CN109696541B - Three-dimensional model tunnel test device for simulating excavation settlement of tunnel with cavity stratum - Google Patents

Abstract

Translated fromChinese

本发明公开了一种模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，涉及岩土工程中隧道开挖的三维试验模型领域，包括：箱体，用于放置土体；大气囊，通过伸缩装置设置于所述箱体内，用于模拟隧道埋深的变化；风干装置，设置于所述箱体上，用于加速所述箱体内土体风干；数个小气囊，设置于所述箱体的内部，用于形成地层空洞；以及沉降位移测量装置，设置于所述箱体上，用于测量箱体内土体的高度。本发明的有益效果是，可加快箱体内的土风干固结，能够节省大量的试验时间；测量更加便捷简单，且能抵抗外界环境的干扰，精度较高；实现了隧道埋深位置的调整和对比试验；尽可能地减小对周围土体的扰动，最大程度上模拟了真实隧道施工中的工程环境。

The invention discloses a three-dimensional model tunnel test device for simulating tunnel excavation settlement in a stratum containing voids, and relates to the field of three-dimensional test models for tunnel excavation in geotechnical engineering. The telescopic device is arranged in the box to simulate the change of the buried depth of the tunnel; the air drying device is arranged on the box to accelerate the air drying of the soil in the box; several small airbags are arranged in the box The inside of the body is used to form a stratum cavity; and a settlement displacement measuring device is arranged on the box body and used to measure the height of the soil body in the box body. The beneficial effects of the invention are that the soil-air drying and consolidation in the box can be accelerated, and a large amount of test time can be saved; the measurement is more convenient and simple, and can resist the interference of the external environment, and the precision is high; Comparative test; minimize the disturbance to the surrounding soil, and simulate the engineering environment in real tunnel construction to the greatest extent.

Description

Three-dimensional model tunnel test device for simulating excavation settlement of tunnel with cavity stratum

Technical Field

The invention relates to the field of three-dimensional test models of tunnel excavation in geotechnical engineering, in particular to a three-dimensional model tunnel test device for simulating tunnel excavation settlement of a stratum containing cavities.

Background

With the development of economic society and the promotion of urbanization in China, the national demand for underground traffic construction is increasing. Subway, light rail and other rail transportation facilities are built in various places. The construction requirements of urban subway tunnels and a large number of highway and railway tunnels provide a lot of tests for geotechnical engineering tunnel construction technology. At present, the main modes of tunnel construction include a shield method, a mine method, a pipe jacking method and the like, and the scientific research and engineering evaluation methods before and after tunnel excavation mainly include a model test method, a numerical simulation method and the like. The model test method can vividly and intuitively simulate the whole process of tunnel stress, deformation and damage, can comprehensively and truly simulate a complex geological structure according to needs, reveals the influence of various factors on the tunnel excavation process, and provides a basis for establishing a new theoretical and mathematical model.

The existing tunnel three-dimensional model test device has a series of defects in how to air-dry soil, how to realize settlement displacement measurement, how to simulate the tunnel excavation process and how to adjust the position of a simulated tunnel.

In the aspect of air-drying soil bodies, the existing tunnel three-dimensional model test device adopts a natural air-drying mode, after soil with higher water content is added, the tunnel three-dimensional model test device stands for 1 to 2 weeks, and model tests are carried out after the soil bodies are completely air-dried and solidified to meet test requirements.

In the aspect of observation point displacement measurement, the existing tunnel three-dimensional model device mostly adopts equipment such as a total station instrument, a laser range finder and the like to measure. The total station mostly adopts a reflector and a prism as observation points, the distribution requirement is high, the measurement steps are complicated, the price of the instrument is high, and the disadvantage is obvious in a small model test system; the laser range finder belongs to sensitive optical instrument equipment, has higher requirements on the ambient light environment, has poorer signals in the environments of strong light and backlight, is difficult to ensure the measurement precision when the measured object has weaker reflectivity, such as black, and has weaker adaptability to the comprehensive environment.

In the aspects of simulating tunnel excavation and adjusting the position of a tunnel model, the conventional tunnel three-dimensional model test device mostly adopts a manual excavation mode. After the soil body is solidified, the tunnel is excavated manually according to parameters such as the buried depth and the diameter of the preset tunnel. The process often causes great disturbance to the soil body, and even the soil body in the model box can be collapsed, so that the test fails.

Disclosure of Invention

The invention aims to design a three-dimensional model tunnel test device for simulating excavation and settlement of a tunnel with a cavity stratum aiming at the existing tunnel three-dimensional model test device, overcomes the limitations of the existing tunnel model test device, realizes quick air drying, conveniently and accurately measures displacement, reduces disturbance of excavation on surrounding soil and is convenient for adjusting tunnel burial depth.

The invention has the technical scheme that the three-dimensional model tunnel test device for simulating the excavation settlement of the tunnel with the cavity stratum comprises: the box body is used for placing soil; the large air bag is arranged in the box body through a telescopic device and is used for simulating the change of the tunnel burial depth; the air drying device is arranged on the box body and used for accelerating the air drying of the soil body in the box body; the small air bags are arranged inside the box body and are used for forming stratum cavities; and the settlement displacement measuring device is arranged on the box body and is used for measuring the height of the soil body in the box body.

Further, a water permeable groove is formed in the side face of the box body; the air drying device is a high-speed electric fan and is right opposite to the water permeable groove of the box body.

Furthermore, the front end face of the box body is provided with at least two sliding blocks, and at least one sliding block is provided with a through hole corresponding to the big air sac.

Furthermore, the rear end face of the box body is provided with a small door capable of being opened and closed for controlling the small air bag.

Furthermore, the bottom of box is equipped with the hole of permeating water for accelerate the soil body in the box air-dries the consolidation.

Furthermore, the bottom end of the box body is provided with support legs for separating the bottom surface of the box body from the ground.

Furthermore, the telescopic device is a telescopic rod.

Furthermore, the settlement displacement measuring device comprises a marker, a spiral micrometer and at least two measuring rods, wherein the marker is arranged on a soil body in the box body, a measuring anvil and a micrometer screw of the spiral micrometer are respectively connected with the at least one measuring rod, and the measuring rods are used for measuring the height of the marker in the box body.

Further, the marker is an iron nail.

Further, the markers are provided in a plurality of rows.

The invention has the beneficial effects that: the air drying device, a large number of water permeable holes, water permeable grooves and the like are additionally arranged, so that the air drying and solidification of soil in the box body can be accelerated, and a large amount of test time can be saved; the settlement displacement measuring device in the box body uses the modified high-precision micrometer screw, so that the measurement is more convenient and simpler, the interference of the external environment can be resisted, and the precision is higher; the adjustment and the comparison test of the tunnel buried depth position are realized through the telescopic device, the large air bag and the through hole on the sliding block; the large air bag and the small air bag are respectively used for simulating a tunnel and a stratum cavity, and disturbance to the surrounding soil body is reduced as much as possible by means of slow deflation and taking out, so that the engineering environment in real tunnel construction is simulated to the greatest extent.

Drawings

FIG. 1 is a schematic structural diagram of a tunnel test device according to the present application;

FIG. 2 is a schematic structural diagram of the case of the present application, which does not include a slider;

fig. 3 is a schematic structural diagram of the settlement displacement measuring device of the present application.

In the above figures, 1, a box body; 11. a water permeable tank; 12. water permeable holes; 13. a support leg; 14. a slider;

2. a large air bag; 21. a telescoping device;

3. an air drying device;

4. a settlement displacement measuring device; 41. a micrometer screw; 42. and (6) measuring the rod.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the embodiments, structures, features and effects according to the present invention with reference to the accompanying drawings and preferred embodiments is as follows:

a three-dimensional model tunnel test device for simulating excavation and settlement of a tunnel with a cavity stratum comprises abox body 1, alarge air bag 2, anair drying device 3, a plurality of small air bags and a settlementdisplacement measuring device 4, wherein thelarge air bag 2, theair drying device 3, the small air bags and the settlementdisplacement measuring device 4 are arranged on the box body.

Referring to fig. 1, a soil body of a tunnel at the bottom of a tunnel is placed in abox body 1. The back, the double sides and the bottom of thebox body 1 are made of stainless steel materials, and the front is made of toughened glass, so that the observation is convenient. A dimension measuring ruler is arranged on the left side of the front surface of thebox body 1 and used for measuring the embedding depth.

Thebig air bag 2 is arranged in thebox body 1 through theexpansion device 21, the shape of thebig air bag 2 is designed into the shape (part) of the tunnel, and theexpansion device 21 is utilized to control the depth of thebig air bag 2 in thebox body 1, thereby realizing the change of the tunnel burial depth. Thebig air bag 2 is provided with an inflation inlet and an exhaust outlet, and can be inflated and deflated freely. Thetelescopic device 21 may be a telescopic rod. Preferably, with reference to fig. 2, the side of thebox body 1 is provided with a waterpermeable groove 11; the air-drying device 3 is a high-speed electric fan, the air-drying device 3 is over against the waterpermeable groove 11 of thebox body 1, and the air-drying device 3 blows in wind from the waterpermeable groove 11, so that the accelerated air-drying and solidification of soil in thebox body 1 are improved. Referring to fig. 1, four slidingblocks 14 can be slidably arranged on the front end face of thebox body 1, one slidingblock 14 is provided with a through hole corresponding to thebig air bag 2, the through hole is used for simulating a tunnel portal, and the foursliding blocks 14 can be placed in different orders to realize different burial depths of the tunnel portal. Here, the number of thesliders 4 may be plural, and the number of thesliders 14 provided with the through holes is not particularly limited, and needs to be dealt with as the case may be.

Referring to fig. 1, theair drying device 3 may be a high-speed electric fan with a diameter slightly smaller than that of thebox 1, and four bolts are fixed on thebox 1 and directly face the water permeable grooves on the side surface of thebox 1, and the air flow principle is applied to accelerate the air drying of the soil in thebox 1. On this basis, can also set up thehole 12 of permeating water in the bottom ofbox 1 for accelerate the soil body in thebox 1 air-dry the solidification, on this basis, the bottom ofbox 1 is equipped withstabilizer blade 13, with the bottom surface and the ground separation ofbox 1, further with higher speed the process of permeating water.

A plurality of small air bags are arranged inside the box body 1 (not shown), the small air bags are filled with air in advance and buried in the soil in thebox body 1, and after the soil is completely air-dried and solidified, the small air bags are slowly deflated and taken out to form a stratum cavity. For convenience of use, a small door capable of being opened and closed can be arranged on the back surface of thebox body 1 and used for conveniently controlling the small air bag to manufacture a stratum cavity.

Referring to fig. 1 and 3, the settlementdisplacement measuring device 4 is provided on thehousing 1, and preferably, a chute for allowing the settlement displacement measuringdevice 4 to slide is provided on thehousing 1. The height of the soil body in thebox body 1 before air drying is measured firstly, and then the height after air drying is measured, so that the measurement of the settlement displacement is realized. Preferably, the sedimentationdisplacement measuring device 4 can be a modified high-precision micrometer screw with a division value of 0.01mm, and comprises a marker, amicrometer screw 41 and two measuringrods 42. The markers are arranged on the soil body in thebox body 1, the measuring anvil and the micrometer screw of thespiral micrometer 41 are respectively connected with at least one measuringrod 42, the measuringrod 42 extends and covers thewhole box body 1, and the measuringrod 42 is used for measuring the heights of the markers in thebox body 1. The markers may be arranged in 2 to 3 rows in thehousing 1 using common iron nails having a diameter of 5.5mm and a length of 70mm, and the sedimentation thereof after a designated time interval is measured using the sedimentationdisplacement measuring device 4.

When the device is used, after a specified soil sample is prepared, the length of thetelescopic device 21 and the sequence of the slide blocks 14 are adjusted, thelarge air bag 2 of the simulated tunnel is enabled to be opposite to the through hole of theslide block 14, and the tunnel burial depth is recorded by the dimension measuring ruler on the left side of thebox body 1. Thebig air bag 2 is filled with air, and a layer of sponge is respectively paved at the positions of the waterpermeable grooves 11 and the waterpermeable holes 12 at the bottom and the side of thebox body 1 so as to prevent soil particles from flowing out. The method comprises the steps of filling soil into abox body 1, meanwhile, arranging a pore water pressure sensor and a soil pressure sensor at preset positions for monitoring the soil pressure and the pore water pressure inside thebox body 1, and meanwhile, arranging small air bags filled with air and used for simulating formation cavities at the preset positions. After the box body is filled with soil, thefan device 3 which can be quickly air-dried is opened, and the air-drying and consolidation of the soil in thebox body 1 are accelerated. After a period of time, after the air drying is finished, the back small door of thebox body 1 is opened, the small air bag which is embedded in advance and used for simulating the stratum cavity is deflated at a very slow speed, and the small air bag is taken out after the deflation is finished. After a period of time, 2 to 3 rows of iron nails for monitoring sedimentation are arranged on the soil layer at the top of thebox body 1, the measuringrod 42 is pushed into thebox body 1, and the original height of each iron nail is recorded. And then slowly deflating thelarge air bag 2 of the simulated tunnel, recording the change of the soil pressure and the water pressure in the process, re-measuring the height of each iron nail after deflation, measuring the height change of the iron nail every other day, and analyzing the result by combining the water and soil pressure in thebox body 1.

The invention has been described above with reference to a preferred embodiment, but the scope of protection of the invention is not limited thereto, and various modifications can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention, and features mentioned in the various embodiments can be combined in any way as long as there is no structural conflict, and any reference sign in the claims should not be construed as limiting the claim concerned, from which the embodiment is to be regarded as being exemplary and non-limiting in any way. Therefore, all technical solutions that fall within the scope of the claims are within the scope of the present invention.

Claims (7)

Translated fromChinese

1.一种模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，包括：1. a three-dimensional model tunnel test device for simulating the excavation and settlement of a cavity-containing stratum tunnel, is characterized in that, comprising:箱体(1)，用于放置土体；A box (1) for placing soil;大气囊(2)，通过伸缩装置(21)设置于所述箱体(1)内，用于模拟隧道埋深的变化；A large airbag (2) is arranged in the box body (1) through a telescopic device (21), and is used to simulate the change of the buried depth of the tunnel;风干装置(3)，设置于所述箱体(1)上，用于加速所述箱体(1)内土体风干；an air-drying device (3), arranged on the box body (1), for accelerating the air-drying of the soil in the box body (1);数个小气囊，设置于所述箱体(1)的内部，用于形成地层空洞；Several small airbags are arranged inside the box body (1) to form formation voids;以及沉降位移测量装置(4)，设置于所述箱体(1)上，用于测量箱体(1)内土体的高度，所述沉降位移测量装置(4)包括标识物、螺旋测微器(41)和至少两根测量杆(42)，所述标识物设置于所述箱体(1)内的土体上，所述螺旋测微器(41)的测砧和测微螺杆分别连接至少一根测量杆(42)，所述测量杆(42)用于所述箱体(1)内测量标识物的高度；and a settlement displacement measuring device (4) arranged on the box body (1) for measuring the height of the soil body in the box body (1), the settlement displacement measuring device (4) comprising a marker, a spiral micrometer a device (41) and at least two measuring rods (42), the markers are arranged on the soil body in the box body (1), and the anvil and the micrometer screw of the helical micrometer (41) are respectively at least one measuring rod (42) is connected, and the measuring rod (42) is used for measuring the height of the marker in the box body (1);其中，所述箱体(1)的前端面设有至少两个滑块(14)，至少一个所述滑块(14)设有与所述大气囊(2)对应的通孔。Wherein, at least two sliding blocks (14) are provided on the front end surface of the box body (1), and at least one of the sliding blocks (14) is provided with a through hole corresponding to the large airbag (2).2.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述箱体(1)的侧面设有透水槽(11)；所述风干装置(3)为高速电风扇，所述风干装置(3)正对所述箱体(1)的透水槽(11)。2. The three-dimensional model tunnel test device for simulating the excavation and settlement of a stratum tunnel containing a cavity according to claim 1, wherein the side of the box body (1) is provided with a water permeable groove (11); the air drying device ( 3) It is a high-speed electric fan, and the air drying device (3) is facing the water permeable groove (11) of the box body (1).3.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述箱体(1)的后端面设有可开关的小门，用于控制小气囊(4)。3. The three-dimensional model tunnel test device for simulating the excavation and settlement of tunnels containing cavities according to claim 1, is characterized in that, the rear end face of the box (1) is provided with a switchable door for controlling small Airbag (4).4.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述箱体(1)的底端设有透水孔(12)，用于加快所述箱体(1)内的土体风干固结。4. The three-dimensional model tunnel test device for simulating the excavation and settlement of a stratum tunnel containing voids according to claim 1, wherein the bottom end of the box body (1) is provided with a permeable hole (12) for accelerating the The soil in the box (1) is air-dried and consolidated.5.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述箱体(1)的底端设有支脚(13)，用于将所述箱体(1)的底面与地面分离。5. The three-dimensional model tunnel test device for simulating the excavation and settlement of a stratum tunnel containing voids according to claim 1, wherein the bottom end of the box body (1) is provided with a leg (13) for connecting the The bottom surface of the box body (1) is separated from the ground.6.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述伸缩装置(21)为伸缩杆。6 . The three-dimensional model tunnel test device for simulating the excavation and settlement of a stratum tunnel with voids according to claim 1 , wherein the telescopic device ( 21 ) is a telescopic rod. 7 .7.根据权利要求1所述的模拟含空洞地层隧道开挖沉降的三维模型隧道试验装置，其特征在于，所述标识物为铁钉。7 . The three-dimensional model tunnel test device for simulating the excavation and settlement of a stratum tunnel with voids according to claim 1 , wherein the markers are iron nails. 8 .

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