Consolidation apparatus with lateral flexible wall

Abstract

The utility model provides a lateral flexible wall consolidometer, which comprises a rigid sleeve, a flexible film, an inner sleeve and a displacement monitoring device, and is characterized in that the inner sleeve comprises an upper annular cylinder, a lower annular cylinder and a screw rod; the rigid sleeve comprises a connector and a through hole. The flexible film is positioned in the middle of the rigid sleeve and sleeves the outer wall surfaces of the upper and lower annular cylinders; and the screw rod is fixed in the middle of the upper-lower annular cylinder. A displacement monitoring device is installed in the middle of the rigid sleeve, and a telescopic head of the displacement monitoring device makes contact with the flexible film and is used for measuring horizontal deformation of the flexible film. The device disclosed by the utility model can measure the lateral pressure of a soil sample while consolidating, can solve the problem of errors caused by rigidity difference in a traditional measurement method, improves the accuracy of a test result, and has an irreplaceable effect on analyzing the mechanical property of a soil material and predicting consolidation parameters. Through actual measurement and comparison, the device can improve the precision of the lateral force measurement result of the soil sample in the consolidation process by about 45%, and has very important practical significance and application value.

Description

Technical Field

[0001] The utility model belongs to the field of geotechnical engineering test research and relates to a lateral flexible wall consolidation instrument used for conventional consolidation tests and special consolidation tests of soil materials under various stress states. Background Art

[0002] For the study of stress-strain properties of rock and soil, it is very important to accurately obtain the deformation and consolidation parameters of the test material in the consolidation state. However, in the existing soil consolidation test, since the lateral contact wall of the soil is completely rigid and semi-rigid, it is difficult to ignore the stress concentration problem and the problem of poor stiffness using traditional stress measurement equipment. Therefore, there are certain errors in the measurement of the lateral force of the soil during the consolidation process, as shown in the literature "Study on Static Earth Pressure Coefficient". A lateral flexible wall consolidator is urgently needed to improve the measurement accuracy of the lateral stress of the soil in the consolidation test, which has important practical significance for the study of the constitutive relationship model and engineering research of geotechnical engineering. Utility Model Content

[0003] In view of the problems existing in the prior art, the utility model provides a consolidation instrument with a lateral flexible wall, which is used to improve the measurement accuracy of soil lateral stress in a consolidation test.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A lateral flexible wall consolidation instrument, the consolidation instrument comprises a rigid sleeve, a flexible membrane, an inner sleeve, a displacement monitoring device, and a loading cap, wherein the inner sleeve comprises an upper annular cylinder, a lower annular cylinder, and a screw rod; the rigid sleeve comprises an interface and a through hole. The details are as follows:

[0006] The rigid sleeve is a hollow cylindrical structure with upper and lower openings. The top of the rigid sleeve and the lower part of the side of the cylinder wall are both provided with interfaces that penetrate the cylinder wall. The top interface is used for exhaust and drainage, and the lower interface of the side of the cylinder wall is used for water injection. A plurality of equally spaced through holes are arranged in the middle of the cylinder wall for installing a displacement monitoring device, wherein the telescopic head of the displacement monitoring device contacts the flexible membrane and is used to measure the horizontal deformation of the flexible membrane. The loading cap is cylindrical, and the loading cap is arranged with a displacement monitoring device. A circle of raised structures as flange 1 is processed outwardly at the bottom of the rigid sleeve, and screw holes of equal spacing are distributed on flange 1 for fixing the rigid sleeve to the lower annular cylinder; a circle of raised structures as flange 2 is processed inwardly at the top of the rigid sleeve, and a top interface 11 is processed on flange 2. The lower surfaces of flange 1 and flange 2 are both provided with a circle of grooves for installing O-rings. The upper annular cylinder and the lower annular cylinder are connected by a screw. The flexible film is sleeved on the annular tube and the lower annular tube, and is clamped on the upper annular tube and the lower annular tube through the O-ring clamping groove.

[0007] The flexible membrane is located in the middle of the rigid sleeve and is sleeved on the outer wall surfaces of the small-diameter ends of the upper and lower annular cylinders that are symmetrically arranged; the non-through threaded holes in the middle of the upper and lower annular cylinders are used to fix the screw rod.

[0008] Furthermore, the upper annular cylinder is a two-stage cylindrical integrated structure, which is hollow inside and located above the rigid sleeve, and includes an upper large cylinder and a lower small cylinder, with a non-through threaded hole in the middle. A groove is also provided at the top of the upper cylinder corresponding to the groove, for installing an O-ring, and a threaded hole for installing a screw rod is provided on the bottom surface of the cylindrical structure. The bottom wall of the lower cylinder is processed with a chamfered structure, and a groove for installing an O-ring is also provided at the bottom of the cylinder.

[0009] Furthermore, the lower annular cylinder is a two-stage cylindrical integrated structure, located below the rigid sleeve, and the lower annular cylinder includes two cylindrical parts, an upper small part and a lower large part, with a threaded hole in the middle that is not through and symmetrically arranged with the threaded hole of the upper annular cylinder, a through drainage hole in the middle to connect a pressure gauge to test pore water pressure, and a water-permeable plate inlaid on the upper part. A groove is also provided at the bottom of the lower cylinder corresponding to the groove, for mounting an O-ring, and a threaded hole for mounting a screw rod is provided on the top surface of the cylindrical structure; the top wall of the upper cylinder is processed with a chamfered structure, and a groove for mounting an O-ring is also provided on the top of the cylinder.

[0010] The flexible membrane is located in the middle of the rigid sleeve and is sleeved on the outer wall surface of the small diameter end of the annular tube and the lower annular tube symmetrically arranged. The threaded holes in the middle of the upper annular tube and the lower annular tube are used to fix the screw rod.

[0011] A method for using a lateral flexible wall consolidation instrument comprises the following steps:

[0012] Step 1: Assemble the Lateral Flexible Wall Consolidation Apparatus

[0013] First, assemble the upper annular tube and the lower annular tube by connecting the threaded holes through a screw rod; the flexible membrane is sleeved on the annular tube and the lower annular tube, and is clamped on the groove with an O-ring, thereby tightening the flexible membrane on the upper annular tube and the lower annular tube; the end of the rigid sleeve with an outward flange is downwardly sleeved on the inner sleeve 3, and the upper and lower ends of the rigid sleeve and the inner sleeve are compressed and sealed by an O-ring, and the screw holes of the rigid sleeve and the inner sleeve are aligned, and tightened with screws to assemble; finally, the displacement monitoring device is installed in the through hole of the rigid sleeve.

[0014] The second step is to place the soil sample to be tested in the inner sleeve;

[0015] The third step is to pass water through the interface at the bottom of the rigid sleeve until water flows out of the interface at the top of the rigid sleeve, at which point the gap between the inner wall of the rigid sleeve and the flexible membrane is completely filled with water;

[0016] Step 4: The interface at the bottom of the rigid sleeve is connected to any type of liquid pressure controller. The displacement monitoring device will have data changes when it contacts the flexible membrane that wraps the tested sample. The pressure is adjusted by the liquid pressure controller so that the displacement monitoring device returns to the initial value, and the loading cap starts to load pressure at the same time.

[0017] The fifth step is to adjust the lateral pressure applied to the soil by the liquid pressure controller according to the lateral and axial deformations of the soil read by the displacement monitoring device according to different consolidation test types, so that the lateral deformation of the soil is within the control range.

[0018] The beneficial effects of the utility model are:

[0019] A lateral flexible wall consolidation instrument adopts a lateral liquid pressure constraint method to improve the measurement accuracy of soil lateral stress in a consolidation test, and solves the problems of poor stiffness and stress concentration in traditional pressure sensor tests. The utility model can simultaneously realize the k0 consolidation, confined consolidation and unconfined consolidation tests of rock and soil bodies, and has important practical significance for the study of constitutive relationship models and engineering research in geotechnical engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the lateral flexible wall consolidation apparatus of the utility model;

[0021] Figure 2 It is a top view schematic diagram of the lateral flexible wall consolidation instrument of the utility model;

[0022] Figure 3 This is a schematic diagram of the lower annular cylinder of the utility model;

[0023] Figure 4 It is a top view schematic diagram of the lower annular cylinder of the utility model;

[0024] In the figure: 1 rigid sleeve; 2 flexible membrane; 3 inner sleeve; 4 displacement monitoring device; 5 O-ring; 6 loading cap; 11 interface; 12 through hole; 13 outward flange 1; 14 inward flange 2; 31 upper annular cylinder; 32 lower annular cylinder; 33 screw rod; 131 screw hole; 311 groove; 312 threaded hole; 313 drainage hole; 314 water-permeable plate; 315 pressure gauge. DETAILED DESCRIPTION

[0025] A lateral flexible wall consolidation apparatus and a method of using the same according to the present invention will be described below in conjunction with the accompanying drawings.

[0026] A lateral flexible wall consolidation instrument, a rigid sleeve 1, a flexible membrane 2, an inner sleeve 3, a displacement monitoring device 4, and a loading cap 6, wherein the inner sleeve 3 includes an upper annular cylinder 31, a lower annular cylinder 32, and a screw rod 33; the rigid sleeve 1 includes an interface 11 and a through hole 12, as shown in the attached Figure 1 .

[0027] The rigid sleeve 1 is a hollow cylindrical structure with openings at the top and bottom. Figure 1 The top of the rigid sleeve 1 and the lower part of the side of the cylinder wall are both provided with interfaces 11 penetrating the cylinder wall. The top interface 11 is used for exhaust and drainage, and the lower interface 11 on the side of the cylinder wall is used for water injection. Four through holes 12 with equal spacing are arranged in the middle of the cylinder wall for installing four displacement monitoring devices 4, wherein the telescopic head of the displacement monitoring device 4 contacts the flexible membrane 2 and is used to measure the horizontal deformation of the flexible membrane 2. The loading cap 6 is cylindrical and is provided with the displacement monitoring device 4, as shown in the attached Figure 1 The bottom of the rigid sleeve 1 is processed outwardly with a circle of raised structures as flange 13, and the flange 13 is provided with screw holes 131 at equal intervals for fixing the rigid sleeve 1 to the lower annular tube 32; the top of the rigid sleeve 1 is processed inwardly with a circle of raised structures as flange 2 14, and the flange 2 14 is processed with a top interface 11, as shown in the attached Figure 1 The lower surfaces of the flange 13 and the flange 2 14 are each provided with a groove 311 for mounting the O-ring 5. Figure 1 .

[0028] The upper annular cylinder 31 is a two-stage cylindrical integrated structure, hollow inside, located above the rigid sleeve 1, and includes an upper large cylinder and a lower small cylinder, with a non-through threaded hole 312 in the middle. A groove is also provided at the top of the upper cylinder corresponding to the groove 311, for mounting the O-ring 5, and a threaded hole 312 for mounting the screw 33 is provided on the bottom surface of the cylindrical structure, as shown in the attached Figure 1 The bottom wall of the cylinder below is processed with a chamfered structure, and a groove 311 for installing the O-ring 5 is also provided below the cylinder. Figure 1 .

[0029] The lower annular cylinder 32 is a two-stage cylindrical integrated structure, located below the rigid sleeve 1. The lower annular cylinder 32 includes two cylindrical parts, the upper small part and the lower large part. The middle part is provided with a threaded hole 312 which is not through and is arranged symmetrically with the threaded hole 312 of the upper annular cylinder. The middle part is provided with a through drainage hole 313 connected to a pressure gauge 315 for testing pore water pressure. The upper part is inlaid with a permeable plate 314. Figure 3 The bottom of the lower cylinder is also provided with a groove corresponding to the groove 311, which is used to install the O-ring 5, and the top surface of the cylinder is provided with a threaded hole 312 for installing the screw 33; the top wall of the upper cylinder is processed with a chamfered structure, and the top of the cylinder is also provided with a groove 311 for installing the O-ring 5. The upper annular cylinder 31 and the lower annular cylinder 32 are connected by a screw 33, as shown in the attached figure. Figure 1 and attached Figure 3 .

[0030] The flexible membrane 2 is located in the middle of the rigid sleeve 1 and is sleeved on the outer wall of the small diameter end of the annular cylinder 31 and the lower annular cylinder 32, which are symmetrically arranged. The threaded hole 312 in the middle of the upper annular cylinder 31 and the lower annular cylinder 32 is used to fix the screw rod 33. Figure 1 and attached Figure 4 .

[0031] A method for using a lateral flexible wall consolidation instrument comprises the following steps:

[0032] Step 1: Assemble the Lateral Flexible Wall Consolidation Apparatus

[0033] First, the upper annular cylinder 31 and the lower annular cylinder 32 are connected to the threaded hole 312 by the screw rod 33 for assembly; the tested sample is wrapped with the flexible film 2, and then the flexible film 2 is sleeved on the annular cylinder 31 and the lower annular cylinder 32, and the O-ring 5 is clamped on the groove 311, thereby tightening the flexible film 2 on the upper annular cylinder 31 and the lower annular cylinder 32. At this time, the tested sample wrapped by the flexible film 2 is placed between the upper annular cylinder 31 and the lower annular cylinder 32, and the tested sample is placed between the upper annular cylinder 31 and the lower annular cylinder 32. A water-permeable plate 314 is placed between the lower annular cylinder 32; one end of the rigid sleeve 1 with the outward flange 13 is downwardly sleeved on the inner sleeve 3, and the upper and lower ends of the rigid sleeve 1 and the inner sleeve 3 are compressed and sealed by O-rings 5, and the screw holes 131 of the rigid sleeve 1 and the inner sleeve 3 are aligned and tightened with screws to assemble; the pressure gauge 315 is connected to the drainage hole 313 on the lower annular cylinder 32; finally, the displacement monitoring device 4 is installed in the through hole 12 of the rigid sleeve 1, as shown in the attached Figure 1 .

[0034] The second step is to place the soil sample to be tested in the inner sleeve 3, as shown in the attached Figure 1 ;

[0035] The third step is to pass water through the interface 11 at the lower part of the rigid sleeve 1 until water flows out of the interface 11 at the upper part of the rigid sleeve 1. At this time, the gap between the inner wall of the rigid sleeve 1 and the flexible membrane 2 is completely filled with water. Figure 1 ;

[0036] In the fourth step, the interface 11 at the bottom of the rigid sleeve 1 is connected to any type of liquid pressure controller. The displacement monitoring device 4 will have data changes when it contacts the flexible membrane 2 that wraps the tested sample, and the data of the axial contraction of the displacement monitoring device 4 is taken as a positive value. The pressure is adjusted by the liquid pressure controller to restore the displacement monitoring device 4 to the initial value. The displacement monitoring device 4 placed at the loading cap 6 is first pre-pressed to a data value, and the loading cap 6 starts to load pressure. Figure 1 The data output of the displacement monitoring device 4 placed at the loading cap 6 shows that the axial strain of the soil is:

[0037]

[0038] In the formula, ε A is the axial strain of the soil material, Δh is the data output value of the displacement monitoring device 4 placed at the loading cap 6, and H is the initial height of the soil material;

[0039] In the fifth step, according to different consolidation test types, the lateral deformation of the soil material is read by the four displacement monitoring devices 4, and the pressure applied to the lateral side of the soil material by the liquid pressure controller is adjusted so that the lateral deformation of the soil material is within the control range. The data conversion between the lateral deformation of the soil material and the readings of the four displacement monitoring devices is:

[0040]

[0041] In the formula, ε R is the lateral strain of the soil; l1, l2, l3, l4 are the output data of the four displacement monitoring devices, and the order is not distinguished; L is the initial circumference of the soil.

[0042] The above-described embodiments merely express the implementation methods of the present invention, but they cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A lateral flexible wall consolidation apparatus, characterized in that: The consolidation instrument comprises a rigid sleeve (1), a flexible membrane (2), an inner sleeve (3), a displacement monitoring device (4), and a loading cap (6), wherein the inner sleeve (3) comprises an upper annular cylinder (31), a lower annular cylinder (32), and a screw rod (33); the rigid sleeve (1) comprises an interface (11) and a through hole (12); the details are as follows: The rigid sleeve (1) is a hollow cylindrical structure with openings at the top and bottom. The top and lower side of the rigid sleeve (1) are both provided with interfaces (11) penetrating the wall. The top interface (11) is used for exhaust and drainage, and the lower side interface (11) is used for water injection. A plurality of through holes (12) are arranged at equal intervals in the middle of the wall for installing a displacement monitoring device (4). The telescopic head of the displacement monitoring device (4) contacts the flexible membrane (2) for measuring the horizontal deformation of the flexible membrane (2). The loading cap (6) is cylindrical and is provided with the displacement monitoring device (4). The bottom of the rigid sleeve (1) is processed outwardly with a circle of raised structures as flange one (13), and the flange one (13) is provided with screw holes (131) at equal intervals for fixing the rigid sleeve (1) to the lower annular cylinder (32); the top of the rigid sleeve (1) is processed inwardly with a circle of raised structures as flange two (14), and the flange two (14) is provided with a top interface (11); the lower surfaces of the flange one (13) and the flange two (14) are both provided with a circle of grooves (311) for installing an O-ring (5); the upper annular cylinder (31) and the lower annular cylinder (32) are connected by a screw rod (33); The flexible membrane (2) is located in the middle of the rigid sleeve (1) and is sleeved on the outer wall surfaces of the symmetrically arranged small-diameter ends of the upper annular cylinder (31) and the lower annular cylinder (32); the non-through threaded holes (312) in the middle of the upper annular cylinder (31) and the lower annular cylinder (32) are used to fix the screw rod (33).

2. A lateral flexible wall consolidation apparatus according to claim 1, characterized in that: The upper annular cylinder (31) is a two-stage cylindrical integrated structure, hollow inside, located above the rigid sleeve (1), and comprises an upper large cylinder and a lower small cylinder, with a non-through threaded hole (312) in the middle; A groove is also provided at a position corresponding to the groove (311) on the top of the upper cylinder to cooperate with the installation of the O-ring (5), and a threaded hole (312) for installing the screw rod (33) is provided on the bottom surface of the cylindrical structure; a chamfered structure is processed on the bottom wall of the lower cylinder, and a groove (311) for installing the O-ring (5) is also provided on the bottom of the cylinder.

3. A lateral flexible wall consolidation apparatus according to claim 1, characterized in that: The lower annular cylinder (32) is a two-stage cylindrical integrated structure, located below the rigid sleeve (1). The lower annular cylinder (32) includes two cylindrical parts, an upper small part and a lower large part. A threaded hole (312) is provided in the middle part, which is not through and is arranged symmetrically with the threaded hole (312) of the upper annular cylinder. A through drainage hole 313 is provided in the middle part to connect a pressure gauge (315) for testing pore water pressure. A water-permeable plate (314) is inlaid on the upper part. A groove is also provided at the corresponding position of the bottom of the lower cylinder and the groove (311) to cooperate with the installation of the O-ring (5), and a threaded hole (312) for installing the screw rod (33) is provided on the top surface of the cylindrical structure. The top wall of the upper cylinder is processed with a chamfered structure, and a groove (311) for installing the O-ring (5) is also provided on the top of the cylinder.

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