Coarse-grained soil dynamic and static triaxial apparatus

Abstract

The present invention relates to a dynamic and static triaxial instrument for coarse-grained soil, comprising a base, a pressure chamber, a coarse-grained soil sample wrapped with a latex film, a frame structure and a servo oil cylinder, and a confining pressure loading system, wherein the pressure chamber is arranged directly above the servo oil cylinder; a chassis is fixed in the middle of the pressure chamber, a porous plate is fixed on the chassis, the coarse-grained soil sample is placed on the porous plate, a gap space is formed between the latex film of the coarse-grained soil sample and the inner wall of the pressure chamber, a porous plate, an upper pressure head, and a piston loading rod are arranged upward on the top of the coarse-grained soil sample in sequence, a pressure seat is fixed on the top of the pressure chamber, the piston loading rod can be vertically lifted and placed in a lifting hole, and the bottom end is matched and placed on the upper pressure head, and the top end is located below the top plate of the frame structure; the confining pressure loading system comprises a hydraulic control cabinet with adjustable water pressure, an upper high-pressure water supply assembly, a lower high-pressure water supply assembly, and a side high-pressure water supply hose. The present invention can provide different surrounding pressures, and then apply axial pressure to perform shearing experiments, thereby obtaining shear strength parameters.

Description

Technical Field

[0001] The invention relates to the technical field of coarse-grained soil experiments, in particular to a coarse-grained soil dynamic-static triaxial instrument. Background Art

[0002] The shear strength of coarse-grained soil is an important parameter in studying the soil properties of coarse-grained soil. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a coarse-grained soil dynamic and static triaxial apparatus, which can provide different ambient pressures, then apply axial pressure to perform shear tests, and then obtain shear strength parameters.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a coarse-grained soil dynamic and static triaxial instrument, comprising a base, a pressure chamber, and a coarse-grained soil sample wrapped with a latex film, the coarse-grained soil sample is placed in a containing inner cavity of the pressure chamber, and also comprising a frame structure and a servo oil cylinder fixed on the base, the pressure chamber is arranged directly above the servo oil cylinder; a chassis is fixed in the middle of the bottom end of the containing inner cavity of the pressure chamber, a porous plate is fixed on the chassis, the coarse-grained soil sample is placed on the porous plate, a gap space is formed between the latex film of the coarse-grained soil sample and the inner wall of the pressure chamber, a porous plate, an upper pressure head, and a piston loading rod are arranged upward from the top of the coarse-grained soil sample in sequence, a pressure seat is fixed on the top of the pressure chamber, and a lifting hole corresponding to the piston loading rod is opened on the pressure seat and the top of the pressure chamber, the piston loading rod can be placed in the lifting hole in a vertically lifting manner, and the bottom end is matched and placed on the upper pressure head, and the top end is located below the top plate of the frame structure;

[0005] It also includes a confining pressure loading system; a number of water-permeable holes in contact with the coarse-grained soil samples are evenly opened on the two porous plates, and water supply holes connected to the corresponding water-permeable holes on the porous plates are respectively opened on the upper pressure head and the chassis; the confining pressure loading system includes a water pressure control cabinet with adjustable water pressure, an upper high-pressure water supply assembly for supplying high-pressure water to the two water supply holes of the upper pressure head, a lower high-pressure water supply assembly for supplying high-pressure water to the two water supply holes of the chassis, and a side high-pressure water supply hose for supplying high-pressure water to the gap space, and the upper high-pressure water supply assembly, the lower high-pressure water supply assembly and the side high-pressure water supply hose are all connected to the water pressure control cabinet.

[0006] On the basis of the above technical solution, the upper high-pressure water supply assembly includes two upper high-pressure hoses, an upper water supply pipe, and a quick-insert high-pressure three-way valve. One end of the upper water supply pipe is connected to one end of the two upper high-pressure hoses through the quick-insert high-pressure three-way valve, and the other ends of the two upper high-pressure hoses are respectively connected to the two water delivery holes of the upper pressure head; the bottom of the pressure chamber is provided with two connecting holes connected to the gap space, one end of the side high-pressure water supply hose is connected to a connecting hole of the pressure chamber, and the other end of the upper water supply pipe is sealed through the other connecting hole of the pressure chamber and then connected to a connecting pipe with the other end of the side high-pressure water supply hose through a quick-insert high-pressure three-way valve;

[0007] The lower high-pressure water supply assembly includes two lower high-pressure hoses, a lower water supply pipe, and a quick-insert high-pressure three-way valve. One end of the lower water supply pipe is connected to one end of the two lower high-pressure hoses through the quick-insert high-pressure three-way valve, and the other ends of the two lower high-pressure hoses are respectively connected to the two water delivery holes of the chassis; the other end of the lower water supply pipe and the connecting pipe are both connected to the water pressure control cabinet.

[0008] On the basis of the above technical scheme, it also includes two guide frames distributed on both sides of the servo cylinder, and the two longitudinal ends of the two guide frames are fixedly connected to the base through support columns; four moving wheels are evenly fixed on the bottom surface of the pressure chamber and the pressure chamber is placed on the guide frame in a longitudinally movable manner through the cooperation of the moving wheels and the corresponding guide frames on both sides.

[0009] On the basis of the above technical solution, the pressure chamber includes a positioning disk and a protective tube sealedly fixed on the positioning disk, and the protective tube and the positioning disk enclose an accommodating inner cavity of the pressure chamber.

[0010] On the basis of the above technical solution, a card seat with a card cavity is fixed in the middle of the bottom surface of the pressure chamber, and a loading plate corresponding to the card cavity is fixed to the telescopic end of the piston of the servo oil cylinder.

[0011] Based on the above technical solution, the frame structure includes four columns vertically fixed on the base, and a top plate horizontally fixed between the top ends of the four columns.

[0012] Compared with the prior art, the invention has the following beneficial effects: the coarse-grained soil dynamic and static triaxial apparatus provided by the invention is an experimental instrument for measuring the shear strength of coarse-grained soil. It can use the confining pressure loading system to provide different surrounding pressures for the coarse-grained soil sample, and then use the servo oil cylinder and the piston loading rod to apply axial pressure to perform a shear test under a certain constant surrounding pressure, and then obtain the shear strength parameter according to the Mohr-Coulomb strength theory. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the present invention;

[0014] The numbers in the figure are: 1-base; 2-pressure chamber, 21-gap space, 22-pressure seat, 23-lifting hole, 24-connecting hole, 25-moving wheel, 26-positioning plate, 27-casing, 28-seat; 3-coarse-grained soil sample, 31-latex membrane, 32-chassis, 33-upper pressure head, 34-porous plate, 35-piston loading rod, 36-water delivery hole; 4-frame structure, 41-column, 42-top plate; 5-servo cylinder, 51-loading plate; 6-hydraulic control cabinet, 61-side high-pressure water supply hose, 62-quick-insert high-pressure three-way valve, 63-upper high-pressure hose, 64-upper water supply pipe, 65-connecting pipe, 66-lower high-pressure hose, 67-lower water supply pipe; 7-guide frame. DETAILED DESCRIPTION

[0015] 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 intended to limit the present invention.

[0016] Reference Figure 1 It can be seen that the coarse-grained soil dynamic and static triaxial apparatus includes a base 1, a pressure chamber 2, a coarse-grained soil sample 3 wrapped with a latex film 31, a frame structure 4 and a servo cylinder 5 fixed on the base 1, two guide rail frames 7 distributed on both sides of the servo cylinder 5, and a confining pressure loading system.

[0017] The frame structure 4 includes four columns 41 fixed vertically on the base 1, and a top plate 42 fixed horizontally between the tops of the four columns 41, and the servo cylinder 5 is located between the columns 41 on both sides. The two ends of the two guide rail frames 7 are fixedly connected to the base 1 through support columns; four moving wheels 25 are evenly fixed on the bottom surface of the pressure chamber 2, and the pressure chamber 2 can be placed on the guide rail frame 9 in a longitudinally movable manner through the cooperation of the moving wheels 25 and the corresponding guide rail frames 9 on both sides. The pressure chamber 2 is arranged directly above the servo cylinder 5, and a card seat 28 with a card cavity is fixed in the middle of the bottom surface of the pressure chamber 2. The piston telescopic end of the servo cylinder 5 is fixed with a loading plate 51 corresponding to the card cavity. The servo cylinder 5 is started to drive the loading plate 51 to be stuck in the card seat 28, and then drive the pressure chamber 2 to move upward.

[0018] The coarse-grained soil sample 3 is placed in the accommodating inner cavity of the pressure chamber 2. The pressure chamber 2 includes a positioning plate 26 and a casing 27 sealedly fixed on the positioning plate 26. The casing 27 and the positioning plate 26 enclose the accommodating inner cavity of the pressure chamber 2. A bottom plate 32 is fixed in the middle of the bottom end of the accommodating inner cavity of the pressure chamber 2. A porous plate 34 is fixed on the bottom plate 32. The coarse-grained soil sample 3 is placed on the porous plate 34. A gap space 21 is formed between the latex film 31 of the coarse-grained soil sample 3 and the inner wall of the pressure chamber 2. The top of the coarse-grained soil sample 3 is sequentially upwardly provided with a porous plate 34, an upper pressure head 33, and a piston loading rod 35. A pressure seat 22 is fixed on the top of the pressure chamber 2. The pressure seat 22 and the top of the pressure chamber 2 are both provided with a lifting hole 23 corresponding to the piston loading rod 35. The piston loading rod 35 can be vertically lifted and placed in the lifting hole 23 and the bottom end is matched and placed on the upper pressure head 33, and the top end is located below the top plate 42 of the frame structure 4. The servo cylinder 5 drives the pressure chamber 2 to move upward, and the piston loading rod 35 moves upward until the top end of the piston loading rod 35 contacts the top plate 42 of the frame structure 4. The piston loading rod 35 begins to move downward and inserts into the pressure chamber 2 and presses down the upper pressure head 33, and then the servo cylinder 5 and the piston loading rod 35 cooperate with each other to apply axial pressure to the coarse-grained soil sample 3.

[0019] A plurality of water-permeable holes in contact with the coarse-grained soil sample are evenly formed on the two porous plates 34 , and water delivery holes 36 communicating with the water-permeable holes on the corresponding porous plates 34 are respectively formed on the upper pressure head 33 and the bottom plate 32 .

[0020] The confining pressure loading system includes a water pressure control cabinet 6 with adjustable water pressure, an upper high-pressure water supply assembly for supplying high-pressure water to the two water holes of the upper pressure head 33, a lower high-pressure water supply assembly for supplying high-pressure water to the two water holes of the chassis 32, and a side high-pressure water supply hose 61 for supplying high-pressure water to the gap space 21. The upper high-pressure water supply assembly, the lower high-pressure water supply assembly and the side high-pressure water supply hose 61 are all connected to the water pressure control cabinet 6.

[0021] The upper high-pressure water supply assembly includes two upper high-pressure hoses 63, an upper water supply pipe 64, and a quick-insert high-pressure three-way valve 62. One end of the upper water supply pipe 64 is connected to one end of the two upper high-pressure hoses 63 through the quick-insert high-pressure three-way valve 62, and the other ends of the two upper high-pressure hoses 63 are respectively connected to the two water delivery holes 36 of the upper pressure head 33; two connecting holes 24 connected to the gap space 21 are opened at the bottom of the pressure chamber 2, one end of the side high-pressure water supply hose 61 is connected to a connecting hole 24 of the pressure chamber 2, and the other end of the upper water supply pipe 64 is sealed through the other connecting hole of the pressure chamber 2 and then connected to a connecting pipe 65 with the other end of the side high-pressure water supply hose 61 through a quick-insert high-pressure three-way valve 62.

[0022] The lower high-pressure water supply assembly includes two lower high-pressure hoses 66, a lower water supply pipe 67, and a quick-insert high-pressure three-way valve 62. One end of the lower water supply pipe 67 is connected to one end of the two lower high-pressure hoses 66 through the quick-insert high-pressure three-way valve 62, and the other ends of the two lower high-pressure hoses 66 are respectively connected to the two water delivery holes 36 of the chassis 32; the other end of the lower water supply pipe 67 and the connecting pipe 65 are both connected to the water pressure control cabinet 61. The water pressure control cabinet 61 is a prior art, and a booster pump and a control system are provided in the water pressure control cabinet. The control system controls the booster pump to adjust the water pressure to provide water pressures of different pressures for the upper high-pressure water supply assembly, the lower high-pressure water supply assembly, and the side high-pressure water supply hose. Its principle and specific structure are not repeated here.

[0023] The coarse-grained soil test instrument provided by the present invention can provide different surrounding pressures for the coarse-grained soil sample by using the confining pressure loading system, and then perform a shear test by using the servo oil cylinder and the piston loading rod to apply axial pressure under a certain constant surrounding pressure, and then obtain the shear strength parameters according to the Mohr-Coulomb strength theory.

Claims

1. A coarse-grained soil dynamic and static triaxial apparatus, comprising a base, a pressure chamber, and a coarse-grained soil sample wrapped with a latex film, wherein the coarse-grained soil sample is placed in the receiving inner cavity of the pressure chamber, and is characterized in that: It also includes a frame structure and a servo oil cylinder fixed on the base, and a pressure chamber is arranged directly above the servo oil cylinder; a chassis is fixed in the middle of the bottom end of the accommodating inner cavity of the pressure chamber, a porous plate is fixed on the chassis, a coarse-grained soil sample is placed on the porous plate, a gap space is formed between the latex membrane of the coarse-grained soil sample and the inner wall of the pressure chamber, a porous plate, an upper pressure head, and a piston loading rod are arranged upward from the top of the coarse-grained soil sample in sequence, a pressure seat is fixed on the top of the pressure chamber, and a lifting hole corresponding to the piston loading rod is opened on the pressure seat and the top of the pressure chamber, and the piston loading rod can be placed in the lifting hole in a vertically lifting manner, and the bottom end is matched and placed on the upper pressure head, and the top end is located below the top plate of the frame structure; It also includes a confining pressure loading system; a plurality of water-permeable holes in contact with the coarse-grained soil sample are evenly opened on the two porous plates, and water delivery holes connected to the corresponding water-permeable holes on the porous plates are respectively opened on the upper pressure head and the bottom plate; the confining pressure loading system includes a water pressure control cabinet with adjustable water pressure, an upper high-pressure water supply assembly for supplying high-pressure water to the two water delivery holes of the upper pressure head, a lower high-pressure water supply assembly for supplying high-pressure water to the two water delivery holes of the bottom plate, and a side high-pressure water supply hose for supplying high-pressure water to the gap space, and the upper high-pressure water supply assembly, the lower high-pressure water supply assembly and the side high-pressure water supply hose are all connected to the water pressure control cabinet; The pressure chamber comprises a positioning plate and a protective sleeve sealedly fixed on the positioning plate, and the protective sleeve and the positioning plate enclose an accommodating inner cavity of the pressure chamber.

2. The coarse-grained soil dynamic and static triaxial apparatus according to claim 1, characterized in that: The upper high-pressure water supply assembly includes two upper high-pressure hoses, an upper water supply pipe, and a quick-insert high-pressure three-way valve. One end of the upper water supply pipe is connected to one end of the two upper high-pressure hoses through the quick-insert high-pressure three-way valve, and the other ends of the two upper high-pressure hoses are respectively connected to the two water delivery holes of the upper pressure head; the bottom of the pressure chamber is provided with two connecting holes connected to the gap space, one end of the side high-pressure water supply hose is connected to a connecting hole of the pressure chamber, and the other end of the upper water supply pipe is sealed through the other connecting hole of the pressure chamber and then connected to a connecting pipe with the other end of the side high-pressure water supply hose through a quick-insert high-pressure three-way valve; The lower high-pressure water supply assembly includes two lower high-pressure hoses, a lower water supply pipe, and a quick-insert high-pressure three-way valve. One end of the lower water supply pipe is connected to one end of the two lower high-pressure hoses through the quick-insert high-pressure three-way valve, and the other ends of the two lower high-pressure hoses are respectively connected to the two water delivery holes of the chassis; the other end of the lower water supply pipe and the connecting pipe are both connected to the water pressure control cabinet.

3. The coarse-grained soil dynamic and static triaxial apparatus according to claim 1, characterized in that: It also includes two guide rail frames distributed on both sides of the servo cylinder, and the two longitudinal ends of the two guide rail frames are fixedly connected to the base through support columns; four moving wheels are evenly fixed on the bottom surface of the pressure chamber, and the pressure chamber can be longitudinally moved on the guide rail frames through the cooperation of the moving wheels and the corresponding guide rail frames on both sides.

4. The coarse-grained soil dynamic and static triaxial apparatus according to claim 1, characterized in that: A card seat with a card cavity is fixed in the middle of the bottom surface of the pressure chamber, and a loading plate corresponding to the card cavity is fixed at the telescopic end of the piston of the servo oil cylinder.

5. The coarse-grained soil dynamic and static triaxial apparatus according to claim 1, characterized in that: The frame structure comprises four columns vertically fixed on the base, and a top plate horizontally fixed between the top ends of the four columns.

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