CN108445185A - One kind can opening door multifunctional tunnel Excavation simulation threedimensional model testing stand - Google Patents

Abstract

The invention discloses an openable three-dimensional tunnel excavation simulation model test box. The model test box is provided with a side door, a central partition and a water inlet pipe network. The side door can be opened and closed conveniently, and at the same time, bolts are used to connect with the model box after closing, which not only facilitates the cleaning of the surrounding rock after the tunnel excavation test, but also ensures the overall rigidity of the model box. The partition plate divides the model box into two small model boxes of the same size, which can be used for three-dimensional tunnel excavation model tests of large and small sizes, especially two small-sized three-dimensional tunnel excavation model tests can be carried out at the same time. After the filling of the surrounding rock is completed, water can be injected into the model box through the water inlet pipe network, and the free liquid level in the surrounding rock can be controlled at the test design position. The model box can be used to complete the three-dimensional tunnel excavation model test under complex conditions such as saturated strata, unsaturated stratum surrounding rock conditions, different buried depths, and different excavation face forms.

Description

A three-dimensional model test bench for multifunctional tunnel excavation simulation with openable doors

technical field

An openable three-dimensional tunnel excavation simulation model test box belongs to the technical field of shield tunneling simulation.

Background technique

The geomechanics model test method is an effective method for studying tunnel excavation problems. It can truly reflect the relationship between geological conditions and engineering structures, and accurately simulate the construction process and impact. The test results are more intuitive and make it easier for people to Grasp the overall mechanical characteristics, deformation trend and stability characteristics of tunnel engineering from an overall perspective, so as to make judgments. Therefore, the research on the tunnel excavation simulation model test platform is very necessary. Yong-Joo Lee (2006) developed a tunnel excavation model test platform with a size of 1.058m×0.93m×0.075m (width×height×thickness). The device simulates the tunnel excavation process, which can be used to study the influence of stratum loss on surrounding rock deformation and adjacent buildings during tunnel excavation; Shandong University (2008) developed a model test platform that can simulate high ground stress tunnel excavation, with a size of 4.5 m×3.55m×2m (width×height×thickness), can realize four-sided loading, and can simulate a maximum buried depth of 2000m. The test bench can realize uniform step loading, simulate the real initial stress field, and conduct high stress and overload damage simulation tests ; Beijing Jiaotong University (2010) developed a plane strain model test platform for tunnel excavation, with a size of 3m × 1.62m × 0.3m, which can be used to study the failure process of tunnel surrounding rock during step-by-step loading; Tongji University (2013) developed A plane strain tunnel excavation model test platform is established, with a size of 1.6m×1.3m×0.4m (width×height×thickness). The excavation system consists of four steel plates and internal support bolts. , which can be used to study the failure process of tunnel surrounding rock during step-by-step loading; Beijing University of Technology (2014) developed a tunnel excavation model test platform with a size of 1.5m×1.5m×0.4m (width×height×thickness), The airbag is used to simulate the process of tunnel excavation, which can be used to study the influence of formation loss on surrounding rock deformation and adjacent buildings during tunnel excavation. The above-mentioned test platforms can only simulate two-dimensional tunnel excavation tests, and cannot conduct research on the three-dimensional spatiotemporal force and deformation laws of surrounding rock and structures during tunnel excavation. Shandong University (2007) developed a new combined three-dimensional geomechanics model test bench device with a size of 4×3.2m×1.7m (width×height×thickness). The three-dimensional model test can also carry out the plane model test, and at the same time, it can simulate the actual terrain and landform characteristics of geotechnical engineering; Jong-Ho Shin (2008), developed a large-scale three-dimensional tunnel excavation simulation test platform with a size of 3.6m×4m× 3.3m, the tunnel excavation diameter can reach 1.1m, can realize top loading, and can conduct research on the stability of surrounding rock and excavation surface in tunnel engineering; Shandong University (2013) developed a fluid-solid coupling model test system for subsea tunnels, The size is 3.4m×3m×0.8m. The test system is easy to assemble, has good sealing performance, and is visualized. The size and structure of the model test frame can be expanded vertically, and large-scale three-dimensional fluid-solid coupling model tests can be carried out. The maximum depth of seawater that can be simulated is 57m. According to different research problems, in recent years, various universities and research institutes have developed a large number of three-dimensional tunnel excavation model test platforms, but it is difficult to clean the surrounding rock materials inside the frame after the tunnel excavation test is completed. There is a common problem. Therefore, it is necessary to develop a multifunctional model test bench that can realize tunnel excavation simulation under different conditions and facilitate the cleaning of surrounding rock materials after the test is completed.

Contents of the invention

The purpose of the present invention is to provide an openable three-dimensional tunnel excavation simulation model test box, which can not only carry out three-dimensional tunnel excavation model test under complex conditions, but also can conveniently clean the surrounding rock materials inside the bench after the test is completed. .

In order to achieve the above object, the present invention adopts the following technical solutions:

A door-openable three-dimensional tunnel excavation simulation model test box, the model test box consists of a base (1), a bottom plate (2), a box wall a (3), a box wall b (4), a box wall c (5), Box wall d (6) is made up of five parts. Box wall a(3), box wall b(4), box wall c(5), box wall d(6) are sequentially connected to form a cuboid structure; box wall (4)b and box wall d(6) are respectively set Reserve the excavation hole (7) and the back reservation excavation hole (8) before. Box wall c (5) is made up of two side doors (9) that can switch, and side door (9) can rotate around the hinge (10) that is installed on both sides, thereby realizes the switch of side door (9). A circle of steel beams (11) is set on the inner side of the box wall c(5). In order to ensure the strength of the box wall c(5) in the test, the two side doors (9) are fixed on the steel beams (11) with high-strength bolts (12). . A partition (13) is installed at the central position of the box wall a (3) and the box wall c (5). After the partition (13) is installed, the model test box of the cuboid structure is divided into two small model boxes of the same size. The partition (13) is fixed on the box wall a (3) and the box wall c (5) through the card slot (14), and the partition (13) can be disassembled freely. In order to ensure the strength of the dividing plate (13) during the test, the dividing plate (13) is fixed on the draw-in groove (14) with bolts. The dividing plate (13) is provided with an excavation hole (16), and the diameter of the excavation hole (16) is equal to the diameter of the front reserved excavation hole (7) and the rear reserved excavation hole (8).

Two sets of independent water inlet pipe networks (17, 18) are installed on the model box bottom plate (2), and the two sets of independent water inlet pipe networks respectively saturate the surrounding rocks in the two small model boxes by the clapboard (13) . Each set of water inlet pipe network (17, 18) is made up of water inlet (19), main pipe (20) and branch pipe (21). Water inlet (19) is drawn by the bottom of case wall (3). A pair of water outlet holes (22) are arranged every 100mm on the branch pipe (21), and the connection line between the two water outlet holes (22) and the center of the branch pipe (21) is orthogonal and arranged symmetrically.

When carrying out the large model test, the dividing plate (13) is disassembled, and the dividing plate (13) is moved out to the outside of the model test box with a crane through the hoisting hole (23) on the upper part of the dividing plate (13). When carrying out small model test, dividing plate (13) is installed in the inside of model test box again.

A sealing ring is provided at the connection between the side door (9) and the steel beam (11), and a sealing ring is also provided at the connection between the partition plate (13) and the slot (14). The gap between the side door (9) and the steel beam (11) The position is sealed with sealant, so that the model test box has good airtightness. Transparent plexiglass is installed on the side door (9), and the variation of the water level in the model test chamber can be observed.

Branch pipe (21) is fixed on the model box bottom plate (2) by steel clamp (24).

Work process and working principle of the present invention are:

Before the test started, the two doors were closed and bolted to the steel beam, and the front and rear excavation holes were closed at the same time. If a large model test is carried out, the partition is lifted out from the inside of the model box. Spread a layer of gravel on the bottom of the model box first to ensure that the water inlet pipes at the bottom can be completely covered to prevent the pipe outlet holes from being blocked during the filling process. Then fill the model box with soil according to the soil filling scheme. The soil body is embedded with earth pressure cells, piezometers and displacement meters, and these sensors are connected with data acquisition and processing devices. After the filling of the surrounding rock is completed, water is injected into the water inlet pipe network at the bottom of the model box, and the free liquid surface is controlled to reach the position designed for the test. Remove the front excavation hole baffle for tunnel excavation, and collect and record various data. After the test is completed, all the fixing bolts of the side door are removed, the side door is opened, and the surrounding rock material inside the model box is taken out. If a small model test is carried out, install the partition in the middle of the model box and repeat the above process.

The beneficial effects of the present invention are:

(1) The tunnel excavation simulation model test bench can complete the three-dimensional tunnel excavation model test under complex conditions such as saturated stratum, unsaturated stratum surrounding rock conditions, and different excavation face forms;

(2) The tunnel excavation simulation model test bench can carry out three-dimensional tunnel excavation model tests of large and small sizes, especially two small-sized three-dimensional tunnel excavation model tests can be carried out at the same time;

(3) The tunnel excavation simulation model test bench opens the side door after the test is completed, which can facilitate the cleaning of surrounding rock materials in the model box.

Description of drawings

Fig. 1 is three-dimensional view of tunnel excavation simulation model box of the present invention;

Fig. 2 is the tunnel excavation simulation model box water inlet pipe network layout diagram of the present invention;

Fig. 3 is a design drawing of outlet holes of branch pipes of the water inlet pipe network according to the present invention.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

As shown in Figures 1 to 3, a door-openable multifunctional tunnel excavation simulation three-dimensional model box according to the present invention

Two fan side doors (9) are closed earlier before the test begins, and it is fixed on the steel beam (11) with bolt (12), and front and rear excavation holes (7,8) are closed simultaneously. If carrying out the large-scale model test, the dividing plate (13) is hung out from the inside of the model box (1). Pave a layer of gravel at the bottom of the model box (1) earlier to ensure that the pipe network (17, 18) at the bottom can be fully covered to prevent the pipe outlet hole from being blocked in the soil filling process. Then fill the model box with soil according to the soil filling scheme. The soil body is embedded with earth pressure cells, piezometers and displacement meters, and these sensors are connected with data acquisition and processing devices. After the filling of the surrounding rock is completed, water is injected into the model box to make the position of the free liquid surface in the surrounding rock meet the test requirements. The baffle plate of the front excavation hole (7) is removed for tunnel excavation, and various data are collected and recorded. After the test was completed, the fixing bolts (12) of the side door were all taken off, the side door (9) was opened, and the surrounding rock material inside the model box was taken out. If the small model test is carried out, the partition plate (13) is installed in the slot (14) in the middle of the model box, and fixed with bolts, and the above test process is repeated. If two small model tests are carried out simultaneously, surrounding rocks are filled in two small model boxes separated by dividing plates (13) simultaneously, and excavation holes (7,8) are reserved for excavating tunnels from the front and back.

Claims (6)

1. one kind can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：The model test box is by pedestal (1), bottom plate (2), tank wall a (3), tank wall b (4), tank wall c (5), (6) five parts tank wall d composition；Tank wall a (3), tank wall b (4), Tank wall c (5), tank wall d (6) are sequentially connected with composition rectangular parallelepiped structure；It is reserved before being respectively set on tank wall (4) b and tank wall d (6) to open Borehole (7) and rear reserved excavation hole (8)；Tank wall c (5) is made of two side doors (9) that can switch of fan, and side door (9) can be around being installed on The hinge (10) of both sides rotates, to realize the switch of side door (9)；One circle girder steel (11) of setting on the inside of tank wall c (5), to ensure Two fan side doors (9) are fixed on girder steel (11) by the intensity of tank wall c (5) in experiment with high-strength bolt (12)；Tank wall a (3) and case The central position of wall c (5) is equipped with partition board (13), and the model test box of rectangular parallelepiped structure is divided into two after partition board (13) installation The identical mini Mod case of a size；Partition board (13) is fixed on tank wall a (3) and tank wall c (5), partition board (13) energy by card slot (14) Enough it is freely disassembled；For the intensity of partition board during guarantee test (13), partition board (13) is fixed on card slot (14) with bolt；Every It is provided on plate (13) and excavates hole (16), the diameter of excavation hole (16) reserved excavation hole (8) with preceding reserved excavation hole (7) and afterwards Diameter is equal.

2. one kind according to claim 1 can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：Mould Two sets of independent water inlet pipe networks (17,18) are installed, two sets of independent water inlet pipe networks are respectively to by partition board on molding box bottom plate (2) Country rock in (13) two mini Mod casees is saturated；Grid (17,18) is often packed by water inlet (19), manifold (20) and branch Manage (21) composition；Water inlet (19) is drawn by tank wall (3) bottom；A pair of of apopore (22) is set every 100mm on branch pipe (21), Two apopores (22) are orthogonal with the line in branch pipe (21) center of circle, and are arranged symmetrically.

3. one kind according to claim 1 can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：Into Partition board (13) are dismantled when row large-sized model is tested, are removed partition board (13) with crane by the hole for hoist (23) on partition board (13) top To the outside of model test box；Partition board (13) is mounted on to the inside of model test box again when carrying out mini Mod experiment.

4. one kind according to claim 1 can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：Side The position setting sealing ring that door (9) is connect with girder steel (11), the position that partition board (13) is connect with card slot (14) are also provided with sealing ring, The position in the gap between side door (9) and girder steel (11) is sealed with fluid sealant, and model test box is made to have good leakproofness； Side door installs transparent organic glass on (9), can observe the variation of water level in model test box.

5. one kind according to claim 1 can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：Branch Pipe (21) is fixed on by steel clamp (24) on model casing bottom plate (2).

6. one kind according to claim 1 can opening door three-dimensional tunnel Excavation simulation model test box, it is characterised in that：Examination It tests before beginning and first closes two fan doors, be fixed on girder steel with bolt, while forward and backward excavation hole being closed；If carrying out Large-sized model is tested, and partition board is hung out inside model casing；First model casing bottom tile one layer of gravel, guarantee by bottom into Waterpipe all covers, and pipeline during banketing is prevented to be discharged hole plug；Then by the scheme of banketing to banketing inside model casing, soil It is embedded with soil pressure cell, osmometer and displacement meter in vivo, these sensors are connected with data acquisition and processing unit；Country rock fills The water filling into the water inlet pipe network of model casing bottom after completion, control free surface reach the position of experimental design；By preceding excavation hole Baffle removes carry out tunnel excavation, and each item data of acquisition and recording；After the completion of experiment, the fixing bolt of side door is all removed, Side door is opened, the country rock material inside model casing is taken out；If carrying out mini Mod experiment, partition board is mounted in model casing Portion repeats the above process.