WO2020007088A1

WO2020007088A1 - Coupled supporting and protection structure based on high constant-resistance mechanical monolithic support, and construction method therefor

Info

Publication number: WO2020007088A1
Application number: PCT/CN2019/082156
Authority: WO
Inventors: 陈彦龙; 吴鹏; 樊进城; 巨峰; 程绍文; 蒋梦来; 胡继强; 兰东昊; 张亚雪
Original assignee: 中国矿业大学
Priority date: 2018-07-03
Filing date: 2019-04-11
Publication date: 2020-01-09
Also published as: CN108756950A

Abstract

Disclosed are a coupled supporting and protection structure based on a high constant-resistance mechanical monolithic support, and a construction method therefor. The structure comprises a high constant-resistance mechanical monolithic support, an inter-support tie rod (3), an anchor bolt (6), an anchor cable (7) and concrete spray layers (4, 5). The construction process comprises: firstly, digging a tunnel according to design requirements for the tunnel, uniformly spraying a concrete spray layer (4) with a thickness of 50-100 mm onto a cross section of the tunnel, and reinforcing surrounding rock of the tunnel by means of an anchor bolt and cable supporting and protection method; then, installing a high constant-resistance mechanical monolithic support and an inter-support tie rod; and finally, re-spraying a concrete spray layer (5) with a thickness of 30-50 mm to constitute the coupled supporting and protection structure based on the high constant-resistance mechanical monolithic support. The supporting and protection structure has characteristics such as a high self-bearing capacity, good integrity, self-adaption of coordinated deformation with the surrounding rock, and a good effect; and the corresponding construction method is simple and has a high efficiency, thus having an obvious effect and a promotion and application value with regard to control over the surrounding rock of a soft rock tunnel.

Description

Coupling support structure and construction method based on high constant resistance mechanical single support

Technical field

The invention relates to the technical field of soft rock roadway support, in particular to a high-constant-resistance mechanical single-frame coupling support structure and construction method for supporting large deformed soft rock roadways in underground mining or rock engineering.

Background technique

With the shallow depletion of coal resources in China, coal mining gradually extends to the deep at a speed of 10-12m every year, and deep roadways are mostly characterized by soft rock roadways. The problem of support for soft rock roadways has become a problem that plagues coal companies' safe and efficient production. Big problem.

At present, for soft rock roadways, the main support technologies used are anchor shotcrete support technology, anchor mesh shotcrete support technology, prestressed anchor cable support technology, steel frame shed support technology, pressure relief support technology, steel bars Concrete support technology, stone-masonry concrete support technology, etc. In these support technologies, active support such as anchor rods can only act on surrounding rock fractured and plastic areas, which is difficult to play the role of suspension load; passive support such as steel frame sheds have higher costs and input-output The ratio is unreasonable, the stability is poor, and the construction speed is slow. The flexible support structure has a small support strength and cannot effectively control the continuous deformation of the roadway; the rigid support structure has a small support range and it is difficult to form an overall rigid support.

The research results of soft rock roadway support technology show that in the process of controlling and treating soft rock roadways in coal mines, there is an urgent need for a high-strength support resistance to soft rock roadways. The construction is convenient and the support range is large. Surrounding rock deformation and failure of rock roadway, and a better supporting structure.

Summary of the invention

Objective of the invention: In view of the above-mentioned existing technology, a coupling support structure and construction method based on a high constant resistance mechanical single-frame support are provided, and active and passive support of a soft rock roadway is provided at the same time, so that the soft rock roadway can fully release the surrounding rock deformation. Yes, and provide sufficient support to control the surrounding rock deformation of the roadway.

Technical solution: A coupling support structure based on a high-constant-resistance mechanical single-unit support, comprising a number of high-constant-resistance mechanical single-unit supports and inter-rods; the high-constant-resistance mechanical single-unit support includes two circular arc-shaped columns arranged symmetrically above and below. , And two circular arc-shaped poles arranged symmetrically on the left and right sides; the inside of the end of the cylinder is an inverted conical surface, and two ends of the pole are respectively sleeved with the bearing bead frame and extend into the bearing bead frame together with the bearing bead frame. At the end of the cylinder, the cylinder and the pole form a ring-shaped frame structure connected end to end; the plurality of high-constant-resistance mechanical single-unit brackets are arranged coaxially in parallel, and two adjacent single-unit brackets pass through four symmetrical frames along the circumference. The tie rod is fixed.

Further, the inter-frame tie rod comprises a connecting rod and a cylinder clamping collar located at both ends of the connecting rod, and the cylinder clamping collar is clamped on the outside of the cylinder by a bolt and nut and is located at The connection between the pole and the cylinder is described.

A construction method based on a high-constant-resistance mechanical single-bracket coupling support structure includes the following steps:

Step 1: Spray 50-100mm thick concrete spraying layer on the cross section of the roadway;

Step 2: Drive the bolts and cables evenly into the surrounding rock of the roadway; the anchors are high-strength prestressed anchors with a diameter of 20-25mm, a length of 2000-2800mm, and a row spacing of 800 × 800mm The prestress is 60-80kN; the anchor cable is a high-strength prestressed anchor cable with a diameter of 18-22mm, a length of 6000-9000mm, a row spacing of 1000 × 1600mm, and a prestress of greater than 160kN;

Step 3: Install a high-constant-resistance mechanical monolithic bracket. The specific installation steps are as follows: a bearing bead frame is sleeved at each end of the two poles on both sides, and the bearing bead frame is 50-100mm away from the end of the pole, and the two cylinders are placed on the roadway. At the bottom plate, insert the pole and the bearing bead into the upper cylinder, then rotate the connected pole and cylinder axially along the roadway, and connect the lower cylinder with the poles on both sides. Several high-constant-resistance mechanical single-unit brackets are arranged in parallel in parallel, and the distance between two adjacent single-unit brackets is 0.8-1.6m, and they are connected and fixed by four inter-frame tie rods that are symmetrical along the circumference. When inter-frame tie rods are installed, the inter-frame tie rods The cylinder clamping collars on both sides are in an open state. The two leaves surround the adjacent cylinders, insert the clamping bolts into the bolt holes, and clamp with the clamping nuts. The cylinder clamping collars are closed and locked. ;

Step 4: Re-spray 30-50mm thick concrete spray layer to make the concrete spray layer fully contact with the high constant resistance mechanical single support.

Further, each end of the inter-frame tie rod has a cylinder clamping collar, and the cylinder clamping collar is an opening and closing collar. Bolt holes are provided on both sides of each opening and closing collar. Tight bolts and clamping nuts are connected and separated from the bolt holes to control the closing and opening of the cylinder clamping collar, and the inter-frame pull rods are fixed at the joints of the cylinder and cylinder.

Further, the materials of the concrete spray layer in step 1 and step 4 are the same, the mixing ratio is cement: water: sand 1: 2: 2, and the content of the accelerator is 2.6% of the amount of cement.

Beneficial effects: Compared with the prior art, the present invention has advantages and beneficial effects:

(1) The design of anchor rods, anchor cables and sprayed concrete structures forms a flexible support structure in the early stage, which belongs to the category of active support and has a good pressure relief effect.

(2) High-constant resistance mechanical single-element support ring design, which can transfer local pressure to the entire support structure, so that the roadway pressure is evenly distributed throughout the support system. When under pressure, the column rod enters the column cylinder, and the steel ball in the bearing bead frame is used to roll the contact surface of the rod body to deform the contact surface to provide working resistance, forming a flexible and rigid support structure in the later period, which belongs to the passive support category. The combination of first resistance and back resistance, the combination of resistance and resistance allows the surrounding rock deformation to be fully released, effectively alleviating the bearing pressure of the supporting members.

(3) The working resistance of the high constant resistance mechanical single support depends on the material properties of the bearing bead frame and the steel pipe itself. It is not affected by other external factors such as installation and environment, and can make full use of the mechanical strength of the cylinder and the rod itself.

In summary, the present invention provides a support structure and construction method based on a high-constant-resistance mechanical single-frame support coupling, which reflects the support concept of "first lord, then quilt, first quilt, first flexible, rigid, flexible and flexible" , Can make the soft rock roadway fully release the surrounding rock deformation energy, and provide sufficient support to control the roadway surrounding rock deformation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a coupled support structure of a high-constant-resistance mechanical single-body support in an embodiment; FIG.

2 is a schematic view of a structural system of a high-constant-resistance mechanical single-body support in an embodiment;

3 is a schematic structural diagram of an inter-rack tie rod in an embodiment;

FIG. 4 is a schematic view of a bearing bead frame connection structure in the embodiment.

In the picture: 1 cylinder; 2 pillars; 3 inter-rods; 4 initial concrete spraying; 5 late concrete spraying; 6 anchor rods; 7 anchor cables; 8 bearing beads; 9 cylinder clamping collars; 10 Clamping bolt; 11 clamping nut.

detailed description

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

The invention can be better understood based on the following examples. However, those skilled in the art can easily understand that the specific material proportions, process conditions, and results described in the examples are only used to illustrate the present invention, and should not and should not limit the present invention described in detail in the claims. .

A coupling support structure based on a high-constant-resistance mechanical single-unit stent includes a high-constant-resistance mechanical single-unit stent structure system. The high-constant-resistance mechanical single-unit stent structure system is composed of several high-constant-resistance mechanical single-unit stent and inter-frame tie rods, as shown in Figure 2. Show. The high-constant-resistance mechanical single-body support is composed of two circular-arc columns 1 symmetrically arranged up and down, and two circular-arc columns 2 symmetrically arranged left and right. The diameter of the cylinder is larger than the diameter of the pole. The inside of the end of the cylinder 1 is an inverted conical surface. The two ends of the pole 2 are respectively sleeved with the bearing bead frame 8 and protrude into the end of the cylinder 1 with the bearing bead frame 8 as shown in Figure 4. As shown. The cylinder 1 and the pole 2 form a ring-shaped frame structure connected end to end. Several high-constant-resistance mechanical unit brackets are coaxially arranged in parallel, and two adjacent unit brackets are connected and fixed by four inter-frame tie rods 3 that are symmetrical around the circumference.

As shown in FIG. 3, each end of the inter-rack tie rod 3 has a cylinder clamping collar 9 and the cylinder clamping collar 9 is an opening and closing collar. Bolt holes are provided on both sides of each opening and closing collar. Through the connection and separation of the clamping bolt 10 and the clamping nut 11 from the bolt hole, the closing and opening of the cylinder clamping collar 9 is controlled. The cylinder clamping collar 9 is clamped on the outside of the cylinder by a clamping bolt 10 and a clamping nut 11, and an inter-frame tie rod 3 is fixed at the connection between the cylinder 2 and the cylinder 1.

Step 1: According to the design requirements of the roadway, excavate the roadway, spray 50-100mm thick concrete spraying layer 4 on the roadway section, close the exposed surface of the surrounding rock, and provide early flexible support.

Step 2: The anchor rod 6 and the anchor cable 7 are evenly driven into the surrounding rock of the roadway in a radial pattern. Anchor rod 6 is a high-strength prestressed anchor rod with a diameter of 20-25mm, a length of 2000-2800mm, a row spacing of 800 × 800mm, and a prestress of 60-80kN; the anchor cable 7 is a high-strength prestressed anchor cable with a diameter It is 18-22mm, the length is 6000-9000mm, the interval is 1000 × 1600mm, and the prestress is greater than 160kN. The anchor rock 6 and the anchor cable 7 are used to fix the surrounding rock to the deep hard rock mass, and to strengthen the surrounding rock so that the surrounding rock can fully exert its autonomous bearing capacity.

Step 3: Install the high constant resistance mechanical single bracket. The specific installation steps are as follows: a bearing bead holder 8 is sleeved at each end of the pole 2 on both sides, and the bearing bead holder 8 is 50-100 mm away from the end of the pole 2; the two cylinders 1 are placed on the floor of the roadway; the pole 2 Insert the bearing bead frame 8 into the upper column cylinder 1, and then rotate the connected column rod 2 and the column cylinder 1 along the roadway axially at a certain angle, and connect the lower column cylinder 1 with the column rods 2 on both sides.

Several high-constant-resistance mechanical single-unit brackets are arranged in parallel and coaxially, and the distance between two adjacent single-unit brackets is 0.8-1.6m, and they are connected and fixed by four inter-frame tie rods 3 that are symmetrical along the circumference. When installing the inter-frame tie rod 3, the cylinder clamping collars 9 on both sides of the inter-frame tie rod 3 are in an open state, and the two leaves surround the adjacent two cylinders 1. Insert the clamping bolt 10 into the bolt hole and use the clamping nut. 11 clamp, close the cylinder clamping collar 9 and lock it.

Step 4: Re-spray 30-50mm thick concrete spray layer 5 so that the concrete spray layer 5 is in full contact with the high constant resistance mechanical monolithic support to form a soft rock roadway based on the high constant resistance mechanical monolithic support coupling support structure, as shown in Figure 1. .

In the above process, the materials of the concrete spraying layer in step 1 and step 4 are the same, the mixing ratio is cement: water: sand 1: 2: 2, and the content of the accelerator is 2.6% of the cement amount.

Claims

A coupling support structure based on a high constant-resistance mechanical single-body support, which is characterized in that it includes several high-constant-resistance mechanical single-stent supports and inter-rods; the high-constant-resistance mechanical single-unit support includes two arc-shaped columns symmetrically arranged up and down Tube (1), and two circular arc-shaped column rods (2) symmetrically arranged left and right; the inside of the end of the column tube (1) is an inverted conical surface, and two ends of the column rod (2) are respectively sleeved with bearings The bead frame (8) and the bearing bead frame (8) extend into the end of the cylinder (1), and the cylinder (1) and the pole (2) form an endless frame structure connected end to end; the Several high-constant-resistance mechanical single-unit brackets are arranged in parallel and coaxially, and two adjacent single-unit brackets are connected and fixed by four inter-frame tie rods (3) which are symmetrical along the circumference.
The high-resistance-resistance-based mechanical single-coupling coupling support structure according to claim 1, wherein the inter-rack tie rod (3) comprises a connecting rod and a cylinder clamping collar at both ends of the connecting rod ( 9), the cylinder clamping collar (9) is clamped on the outside of the cylinder (1) by a clamping bolt (10) and a clamping nut (11), and is located on the column rod (2) and Attachment of column (1).
A construction method based on a high-constant-resistance mechanical single-frame support and support structure, characterized in that it includes the following steps:

Step 1: Spray 50-100mm thick concrete spray layer on the cross section of the roadway (4);

Step 2: The anchor rod (6) and the anchor cable (7) are evenly driven into the surrounding rock of the roadway; the anchor rod (6) is a high-strength prestressed anchor rod with a diameter of 20-25mm and a length of 2000- 2800mm, row spacing is 800 × 800mm, pre-stress is 60-80kN; the anchor cable (7) is high-strength prestressed anchor cable, diameter is 18-22mm, length is 6000-9000mm, row spacing is 1000 × 1600mm , The prestress is greater than 160kN;

Step 3: Install a high-constant-resistance mechanical single-piece bracket. The specific installation steps are as follows: a bearing bead frame (8) is sleeved on each end of the pole rods (2) on both sides, and the bearing bead frame (8) is away from the pole rod (2). The end is 50-100mm, and the two cylinders (1) are placed on the floor of the roadway. The column (2) and the bearing bead holder are inserted into the upper column (1), and then the connected column (2) and the column (1) ) After axially rotating along the roadway, connect the lower cylinder (1) with the two poles (2) on both sides; several high-constant-resistance mechanical monolithic brackets are coaxially arranged in parallel, and the distance between two adjacent monolithic brackets is 0.8- 1.6m and connected and fixed by four inter-frame tie rods (3) along the circumference; when the inter-frame tie rods (3) are installed, the cylinder clamping collars (9) on both sides of the inter-frame tie rods (3) are in an open state , The two leaves encase the two adjacent cylinders (1), insert the clamping bolt (10) into the bolt hole, and clamp with the clamping nut (11), close and lock the cylinder clamping collar (9) ;

Step 4: Re-spray 30-50mm thick concrete spray layer (5), so that the concrete spray layer (5) is in full contact with the high-constant-resistance mechanical single-body support.
The construction method based on the high constant-resistance mechanical single-stent coupling support structure according to claim 3, characterized in that each end of the inter-frame tie rod (3) has a cylinder clamping collar (9), so that The cylinder clamping collar (9) is an opening and closing collar, and bolt holes are provided on both sides of each of the opening and closing collars. The clamping bolt (10) and the clamping nut (11) are connected with the bolt holes. The connection and separation are used to control the closing and opening of the cylinder clamping collar (9), and the inter-frame tie rod (3) is fixed at the connection between the cylinder and the cylinder.
The construction method based on the high-constant-resistance mechanical single-bracket coupling support structure according to claim 3, characterized in that the material of the concrete spray layer in steps 1 and 4 is the same, and the mixing ratio is cement: water: sand 1 : 2: 2, the content of the accelerator is 2.6% of the cement.