Construction method for long-distance box culvert with shallow covering soil penetrating through railway yard

Abstract

The invention relates to a construction method of a long-distance box culvert for shallow covering soil to penetrate through a railway yard, which comprises the following steps: respectively constructing two working pits on two sides of an existing railway line, and respectively prefabricating a box culvert section in the two working pits; auxiliary beam structures are constructed at the corresponding positions of the existing railway line where the two box culvert sections are about to pass through, the auxiliary beam supporting structures carry out temporary overhead supporting on the existing railway line, and each box culvert section is correspondingly provided with the corresponding construction auxiliary beam structure; the two box culvert sections are jacked, so that the two box culvert sections are in place; and a cast-in-place foundation pit is excavated at the butt joint position between the two box culvert sections, the two jacked box culvert sections serve as access channels, and cast-in-place sequential connection of the two box culvert sections is completed in the cast-in-place foundation pit. The method has the advantages that under the condition that the railway operation is not interrupted, the shallow covering soil passes through the railway station yard, the problems that the number of station tracks is large, the distance is long, the risk is large, and the precision is high are solved, and a new thought and method are provided for urban roads to pass through the operating railway station.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of frame bridge structure, and particularly relates to a construction method of shallow-covering long-distance box culvert crossing railway station. BACKGROUND

[0002] The railway station that has been built for many years often cuts the city traffic and is always regarded as the first traffic problem to be solved.

[0003] The railway station can be crossed by two ways of overpassing or underpassing. The overpassing often adopts bridge rotation, and the underpassing often adopts shield. The rotation construction has less influence on the railway station transportation, but is easily restricted by the nearby high buildings and cannot be implemented, and is controlled by the railway building limit under the bridge, and the road longitudinal slope of the overpassing bridge is large, and the pedestrians and non-motor vehicles are difficult to go up the bridge. The shield underpassing has many unfavorable factors such as long road line caused by thick covering soil thickness, ventilation and disaster prevention, and poor landscape integration with the surrounding land.

[0004] After the newly-built road underpasses the existing railway station, the road needs to be connected to the existing roads on both sides. Due to the length of the underpassing section and the existing road elevation, it is very important to find a bridge construction method with small covering soil thickness of the underpassing station and easy road connection. SUMMARY

[0005] The present application aims at solving the problems of the prior art, and provides a construction method of shallow-covering long-distance box culvert crossing railway station, which divides the long-distance box culvert underpassing the railway station into a combination of jacking section + cast-in-place section + jacking section, jacks the prefabricated box culverts from both sides of the railway, and then connects the jacked box culverts, so as to solve the problem of the city road crossing the railway station without interrupting the railway operation.

[0006] The present application is achieved by the following technical scheme: A construction method of shallow-covering long-distance box culvert crossing railway station, which is used for crossing the existing railway line and has the characteristics that the construction method comprises the following steps: Two working pits are respectively constructed on both sides of the existing railway line, and two box culvert sections are respectively prefabricated in the two working pits; A convenient beam structure is constructed at the corresponding position of the existing railway line where the two box culvert sections cross, the convenient beam support structure temporarily supports the existing railway line, and each box culvert section is respectively provided with a construction convenient beam structure; The two box culvert sections are respectively jacked to be in place; A cast-in-place foundation pit is excavated at the joint position between the two box culvert sections, the two jacked box culvert sections are used as the access passage, and the cast-in-place connection of the two box culvert sections is completed in the cast-in-place foundation pit.

[0007] The working pit is arranged on the ground on both sides of the existing railway line, and comprises a waterproof curtain, supporting piles, back protection piles and a bottom plate, the waterproof curtain is arranged at the outermost periphery of the working pit, the supporting piles and the back protection piles are arranged inside the waterproof curtain, and the bottom plate is arranged at the bottom of the working pit and inside the enclosed area of the supporting piles and the back protection piles.

[0008] The waterproof curtain adopts cement-soil mixing piles or high-pressure rotary jet piles, the supporting piles adopt bored piles, the back protection piles adopt bored piles, and the bottom plate adopts a reinforced concrete structure.

[0009] The convenient beam structure comprises a plurality of longitudinal beams arranged in parallel with the direction of the existing railway line, adjacent longitudinal beams are connected by transverse beams to form an integral structure, and a convenient beam strip foundation arranged in the direction crossing the existing railway line is arranged below the longitudinal beams, and convenient beam strip pile foundations are arranged below both ends of the convenient beam strip foundation.

[0010] A convenient beam strip foundation waterproof curtain is arranged at the periphery of the convenient beam structure.

[0011] The present application has the advantages that it has strong practicability and solves the problem of crossing the existing railway station of the city broken road. The long distance box culvert under the railway station is connected in three sections, namely jacking + cast-in-place + jacking, the prefabricated box culvert is jacked from both sides of the railway, then the cast-in-place connection of the jacked box culvert is carried out. One working pit is arranged on each side of the railway to prefabricate the box culvert, after the railway line is raised by the steel convenient beam, the box culvert on one side of the railway is jacked to the lower side of the railway, then the box culvert on the other side of the railway is jacked to the lower side of the railway, finally, the jacked box culvert is used as an access passage to complete the cast-in-place connection. The railway operation is not interrupted, the jacking distance is short, the soil covering is shallow, the road is easy to connect, and a new idea and method are provided for solving the problem of crossing the railway station of the city road. It has high popularization and application value. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a schematic view of step one (north side) of the present application; Figure 2 It is a schematic view of step one (south side) of the present application; Figure 3 It is a schematic view of the cast-in-place strip foundation in step two (north side) of the present application; Figure 4 It is a schematic view of the construction strip foundation in step two (north side) of the present application; Figure 5 It is a schematic view of jacking one box culvert in step three (north side) of the present application; Figure 6 It is a schematic view of jacking another box culvert in step three (north side) of the present application; Figure 7 Schematic diagram of the cast-in-place strip foundation in step 4 (south side) of the present invention; Figure 8 This is a schematic diagram of the construction of the strip foundation in step 4 (south side) of the present invention; Figure 9 A schematic diagram of jacking a box culvert in step five (south side) of the present invention; Figure 10 This is a schematic diagram of jacking another box culvert in step five (south side) of the present invention; Figure 11 This is a schematic diagram of the cast-in-situ box culvert in step six of the present invention. DETAILED DESCRIPTION

[0013] The features of the present invention and other related features are further described in detail below through embodiments in conjunction with the accompanying drawings to facilitate understanding by those skilled in the art: like Figures 1-11 As shown in the figure, the marks respectively represent: the center line 1 of the first railway line, the center line 2 of the second railway line, the center line 3 of the third railway line, the center line 4 of the fourth railway line, the center line 5 of the fifth railway line, the center line 6 of the sixth railway line, the center line 7 of the seventh railway line, the center line 8 of the eighth railway line, the working pit water-stop curtain Q1, the working pit support piles Q2, the working pit back protection piles Q3-1, the working pit bottom plate Q3-2, the new box culvert Q4, the D16 temporary beam Q5, the temporary beam strip foundation reinforcement piles Q6, the temporary beam strip foundation pile foundation Q7, the temporary beam strip foundation Q8, the temporary beam strip foundation water-stop curtain Q9, the line support piles Q10, and the cast-in-place foundation pit Q11.

[0014] Example: Figures 1 to 11 As shown, the construction method of the shallow earth covering long-distance box culvert crossing the railway station in this embodiment mainly includes the following steps: The box culvert under the railway yard was constructed in three phases: jacking in the north box culvert, jacking in the south box culvert, and finally casting the intermediate connecting section box culvert. Specifically, the box culverts Q4 on both sides of the railway were prefabricated, the D16 temporary beam Q5 was erected, and the cast-in-place strip foundation Q8 was installed. The D16 temporary beam Q5 was then installed and jacked into the two newly constructed box culverts Q4 on the north side of the railway. The D16 temporary beam Q5 was then installed and the cast-in-place strip foundation Q8 was installed. The D16 temporary beam Q5 was then installed and jacked into the two newly constructed box culverts Q4 on the south side. Using strip foundation bored piles Q7 and inter-track bored piles Q10 as support, the open-cut cast-in-place box culvert Q4 was constructed, completing the multi-track, long-distance box culvert under the railway yard.

[0015] Specifically, the following steps are included.

[0016] Step one: construction of working pit and prefabricated box body: construction of water stop curtain Q1 around the working pit, working pit support pile Q2 around the working pit, excavation of working pit, pouring of working pit bottom plate Q3-2 and working pit back protection pile Q3-1, prefabrication of box culvert Q4.

[0017] In this embodiment, the jacking working pit is set on the ground on both sides of the railway, which is composed of water stop curtain Q1, jacking working pit support pile Q2, working pit back protection pile Q3-1 and working pit bottom plate Q3-2.

[0018] The water stop curtain Q1 is set around the working pit, and the jacking working pit support pile Q2 is set outside. Cement-soil mixing pile or high-pressure rotary jet pile can be used to form a closed area to prevent seepage of underground water and meet the requirement of not causing settlement of adjacent buildings when dewatering in the pit.

[0019] The working pit support pile Q2 is set around the working pit bottom plate Q3-2, and all are bored piles to form a closed area to meet the construction requirements of working pit foundation pit excavation.

[0020] The working pit back protection pile Q3-1 is a bored pile, and the pile diameter and length are determined in combination with the jacking weight and geological conditions.

[0021] The working pit bottom plate Q3-2 is set under the newly built frame bridge and is a reinforced concrete structure. Its bottom is considered for foundation reinforcement in combination with the geological conditions, and its top is coated with paraffin to reduce the jacking friction resistance.

[0022] The newly built box culvert Q4 is a reinforced concrete structure, which can be prefabricated in the working pit or directly cast in situ by open excavation under the railway. The prefabricated box culvert needs to be jacked into the railway by a jack, and the box culvert is used for passing motor vehicles, non-motor vehicles or pedestrians, and the box culvert top plate directly bears the live load of the railway.

[0023] Step two: construction of north side of strip foundation: erecting D16m strip beam Q5 on railway center line one 1, railway center line two 2, railway center line three 3 and railway center line four 4, construction of strip foundation pile Q7, strip foundation reinforcement pile Q6, strip foundation Q8 and strip foundation water stop curtain Q9, and construction of line interval support pile Q10.

[0024] The D16 strip beam Q5 is a steel structure, which uses longitudinal beams parallel to the railway to support the railway line, and uses multiple horizontal beams with consistent spacing to connect the longitudinal beams. The live load of the railway is transferred to the strip beam, and then to the strip foundation Q8 and strip foundation pile Q7.

[0025] In this embodiment, the strip foundation pile Q7 is a hole-digging pile, which is set below the strip foundation Q8 to stabilize the strip foundation and bear the load of the strip foundation and the upper part.

[0026] The convenient beam strip foundation Q8 adopts reinforced concrete, and the support of the D16 convenient beam Q5 is arranged on the top of the convenient beam strip foundation Q8.

[0027] The convenient beam strip foundation Q8 adopts reinforced concrete, and the support of the D16 convenient beam Q5 is arranged on the top of the convenient beam strip foundation Q8.

[0028] The convenient beam strip foundation Q8 adopts reinforced concrete, and the support of the D16 convenient beam Q5 is arranged on the top of the convenient beam strip foundation Q8.

[0029] The convenient beam strip foundation Q8 adopts reinforced concrete, and the support of the D16 convenient beam Q5 is arranged on the top of the convenient beam strip foundation Q8.

[0030] Step three: jacking the north box body: erecting three-hole D16m convenient beams Q5 on the railway line center line one 1, the railway line center line two 2, the railway line center line three 3 and the railway line center line four 4 → cutting soil to jacking the first-hole new box culvert Q4 → moving the D16m convenient beams Q5 → removing the middle convenient beam strip foundation Q8 → cutting soil to jacking the second-hole new box culvert Q4.

[0031] Step four: constructing the south convenient beam strip foundation: erecting D16m convenient beams Q5 on the railway line center line five 5, the railway line center line six 6, the railway line center line seven 7 and the railway line center line eight 8 → constructing the convenient beam strip foundation pile Q7, the convenient beam strip foundation reinforcement pile Q6, the convenient beam strip foundation Q8 and the convenient beam strip foundation waterproof curtain Q9.

[0032] Step five: jacking the north box body: erecting three-hole D16m convenient beams Q5 on the railway line center line five 5, the railway line center line six 6, the railway line center line seven 7 and the railway line center line eight 8 → cutting soil to jacking the first-hole new box culvert Q4 → moving the D16m convenient beams Q5 → removing the middle convenient beam strip foundation Q8 → cutting soil to jacking the second-hole new box culvert Q4.

[0033] Step six: casting the box body: excavating the cast-in-place foundation pit Q11 → removing the line support pile Q10 → pouring the box body Q4.

[0034] Although the above embodiments have been described in detail with reference to the accompanying drawings, those skilled in the art can recognize that various improvements and changes can be made to the present application without departing from the scope defined by the claims, and therefore, detailed description is not given here.

Claims

1. A construction method for a shallow earth-covered long-distance box culvert crossing a railway station, used to cross an existing railway line, characterized by: The construction method comprises the following steps: Two working pits are constructed on both sides of the existing railway line, and one box culvert segment is prefabricated in each of the two working pits; Constructing temporary beam structures at corresponding positions of the existing railway line that the two box culvert sections are intended to cross, the temporary beam support structures temporarily supporting the existing railway line overhead, and each box culvert section is respectively provided with a corresponding temporary beam structure; Jacking the two box culvert segments separately to put the two box culvert segments into place; A cast-in-situ foundation pit is excavated at the joint position between the two box culvert segments, and the two box culvert segments that have been pushed in are used as inlet and outlet passages, and the cast-in-situ connection of the two box culvert stages is completed in the cast-in-situ foundation pit.

2. The method for constructing a long-distance box culvert with shallow earth covering across a railway station according to claim 1, characterized in that: The working pit is set on the ground on both sides of the existing railway line, and includes a water-stop curtain, support piles, back protection piles and a bottom plate. The water-stop curtain is set at the outermost edge of the working pit, the support piles and the back protection piles are set on the inner side of the water-stop curtain, and the bottom plate is set at the bottom of the working pit and is located inside the enclosed area of ​​the support piles and the back protection piles.

3. The method for constructing a long-distance box culvert with shallow earth covering across a railway station according to claim 2, characterized in that: The water-stop curtain adopts cement-soil mixing piles or high-pressure rotary jet piles; the supporting piles adopt bored cast-in-place piles; the back protection piles adopt bored cast-in-place piles; and the bottom plate adopts reinforced concrete structure.

4. The method for constructing a long-distance box culvert with shallow earth covering across a railway station according to claim 1, characterized in that: The temporary beam structure includes several longitudinal beams arranged parallel to the direction of the existing railway line. Adjacent longitudinal beams are connected by cross beams to form an integral structure. A temporary beam strip foundation is arranged below the longitudinal beams and crosses the direction of the existing railway line. Temporary beam strip foundation piles are arranged below both ends of the temporary beam strip foundation.

5. The method for constructing a long-distance box culvert with shallow earth covering across a railway station according to claim 4, characterized in that: A temporary beam strip foundation water-stop curtain is arranged on the periphery of the temporary beam structure.

Images