Construction method for face support structure of pipe curtain top pipe group tunneling shaft

Abstract

The present invention discloses a face support structure and construction method for a pipe curtain top pipe group excavation shaft, including an excavation face formed by a plurality of face retaining piles; an upper row of pipe curtains and a lower row of pipe curtains are respectively arranged above and below the underground structure to be constructed; the upper row of pipe curtains includes a plurality of upper row of steel pipes; the lower row of pipe curtains includes a plurality of lower row of steel pipes; the plurality of upper row of steel pipes, the plurality of lower row of steel pipes and the plurality of face retaining piles correspond to each other; each face retaining pile is connected to the corresponding upper row of steel pipes and the corresponding lower row of steel pipes at a position near the upper end and a position near the middle. During construction, first, all face retaining piles of the excavation face are constructed; then, the construction of the upper row of pipe curtains and the construction of the lower row of pipe curtains are completed in sequence; finally, a plurality of face retaining piles are cut off as required, the excavation face is opened, and the construction of the underground structure is completed. The present invention is aimed at the pipe curtain construction, and when the retaining piles are cut off one by one, the foundation pit of the working shaft face is ensured to be stable.

Description

Technical Field

[0001] The invention relates to the technical field of urban road reconstruction, and in particular to a construction method for a tunnel face support structure used for a pipe curtain top pipe group tunneling shaft. Background Art

[0002] During the process of urban road renewal and reconstruction, the pipe curtain method is used for support because the traffic cannot be interrupted or important buildings (structures) are passed underground; the working shaft foundation pit is often supported by retaining piles. Because the pipe curtain construction period is long and the retaining piles need to be cut off one by one during the pipe curtain construction, it is not conducive to the stability of the foundation pit of the working shaft heading.

[0003] Therefore, for pipe curtain construction, how to ensure the stability of the foundation pit at the working shaft face when cutting the retaining piles one by one becomes a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] In view of the above-mentioned defects of the prior art, the present invention provides a face support structure and a construction method for a pipe curtain top pipe group tunneling shaft, the purpose of which is to ensure the stability of the foundation pit at the working shaft face when cutting off the retaining piles one by one during the pipe curtain construction.

[0005] To achieve the above-mentioned purpose, the present invention discloses a tunnel face support structure for a pipe curtain top pipe group tunneling shaft, which is arranged in the pipe curtain tunneling working shaft, corresponding to the side wall of the underground structure to be constructed, and includes a tunneling tunnel face formed by a number of tunnel face retaining piles evenly distributed in the horizontal direction.

[0006] Wherein, an upper row pipe curtain and a lower row pipe curtain are respectively arranged above and below the underground structure to be constructed; the upper row pipe curtain comprises a plurality of upper row steel pipes; the lower row pipe curtain comprises a plurality of lower row steel pipes;

[0007] The plurality of upper row steel pipes, the plurality of lower row steel pipes and the plurality of tunnel face retaining piles correspond to each other;

[0008] The position near the upper end and the position near the middle of the tunnel face are respectively connected to the upper row of pipe curtains and the lower row of pipe curtains, that is, the position near the upper end and the position near the middle of each tunnel face retaining pile are respectively connected to the corresponding upper row of steel pipes and the corresponding lower row of steel pipes;

[0009] The exposed ends of the plurality of upper row steel pipes and the exposed ends of the plurality of lower row steel pipes are welded with steel plates to form steel pipe curtain pipe openings.

[0010] Preferably, a steel corbel is provided between each of the tunnel face retaining piles and the corresponding upper row of steel pipes and the corresponding lower row of steel pipes.

[0011] More preferably, each of the steel corbels comprises two steel plates vertically arranged and parallel to each other;

[0012] An arc-shaped connecting steel plate is provided at one end of the two steel plates; and the parts between the two steel plates close to the other end are connected by a horizontally arranged angle steel.

[0013] More preferably, the arc-shaped connecting steel plate of each of the steel corbels is connected to the corresponding pipe opening of the steel pipe curtain by welding;

[0014] The two steel plates of each steel corbel are connected to the corresponding embedded steel plates on the side walls of the face retaining piles by welding.

[0015] Preferably, for a deeper foundation pit with a depth exceeding 10 m, an inclined brace is provided on the side of the excavation face facing the pipe curtain excavation working shaft.

[0016] The present invention also provides a construction method for a tunnel face support structure for a pipe curtain top pipe group tunneling well, the steps of which are as follows:

[0017] Step 1, excavating the pipe-roof excavation working shaft to the first excavation surface for constructing the tunnel face retaining piles, and constructing all the tunnel face retaining piles of the excavation tunnel face;

[0018] Step 2, excavating the pipe-roof excavation working pit to the second excavation face for constructing the upper row of pipe-roofs; cutting off each of the face retaining piles near the upper end, where the position for setting the upper row of pipe-roofs is to be set; and completing the setting of the corresponding upper row of steel pipes at the position where each of the face retaining piles is cut off near the upper end, thereby completing the construction of the upper row of pipe-roofs;

[0019] Step 3, after the construction of the upper row of pipe curtains is completed, continue to excavate the pipe curtain excavation working shaft to the fourth excavation face for constructing the lower row of pipe curtains; cut off the position of each of the tunnel face retaining piles near the middle for setting the lower row of pipe curtains; and complete the setting of the corresponding lower row of steel pipes at the position of the cut-off near the middle of each of the tunnel face retaining piles, thereby completing the construction of the lower row of pipe curtains;

[0020] Step 4: After the construction of the upper row of pipe curtains and the lower row of pipe curtains is completed, a number of the tunnel face retaining piles are cut off as required, the excavation tunnel face is opened, and the construction of the underground structure is completed.

[0021] Preferably, in step 2, when constructing the upper row of steel pipes one by one, a steel corbel is arranged between each of the upper row of steel pipes and the corresponding face retaining piles for fixation, and in step 4, when a number of the face retaining piles are cut off, they are removed.

[0022] Preferably, for a deeper foundation pit with a depth exceeding 10 m, between step 2 and step 3, an inclined brace is added when the pipe curtain excavation working shaft is excavated to the third excavation surface.

[0023] Preferably, in step 3, when constructing the lower row of steel pipes one by one, a steel corbel is arranged between each lower row of steel pipes and the corresponding face retaining piles for fixation, and in step 4, the steel corbels are removed when a number of face retaining piles are cut off.

[0024] Beneficial effects of the present invention:

[0025] The present invention aims at pipe curtain construction and ensures the stability of the foundation pit of the working shaft face when the retaining piles are cut off one by one.

[0026] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the side structure of the tunnel face retaining piles constructed according to an embodiment of the present invention is shown.

[0028] Figure 2 A schematic diagram of the side structure of an upper row pipe curtain constructed according to an embodiment of the present invention is shown.

[0029] Figure 3 A schematic diagram of the end structure of an upper row of pipe curtains constructed according to an embodiment of the present invention is shown.

[0030] Figure 4 A schematic diagram of the side structure of the inclined brace constructed according to an embodiment of the present invention is shown.

[0031] Figure 5 A schematic diagram of the end structure of an inclined brace constructed according to an embodiment of the present invention is shown.

[0032] Figure 6 A schematic diagram of the side structure of the lower pipe curtain constructed according to an embodiment of the present invention is shown.

[0033] Figure 7 A schematic diagram of the end structure of a lower pipe curtain constructed according to an embodiment of the present invention is shown.

[0034] Figure 8 A schematic diagram of the side structure of opening the tunneling face according to an embodiment of the present invention is shown.

[0035] Fig. 9 A schematic diagram of the end face structure of opening a tunneling face according to an embodiment of the present invention is shown.

[0036] Fig.10A schematic diagram of the end structure of a tunnel face retaining pile connected to a steel pipe curtain pipe opening through a steel corbel in one embodiment of the present invention is shown.

[0037] Fig.11 A schematic diagram of the side structure of a tunnel face retaining pile connected to a steel pipe curtain pipe opening through a steel corbel in one embodiment of the present invention is shown. DETAILED DESCRIPTION

[0038] Example

[0039] like Figure 8 As shown, the face support structure for the pipe-curtain top pipe group excavation shaft is arranged in the pipe-curtain excavation working shaft, corresponding to the side wall of the underground structure 9 to be constructed, and includes an excavation face 1 formed by a number of face retaining piles 2 evenly distributed in the horizontal direction.

[0040] An upper pipe curtain 3 and a lower pipe curtain 6 are respectively arranged above and below the underground structure 9 to be constructed; the upper pipe curtain 3 includes a plurality of upper steel pipes; the lower pipe curtain 6 includes a plurality of lower steel pipes;

[0041] The plurality of upper row steel pipes, the plurality of lower row steel pipes and the plurality of tunnel face retaining piles 2 correspond to each other;

[0042] The upper and middle positions of the tunnel face 1 are respectively connected to the upper pipe curtain 3 and the lower pipe curtain 6, that is, the upper and middle positions of each tunnel face retaining pile 2 are respectively connected to the corresponding upper and lower steel pipes;

[0043] The exposed ends of the upper row of steel pipes and the exposed ends of the lower row of steel pipes are welded with steel plates to form steel pipe curtain pipe openings 7.

[0044] like Fig.10 and Fig.11 As shown, in certain embodiments, a steel corbel 4 is provided between each face retaining pile 2 and the corresponding upper row of steel pipes and the corresponding lower row of steel pipes.

[0045] In some embodiments, each steel corbel 4 includes two steel plates 8 vertically disposed and parallel to each other;

[0046] An arc-shaped connecting steel plate 9 is provided at one end of the two steel plates 8 ; the portions between the two steel plates 8 near the other end are connected by a horizontally arranged angle steel 10 .

[0047] The principle of the present invention is as follows:

[0048] The pipe curtain excavation working pit adopts the face retaining piles 2 as the foundation pit support structure, and forms the excavation face 1. Before the excavation of the upper row of pipe curtains 3 and the lower row of pipe curtains 6, the face retaining piles 2 are cut off one by one;

[0049] The upper row of steel pipes of the upper row of pipe curtain 3 and the lower row of steel pipe curtain 6, as well as the lower row of steel pipes, are excavated at the cut-off position of the corresponding tunnel face retaining pile 2, and the exposed ends of several upper row of steel pipes and several lower row of steel pipes are welded with steel plates to form steel pipe curtain pipe openings 7, and are fixed by steel brackets 4;

[0050] During the subsequent excavation of the foundation pit and the excavation of the upper and lower pipe curtains 3 and 6, the cut-off face retaining piles 2 are fixed to the upper and lower pipe curtains 3 or 6 that have been excavated by the steel brackets 4 to maintain the stability of the working pit.

[0051] In some embodiments, the arc-shaped connecting steel plate 9 of each steel corbel 4 is connected to the corresponding steel pipe curtain pipe opening 7 by welding;

[0052] The two steel plates 8 of each steel corbel 4 are connected to the embedded steel plates 11 on the side walls of the corresponding face retaining piles 2 by welding.

[0053] In some embodiments, for a deeper foundation pit with a depth exceeding 10 m, a diagonal brace 5 is provided on one side of the excavation face 1 facing the pipe-roof excavation working shaft.

[0054] The present invention also provides a construction method for a tunnel face support structure for a pipe curtain top pipe group tunneling well, the steps of which are as follows:

[0055] like Figure 1 As shown, step 1, excavating the pipe curtain excavation working shaft to the first excavation surface for constructing the tunnel face retaining piles 2, and constructing all the tunnel face retaining piles 2 of the tunnel face 1;

[0056] like Figure 2 and Figure 3 As shown, step 2, excavate the second excavation face for constructing the upper row of pipe curtains 3 in the pipe curtain excavation working shaft; cut off each face retaining pile 2 near the upper end, where the position for setting the upper row of pipe curtains 3 is to be set; and complete the setting of the corresponding upper row of steel pipes at the position where each face retaining pile 2 is cut off near the upper end, thereby completing the construction of the upper row of pipe curtains 3;

[0057] like Figure 6 and Figure 7 As shown, after the construction of the upper pipe curtain 3 is completed in step 3, the fourth excavation face for constructing the lower pipe curtain 6 is continued in the pipe curtain excavation working shaft; each face retaining pile 2 is cut off near the middle for setting the position of the lower pipe curtain 6; and the corresponding lower row steel pipe is set at the position of the cut-off near the middle of each face retaining pile 2, completing the construction of the lower pipe curtain 6;

[0058] like Figure 8 and Fig. 9As shown, in step 4, after the construction of the upper pipe curtain 3 and the lower pipe curtain 6 is completed, a number of tunnel face retaining piles 2 are cut off as required, the excavation tunnel face 1 is opened, and the construction of the underground structure 9 is completed.

[0059] In some embodiments, in step 2, when the upper row of steel pipes are constructed one by one, steel brackets are arranged between each upper row of steel pipes and the corresponding tunnel face retaining piles 2 for fixation, and in step 4, when a number of tunnel face retaining piles 2 are cut off, they are dismantled.

[0060] like Figure 4 and Figure 5 As shown, in some embodiments, for a deeper foundation pit with a depth exceeding 10 m, between step 2 and step 3, an inclined brace 5 is added when the pipe curtain excavation working shaft is excavated to the third excavation surface.

[0061] In some embodiments, in step 3, when the lower row of steel pipes are constructed one by one, steel brackets are arranged between each lower row of steel pipes and the corresponding tunnel face retaining piles 2 for fixation, and in step 4, they are removed when several tunnel face retaining piles 2 are cut off.

[0062] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A construction method for a face support structure for a pipe-roof top pipe group excavation well, which is arranged in the pipe-roof excavation working well, corresponding to the side wall of an underground structure (9) to be constructed; characterized in that: It comprises an excavation face (1) formed by a plurality of face retaining piles (2) evenly distributed in the horizontal direction; An upper pipe curtain (3) and a lower pipe curtain (6) are respectively arranged above and below the underground structure (9) to be constructed; the upper pipe curtain (3) comprises a plurality of upper steel pipes; the lower pipe curtain (6) comprises a plurality of lower steel pipes; The plurality of upper row steel pipes, the plurality of lower row steel pipes and the plurality of tunnel face retaining piles (2) correspond to each other; The position near the upper end and the position near the middle of the tunnel face (1) are respectively connected to the upper row of pipe curtains (3) and the lower row of pipe curtains (6), that is, the position near the upper end and the position near the middle of each tunnel face retaining pile (2) are respectively connected to the corresponding upper row of steel pipes and the corresponding lower row of steel pipes; The exposed ends of the plurality of upper row steel pipes and the exposed ends of the plurality of lower row steel pipes are welded with steel plates to form steel pipe curtain pipe openings (7); The steps of the construction method are as follows: Step 1, excavating the pipe-roof excavation working shaft to the first excavation surface for constructing the tunnel face retaining piles (2), and constructing all the tunnel face retaining piles (2) of the excavation tunnel face (1); Step 2, excavating the pipe-roof excavation working pit to the second excavation face for constructing the upper row of pipe-roofs (3); cutting off each of the face retaining piles (2) near the upper end, at a position for setting the upper row of pipe-roofs (3); and completing the setting of the corresponding upper row of steel pipes at the position where each of the face retaining piles (2) was cut off near the upper end, thereby completing the construction of the upper row of pipe-roofs (3); Step 3, after the construction of the upper row of pipe curtains (3) is completed, the pipe curtain excavation working shaft is continued to be excavated to the fourth excavation face for constructing the lower row of pipe curtains (6); each of the tunnel face retaining piles (2) is cut off near the middle, where the position for setting the lower row of pipe curtains (6) is located; and the corresponding lower row of steel pipes are set at the position where each of the tunnel face retaining piles (2) is cut off near the middle, thereby completing the construction of the lower row of pipe curtains (6); Step 4: After the construction of the upper pipe curtain (3) and the lower pipe curtain (6) is completed, a number of the tunnel face retaining piles (2) are cut off as required, the excavation tunnel face (1) is opened, and the construction of the underground structure (9) is completed.

2. The construction method for the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 1 is characterized in that: A steel bracket (4) is provided between each of the tunnel face retaining piles (2) and the corresponding upper row of steel pipes and the corresponding lower row of steel pipes.

3. The construction method for the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 2 is characterized in that: Each of the steel brackets (4) comprises two steel plates (8) which are vertically arranged and parallel to each other; An arc-shaped connecting steel plate (9) is provided at one end of the two steel plates (8); and the portions between the two steel plates (8) close to the other ends are connected by a horizontally arranged angle steel (10).

4. The construction method for the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 3 is characterized in that: The arc-shaped connecting steel plate (9) of each of the steel brackets (4) is connected to the corresponding steel pipe curtain pipe opening (7) by welding; The two steel plates (8) of each steel bracket (4) are connected to the corresponding embedded steel plates (11) on the side walls of the face retaining piles (2) by welding.

5. The construction method of the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 1 is characterized in that: For a relatively deep foundation pit with a depth exceeding 10 m, an inclined brace (5) is provided on the side of the excavation face (1) facing the pipe curtain excavation working shaft.

6. The construction method of the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 1 is characterized in that: In step 2, when the upper row of steel pipes are constructed one by one, a steel bracket (4) is arranged between each of the upper row of steel pipes and the corresponding face retaining pile (2) for fixation, and in step 4, when a number of face retaining piles (2) are cut off, they are removed.

7. The construction method of the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 1 is characterized in that: For a deeper foundation pit with a depth exceeding 10 m, between step 2 and step 3, when the pipe curtain excavation working shaft is excavated to the third excavation surface, an inclined brace (5) is added.

8. The construction method of the tunnel face support structure for a pipe-roof top pipe group tunneling well according to claim 1 is characterized in that: In step 3, when the lower row of steel pipes are constructed one by one, a steel bracket (4) is arranged between each lower row of steel pipes and the corresponding face retaining pile (2) for fixation, and in step 4, when a number of face retaining piles (2) are cut off, they are removed.

Images