile foundation 61 is of a concrete structure, is connected with the prefabricated pile foundation 61 in a cast-in-place concrete mode, and is used for transmitting the stress of the butt strap structure to the prefabricated pile foundation 61 arranged below.

The precast hat beam 62 includes a body beam 621, a third catching groove 622 on the body beam 621, and a through hole 623 for receiving the precast pile foundation 61 and the cast-in-place concrete, the third catching groove 622 matching with the first connection block 321.

The prefabricated hat girders 62 in this embodiment are trapezoidal girders that are better connected to the decking structure 2.

6. Road base layer

When the filling is processed after the platform, the filling is required to be tamped in layers, the filling height of each layer of soil is limited, 15% of lime or 5% of cement is added into the backfilling material according to the property of the soil, the strength is required to be more than or equal to 0.6Mpa, and the compaction degree is strictly controlled.

The use method of the anti-settling structure in the embodiment is as follows:

according to the road pavement load and the roadbed condition of on-site excavation, a pile foundation structure 6 meeting the requirement of bridge head settlement control is designed, the pile foundation structure 6 is prefabricated in a factory, transported to the on-site, constructed by static pressure or vibration, and constructed to the required elevation, meanwhile, the treatment of a roadbed layer 7 is synchronously implemented, and the treatment range of the roadbed and the length of the butt strap structure layer 3 are determined according to the treatment range. The prefabricated cap beam 62 is connected with the prefabricated pile foundation 61 through cast-in-place concrete. When the roadbed is treated, layered tamping is required, the filling height is controlled, and gradual transition of the flexible roadbed to a rigid bridge structure is considered.

The butt strap structure layer 3 is prefabricated in a factory, before concrete is poured, the first connecting block 321 of the plate connecting piece 32 needs to be placed into the second clamping groove 311 on the prefabricated butt strap 31, the reinforcing bars of the butt strap structure generally need to be provided with butt strap longitudinal reinforcing bars 312 and transverse reinforcing bars 313, and after the concrete is poured, the butt strap structure layer is maintained in the factory to the strength required by the butt strap structure. After the prefabricated butt strap is transported to the site, the prefabricated butt strap 31 is hoisted to a specified position, one end of the prefabricated butt strap is erected on a bracket of the abutment 1, the inserted bars pre-embedded in the abutment back penetrate through the plastic hoses reserved in the butt strap structure, and the supporting position between the abutment brackets is provided with an oil felt cushion layer, so that the butt strap structure is hinged. A gap is arranged between the bridge abutment and the abutment back, and asphalt mastic water-stop material is filled in the gap, so that the expansion of the access board structure layer 3 can be buffered, and water can be stopped. The other end of the butt strap structure layer 3, make prefabricated pile foundation 61 link up with prefabricated cap beam 62 through cast in situ concrete at middle part and tip, adopt plate connecting piece 32 to connect between butt strap and the butt strap, fill pitch mastic stagnant water material in the gap of two adjacent plates. A plain concrete layer 4 and a gravel cushion layer 5 are sequentially arranged below the butt strap structure layer 3.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A prefabricated spliced bridge head anti-settlement structure comprises a bridge abutment (1), a pavement structure layer (2), a butt-strap structure layer (3), a plain concrete layer (4), a broken stone cushion layer (5), a pile foundation structure (6) and a road base layer (7); the pavement structure layer (2) is laid on the butt-strap structure layer (3); one end of the butt strap structure layer (3) is erected on the abutment (1); the pile foundation structure (6) is connected with the lap structure layer (3); plain concrete layer (4) and rubble bed course (5) lay between attachment strap structural layer (3) and roadbed layer (7) in proper order, its characterized in that, attachment strap structural layer (3) and pile foundation structure (6) be prefabricated structure, directly will assemble prefabricated attachment strap structural layer (3) and pile foundation structure (6) at the job site to use the fixed pile foundation structure of cast in situ concrete (6).

2. The prefabricated spliced bridgehead anti-settlement structure of claim 1, wherein one end of the butt strap structure layer (2) is hinged with the abutment (1).

3. The prefabricated spliced bridgehead anti-settlement structure of claim 1, wherein the butt strap structure layer (3) comprises a plurality of prefabricated butt straps (31) and butt strap connectors (32); the prefabricated butt straps (31) are connected through plate connecting pieces (32).

4. The prefabricated spliced bridgehead anti-settlement structure of claim 3, wherein gaps are formed between the prefabricated butt strap (31), and water stopping materials are filled in the gaps; the water stopping material is asphalt mastic.

5. A prefabricated spliced bridgehead anti-settlement structure according to claim 3, wherein the plate connecting member (32) comprises two first connecting blocks (321), a second connecting block (322) for connecting the two first connecting blocks (321), and a screw (323); the two first connecting blocks (321) are respectively arranged on two adjacent prefabricated butt straps (31); the first connecting block (321) is provided with a first clamping groove (324) matched with the second connecting block (322); the second connecting block (322) is arranged in the first clamping groove (324); two ends of the second connecting block (322) are respectively connected with the first connecting block (321) through screws (323).

6. The prefabricated spliced bridgehead anti-settling structure of claim 5, wherein the prefabricated butt strap (31) is provided with a second clamping groove (311) matched with the first connecting block (321).

7. A prefabricated spliced bridgehead anti-settling structure according to claim 5, wherein the pile foundation structure (6) comprises prefabricated pile foundations (61) and prefabricated cap beams (62); the prefabricated pile foundation (61) is connected with the prefabricated cap beam (62) through cast-in-place concrete; the prefabricated cap beam (62) is connected with the lap plate structure layer (3) through a plate connecting piece (32).

8. The prefabricated spliced bridgehead anti-settlement structure of claim 7, wherein the prefabricated cap beam (62) comprises a main body beam (621), a third clamping groove (622) positioned on the main body beam (621) and a through hole (623) for accommodating a prefabricated pile foundation (61) and cast-in-place concrete; the third card slot (622) is matched with the first connecting block (321).

9. A prefabricated spliced bridgehead anti-subsidence structure according to claim 8, wherein the main body beam (621) is a ladder beam.

10. The prefabricated spliced bridgehead anti-settlement structure of claim 3, wherein the prefabricated butt strap (31) is provided with longitudinal steel bars (312) and transverse steel bars (313).