CN214787438U

CN214787438U - Temporary supporting structure for tunneling tunnel portal of hilly soil layer

Info

Publication number: CN214787438U
Application number: CN202120157072.2U
Authority: CN
Inventors: 杨康; 钱永; 边伟民; 袁登; 李烨棋; 姚银威; 严龙龙; 诸葛挺; 张志炳; 陈江宏
Original assignee: Zhejiang Communications Construction Group Co Ltd
Current assignee: Zhejiang Communications Construction Group Co Ltd
Priority date: 2021-01-20
Filing date: 2021-01-20
Publication date: 2021-11-19
Anticipated expiration: 2031-01-20

Abstract

The utility model provides a temporary supporting structure for tunneling a tunnel portal of a hillside soil layer, which comprises an arch-shaped support which is arranged along the circumferential direction of the inner wall of a tunnel and is formed by connecting a plurality of I-shaped steel sections end to end, wherein the bottom of the arch-shaped support and the connection part of the side edges of the arch-shaped support are provided with brackets, and the bottom of each bracket is fixedly connected with a steel plate which is arranged vertically; the bracket top all disposes lock foot little pipe group, lock foot little pipe group's one end and arch support fixed connection, the other end extends towards the oblique below in the outside of arch support circumference. The temporary supporting structure can effectively solve the problem of primary settlement in the construction of the tunnel portal of the cohesive soil layer with residual slope.

Description

Temporary supporting structure for tunneling tunnel portal of hilly soil layer

Technical Field

The utility model relates to an interim bearing structure of tunnel tunnelling in-process, specifically speaking relates to an interim bearing structure that is used for hillside soil layer tunnel entrance to a cave to tunnel tunnelling.

Background

In the construction of tunnel portal with cohesive soil gravel layer in residual slope, after the primary support of the upper step is completed, the phenomena of continuous exceeding of early warning value of settlement in the tunnel, serious settlement of the earth surface outside the tunnel and the like often occur. At present, the tunnel portal construction of the residual slope soil accumulation layer generally adopts a mode of reinforcing soil by earth surface grouting to achieve the purpose of stabilizing the soil at the portal. However, because the permeability of cohesive soil is poor, the grouting effect is not good, and the residual slope soil deposit layer is difficult to be integrated through grouting. The problem of primary support settlement still can not be solved when the tunnel portal is constructed. How to effectively control the primary settlement in the construction of the tunnel portal containing the cohesive soil crushed stone layer in the residual slope is a great technical problem at present.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model aims at providing a temporary support structure for tunneling of hillside soil layer tunnel entrance to a cave, this bearing structure can effectively solve the construction of incomplete hillside soil layer cohesive soil layer tunnel entrance to a cave and just prop up the settlement problem.

Based on the purpose, the utility model provides a temporary supporting structure for the excavation of a tunnel portal of a hillside soil layer, which comprises an arch support which is arranged along the circumferential direction of the inner wall of a tunnel and is formed by connecting a plurality of I-shaped steel sections end to end, wherein the bottom of the arch support corresponding to an upper step and a middle step of the tunnel construction is respectively provided with a bracket, and the bottom of the bracket is fixedly connected with a steel plate which is vertically arranged with the bracket; the bracket top all disposes lock foot little pipe group, lock foot little pipe group's one end and arch support fixed connection, the other end extends towards the oblique below in the outside of arch support circumference.

Preferably, the bracket is symmetrically cut by I18I-steel along the long edge and is fixed with the arch support in a manner of full-face welding.

Preferably, the steel plate has a side length of not less than 200mm and a thickness of not less than 12 mm.

Preferably, the small lock pin guide pipe group comprises a pair of small lock pin guide pipes which are arranged in parallel, and the small lock pin guide pipes are welded and fixed with the arch-shaped support through a U-shaped rib.

Preferably, the U-shaped rib is formed by bending a steel bar with the diameter not less than 15 mm.

Preferably, the length of the small lock pin guide tube is not less than 3m, the diameter of the small lock pin guide tube is not less than 35mm, and the tube hole of the small lock pin guide tube is filled with mud.

Preferably, the temporary supporting structure further comprises a temporary inverted arch, and two ends of the temporary inverted arch are respectively and fixedly connected with two ends of the bottom of the arch support, so that the temporary inverted arch and the arch support are closed to form a ring to support the inner wall of the tunnel.

Preferably, the arch support and the temporary inverted arch are both made of I18I-shaped steel.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses an add in the arch-shaped support bottom and establish bracket and steel sheet, increase the area of contact of arch-shaped support bottom and ground, add respectively in the middle part of arch-shaped support direction of height and bottom simultaneously and establish oblique downward, the little pipe group of lock foot of outside extension, further support and fix arch-shaped support, make this arch-shaped support abundant and tunnel inner wall laminating, thereby further increase the area of contact of arch-shaped support and tunnel inner wall, effectively solve incomplete slope area stickness soil layer tunnel entrance to a cave construction first settlement problem.

Furthermore, the utility model discloses an among the embodiment, still connect interim invert in arched support bottom, this interim invert seals with arched support and encircles and supports the tunnel inner wall, has strengthened this interim bearing structure's support intensity further.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.

Fig. 1 is a schematic overall structure diagram of an embodiment of the present invention;

FIG. 2 is a schematic view of the connection at A in FIG. 1;

FIG. 3 is a schematic view of the connection at B in FIG. 1;

fig. 4 is one of the schematic views of the installation structure of the small conduit group of the lock pin in the embodiment of the present invention;

fig. 5 is a second schematic view of the installation structure of the locking small tube set in the embodiment of the present invention.

Wherein, 1, an arch support; 2. a temporary inverted arch; 3. a locking pin small conduit group; 4. a bracket; 5. u-shaped ribs; 6. an upper step; 7. a middle step; 8. and (3) a steel plate.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The embodiment provides a temporary supporting structure for tunneling a tunnel portal of a hilly soil layer, which comprises an arch support 1, a steel plate 8 and a bracket, wherein the arch support 1 is arranged along the circumferential direction of the inner wall of a tunnel and is formed by connecting a plurality of I-shaped steel sections end to end, brackets 4 are respectively arranged at the bottoms of an upper step 6 and a middle step 7 of tunnel construction, and the bottoms of the brackets 4 are fixedly connected with the steel plate 8 which is vertically arranged with the brackets as shown in fig. 3; all dispose lock foot little pipe group 3 above the bracket 4, lock foot little pipe group 3's one end and arched bracket 1 fixed connection, the other end extends towards the oblique below in the arched bracket 1 circumference outside. Thus, when the preliminary bracing of the upper step 6 and the middle step 7 is carried out, the bracket 4 is welded at the bottom of the arch support 1 to increase the contact area between the bottom of the arch and the ground foundation.

As a better embodiment, the bracket 4 is symmetrically cut from I18I-steel along the long edge and is fixed with the arched bracket 1 by full welding. Specifically, the preferred practice of the corbel 4 is: the same I18I-steel as the primary arch support 1 is used, and is symmetrically cut into a triangular structure along the long edge, preferably, the width of the bottom is 18cm, the height of the bottom is 54cm, and the long edge of the right angle is in full welding with the arch center back. The bracket 4 has the functions of increasing the contact area between the arched bracket 1 on the upper step and the arched bracket on the middle step 7 and the foundation, reducing the pressure intensity and reducing the sedimentation rate when the primary support is not closed into a ring.

In a preferred embodiment, the steel plate 8 has a side length of not less than 200mm and a thickness of not less than 12mm, and preferably, the steel plate 8 has a specification of 240mm × 240mm × 14 mm.

As a preferred embodiment, as shown in fig. 4 and 5, the locking leg small conduit group 3 comprises a pair of locking leg small conduits which are arranged in parallel and are welded and fixed with the arched bracket 1 through a U-shaped rib 5. Preferably, the U-shaped rib 5 is formed by bending a steel bar with a diameter not less than 15 mm. Further preferably, the length of the locking pin small catheter is not less than 3m, the diameter of the locking pin small catheter is not less than 35mm, and the pipe hole of the locking pin small catheter is filled with mud. Further preferably, the specification of the small conduit of the locking pin is 3.5m + phi 42mm, and the specification of the U-shaped rib is phi 18; and the small pipe groups 3 with locking feet are respectively arranged on two sides of the primary support of the upper step 6 and the middle step 7, the small pipe with the locking feet is welded with the arch frame by using the U-shaped ribs with the specifications, and the small pipe is filled with 1:1 cement paste to increase the strength of the small pipe.

As a preferred embodiment, the temporary supporting structure further includes a temporary inverted arch 2, as shown in fig. 2, both ends of the temporary inverted arch 2 are respectively fixedly connected with both ends of the bottom of the arch support 1, and preferably, after being welded and fixed, the temporary inverted arch 2 and the arch support 1 are further connected by bolts, so that the temporary inverted arch 2 and the arch support 1 are closed to form a ring to support the inner wall of the tunnel. It should be noted that the temporary inverted arch 2 is additionally arranged on the middle step 7 after the primary support is finished, the two ends of the arch support 1 are connected, and concrete is sprayed on the net to enable the primary support to be closed into a ring.

In a preferred embodiment, the arch support 1 and the temporary inverted arch 2 are both made of I18I-shaped steel. Thus, the whole supporting system ensures the safety and stability of the primary support in the residual slope cohesive soil layer by combining the primary bracket 4 and the added small conduit for locking the feet.

To sum up, the utility model discloses an add in the arch-shaped support bottom and establish bracket and steel sheet, increase the area of contact of arch-shaped support bottom and ground, add respectively in the middle part of arch-shaped support direction of height and bottom simultaneously and establish oblique downward, the little pipe group of lock foot of outside extension, further support and fix arch-shaped support, make this arch-shaped support abundant and the laminating of tunnel inner wall to further increase the area of contact of arch-shaped support and tunnel inner wall, effectively solve incomplete slope product stickness soil layer tunnel entrance to a cave construction first settlement problem.

Although the embodiments of the present invention have been shown and described, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments without departing from the spirit and scope of the present invention, and that any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.

Claims

1. A temporary supporting structure for tunneling a tunnel portal of a hilly soil layer comprises an arch support (1) which is arranged along the circumferential direction of the inner wall of a tunnel and is formed by connecting a plurality of I-shaped steel sections end to end, and is characterized in that brackets (4) are respectively arranged at the bottoms of an upper step (6) and a middle step (7) of the arch support (1) corresponding to tunnel construction, and the bottoms of the brackets (4) are fixedly connected with steel plates (8) which are vertically arranged with the brackets; bracket (4) top all disposes lock foot little pipe group (3), the one end and the arched bracket (1) fixed connection of lock foot little pipe group (3), the other end extends towards the oblique below in arched bracket (1) circumference outside.

2. The temporary support structure for tunneling of tunnel portal in hillside soil layer according to claim 1, wherein the corbels (4) are symmetrically cut from I18I-steel along the long edge and are fixed with the arched supports (1) in a manner of full-face welding.

3. The temporary support structure for the tunneling of a pilaster tunnel portal according to claim 2, wherein the steel plate (8) has a side length of not less than 200mm and a thickness of not less than 12 mm.

4. The temporary support structure for tunneling of tunnel portal in hillside soil layer according to claim 1, wherein the small guide tube set (3) comprises a pair of small guide tubes with locking legs arranged in parallel, and the small guide tubes with locking legs are welded and fixed with the arch-shaped support (1) through a U-shaped rib (5).

5. The temporary support structure for the tunneling of the tunnel portal of the hilly soil layer according to claim 4, wherein the U-shaped ribs (5) are formed by bending steel bars with the diameter not less than 15 mm.

6. The temporary support structure for the tunneling of the hilly-soil layer tunnel portal according to claim 4, wherein the length of the small guide tube with the locking leg is not less than 3m, the diameter of the small guide tube with the locking leg is not less than 35mm, and the tube hole of the small guide tube with the locking leg is filled with slurry.

7. The temporary supporting structure for tunneling of the tunnel portal in the hillside soil layer according to claim 1, characterized in that the temporary supporting structure further comprises a temporary inverted arch (2), two ends of the temporary inverted arch (2) are respectively and fixedly connected with two ends of the bottom of the arch support (1), so that the temporary inverted arch (2) and the arch support (1) are closed to form a ring to support the inner wall of the tunnel.

8. The temporary supporting structure for the tunneling of the tunnel portal of the hilly soil layer according to claim 7, wherein the arch-shaped support (1) and the temporary inverted arch (2) are both made of I18I-shaped steel.