Super-high backfill open-cut structure with enhanced lateral constraints and its construction method

Abstract

The present invention discloses a super-high backfill open hole structure with enhanced lateral constraints and a construction method thereof. The super-high backfill open hole structure comprises an open hole, the open hole comprises a side wall and an arch ring, backfill soil is backfilled above the open hole, side slopes are arranged on both sides of the side wall, a horizontal column is connected between the side wall and the side slope, one end of the horizontal column extends into the side slope, and the other end extends out of the side slope and is connected to the side wall; the construction method is to horizontally excavate tunnels from the side walls on both sides of the open hole to the side slope respectively; backfill concrete into the tunnel to form a horizontal column, extend the horizontal column out of the side slope and press against the side wall. The present invention extends the horizontal column into the side slope, and provides a sufficiently large reaction force to the horizontal column through the friction resistance of the side slope to act on the side wall of the open hole, and the reaction force is sufficient to balance the vertical force of the backfill soil above the open hole, so that the backfill soil above the arch ring of the open hole can be backfilled with more than 15m, changing the passive situation that it is difficult to build super-high backfill open holes in previous projects.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, in particular to a super-high backfill open-cut structure with enhanced lateral constraints and a construction method thereof. Background Art

[0002] Open-cut structures are subject to great vertical forces, which are mainly determined by the thickness of the backfill soil above the arch ring of the open-cut structure. The forces on the open-cut structure are different from those on blind tunnels. The disadvantage of open-cut structures is that the side walls on both sides cannot provide a large enough reaction force to balance the vertical force generated by the weight of the backfill soil. This results in that when the backfill soil and rocks are too thick and the vertical force is too large, it is very easy to cause fracturing on the inner side of the arch ring concrete, affecting the use of the structure. Therefore, in the past, the design of open-cut structures required that the thickness of the backfill soil and rocks above the arch ring should not exceed 3m. However, it is often encountered in engineering projects that the open-cut structure is required to be filled to the surface because the ground surface is not allowed to sink or the slope expansion soil is difficult to protect. This results in an ultra-high backfill open-cut structure with a backfill thickness of more than 15m. For example Figure 1 As shown, in the super-high backfill open hole structure, the method of arranging backfill concrete 4 on both sides of the side wall 3 of the open hole 1 to increase the reaction force of the side wall 3 is often adopted in the past. However, the contact surface between the backfill concrete 4 and the slope 5 is still a weak surface, and the reaction force of the side wall 3 that can be provided is still not enough to balance the vertical force of the backfill soil 2 above, so that a passive situation occurs in which it is difficult to build a super-high backfill open hole in engineering. Summary of the invention

[0003] The purpose of the present invention is to provide a super-high backfill open hole structure with enhanced lateral constraints and a construction method thereof in view of the problems existing in the prior art.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A super-high backfill open hole structure with enhanced lateral constraints comprises an open hole, wherein the open hole comprises a side wall and an arch ring, backfill soil is backfilled above the open hole, side slopes are arranged on both sides of the side wall, and a cross column is connected between the side wall and the side slope, the cross column is arranged along the horizontal direction of the open hole, one end of the cross column extends into the side slope, and the other end extends out of the side slope and is connected to the side wall.

[0006] The present invention creatively extends the horizontal column into the slope, and provides the horizontal column with a sufficiently large reaction force to act on the side wall of the open hole through the friction resistance of the slope. The reaction force is sufficient to balance the vertical force of the backfill soil above the open hole, so that more than 15m of backfill soil can be backfilled above the arch ring of the open hole, changing the passive situation in previous projects that it is difficult to build ultra-high backfill open holes.

[0007] As a preferred solution of the present invention, the length of the horizontal column extending into the slope is greater than or equal to 6m to ensure that sufficiently large friction resistance is provided.

[0008] As a preferred solution of the present invention, the transverse columns are arranged at intervals along the longitudinal direction of the open hole to ensure that sufficiently large friction resistance is provided.

[0009] As a preferred solution of the present invention, one end of the horizontal column is fixed to the slope, and the other end is pressed against the side wall.

[0010] As a preferred solution of the present invention, the horizontal column is a concrete member, which is easy to construct.

[0011] A construction method for a super-high backfill open hole structure with enhanced lateral constraints comprises the following steps:

[0012] Step 1: Dig tunnels horizontally from the two side walls of the open hole toward the slope;

[0013] Step 2: Backfill concrete into the tunnel to form a horizontal column, extend the horizontal column out of the slope and press against the side wall.

[0014] The existing construction method can quickly complete the excavation of the slope tunnel, and then simply backfill concrete to connect the tunnel side wall and the slope. The friction resistance in the tunnel provides a large enough reaction force for the horizontal column to act on the side wall of the open hole, so as to realize the construction of the ultra-high backfill open hole. The whole construction method has simple procedures, low cost and good effect.

[0015] As a preferred solution of the present invention, a plurality of the tunnels are excavated at intervals along the longitudinal direction of the open hole, and the transverse columns are respectively installed to ensure that sufficiently large friction resistance is provided.

[0016] As a preferred solution of the present invention, the diameter of the tunnel is 2m-4m to ensure that sufficiently large friction resistance is provided.

[0017] As a preferred solution of the present invention, the depth of the tunnel is greater than or equal to 6 m to ensure that sufficiently large friction resistance is provided.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] The present invention creatively extends the horizontal column into the slope, and provides the horizontal column with a sufficiently large reaction force to act on the side wall of the open hole through the friction resistance of the slope. The reaction force is sufficient to balance the vertical force of the backfill soil above the open hole, so that more than 15m of backfill soil can be backfilled above the arch ring of the open hole, changing the passive situation in previous projects that it is difficult to build ultra-high backfill open holes. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional view of backfilling concrete on both sides of the open hole as described in the background technology.

[0021] Figure 2It is a cross-sectional view of the super-high backfill open hole structure with enhanced lateral constraints described in the present invention.

[0022] Figure 3 It is a longitudinal section diagram of the super-high backfill open hole structure with enhanced lateral constraints described in the present invention.

[0023] Figure 4 It is a structural schematic diagram of the excavated tunnel described in the present invention.

[0024] Icons: 1-open hole, 2-backfill soil, 3-side wall, 4-backfill concrete, 5-slope, 6-horizontal column, 61-horizontal column inside the hole, 62-horizontal column outside the hole, 7-tunnel. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] Example 1

[0028] like Figure 2 As shown, a super-high backfill open hole structure with enhanced lateral constraints includes an open hole 1, the open hole 1 includes a side wall 3 and an arch ring, backfill soil 2 is backfilled above the open hole 1, and side slopes 5 are arranged on both sides of the side wall 3. A concrete horizontal column 6 is connected between the side wall 3 and the side slope 5, and the diameter of the horizontal column 6 is 2m-4m and the length is about 10m. The horizontal column 6 consists of two parts, one is an in-hole horizontal column 61 extending into the side slope 5 and consolidating with the side slope 5, and the length of the in-hole horizontal column 61 is about 6m, and the other is an out-hole horizontal column 62 extending out of the side slope 5 and pressing against the side wall 3.

[0029] like Figure 3 As shown, a plurality of the transverse columns 6 are arranged at intervals along the longitudinal direction of the open hole 1 .

[0030] Example 2

[0031] A construction method for a super-high backfill open hole structure with enhanced lateral constraints comprises the following steps:

[0032] Step 1: If Figure 4 As shown, tunnels 7 are excavated horizontally from the side walls 3 on both sides of the open hole 1 to the slope 5, and the diameter of the tunnel 7 is 2m-4m and the depth is about 6m;

[0033] Step 2: If Figure 2As shown, concrete is backfilled into the tunnel 7 to form a horizontal column 6 (a horizontal column 61 inside the tunnel), and the horizontal column 6 is extended out of the slope 5 and pressed against the side wall 3 (a horizontal column 62 outside the tunnel).

[0034] Step 3: Repeat steps 1 to 2. Figure 3 As shown, a plurality of tunnels 7 are excavated at intervals along the longitudinal direction of the open hole 1, and the cross pillars 6 are respectively constructed.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A super-high backfill open hole structure with enhanced lateral constraints, comprising an open hole (1), the open hole (1) comprising a side wall (3) and an arch ring, backfill soil (2) is backfilled above the open hole (1), and side slopes (5) are arranged on both sides of the side wall (3), characterized in that: A transverse column (6) is connected between the side wall (3) and the side slope (5), one end of the transverse column (6) extends into the side slope (5), and the other end extends out of the side slope (5) and is connected to the side wall (3), the length of the transverse column (6) extending into the side slope (5) is greater than or equal to 6m, and the transverse columns (6) are arranged at intervals along the longitudinal direction of the open hole (1).

2. The super-high backfill open hole structure with enhanced lateral constraints according to claim 1 is characterized in that: One end of the horizontal column (6) is fixed to the side slope (5), and the other end is pressed against the side wall (3).

3. The super-high backfill open-cut structure with enhanced lateral constraints according to any one of claims 1-2, characterized in that: The cross column (6) is a concrete component.

4. A construction method for a super-high backfill open hole structure with enhanced lateral constraints, characterized in that: The construction of the super-high backfill open-cut structure with enhanced lateral constraints as described in any one of claims 1 to 3 comprises the following steps: Step 1: excavating tunnels (7) from the side walls (3) on both sides of the open hole (1) toward the slope (5); Step 2: backfilling concrete into the tunnel (7) to form a horizontal column (6), extending the horizontal column (6) out of the slope (5) and pressing against the side wall (3).

5. The construction method of a super-high backfill open hole structure with enhanced lateral constraints according to claim 4 is characterized in that: A plurality of tunnels (7) are excavated at intervals along the longitudinal direction of the open hole (1), and the transverse columns (6) are respectively constructed.

6. The construction method of a super-high backfill open hole structure with enhanced lateral constraints according to claim 4 is characterized in that: The diameter of the tunnel (7) is 2m-4m.

7. The construction method of a super-high backfill open hole structure with enhanced lateral constraints according to claim 4 is characterized in that: The depth of the tunnel (7) is greater than or equal to 6 m.

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