Large model box for measuring shear strength of coarse-grained soil and use method

Abstract

The invention discloses a large model box for measuring the shear strength of coarse-grained soil and a use method. The box comprises a model base and a model top cover. Two rectangular overlapping rings are arranged between the model base and the model top cover and connected with each other through a rubber film and a rectangular pressing strip. A cavity formed by the rectangular overlapping rings is filled with coarse-grained soil. Water permeable plates are arranged between the rectangular overlapping rings and the model base and between the rectangular overlapping rings and the model top cover respectively. A water inlet valve is arranged on the model base. A drainage valve is arranged on the rectangular overlapping ring on the top layer. A pressure valve for pressurizing coarse-grained soil is arranged on the model top cover. The model base is connected with a beam through a stand column. Each rectangular overlapping ring is connected with a dynamic displacement sensor. The inner wall of each rectangular overlapping ring is provided with a dynamic pressure sensor. Normal stress is exerted on the model box in an internal force loading mode, the model box is simple in overall structure, light in weight, convenient to move and wide in application range, and dynamic tests and static tests can be conducted on a small vibration table.

Description

technical field [0001] The invention relates to a large-scale model box for measuring the shear strength of coarse-grained soil and a use method thereof, belonging to the technical field of water conservancy engineering. Background technique [0002] In recent years, a number of high earth-rockfill dams have been built in western my country. Rockfill materials are the main materials for dam construction. The measurement of their static and dynamic characteristics is the premise of static and dynamic stability analysis of dams. At present, the measuring instruments for the shear strength of coarse-grained soil mainly include: large-scale direct shear instrument, large-scale static and dynamic three-axis instrument. [0003] Before the present invention, a Chinese patent (patent number: ZL200310110739.X) disclosed a coarse-grained soil direct shear instrument, which specified the shear plane position of the soil in the process of measuring the strength of the soil, which was i...

AI Technical Summary

Problems solved by technology

[0003] Before the present invention, a Chinese patent (patent number: ZL200310110739.X) disclosed a coarse-grained soil direct shear instrument, which specified the shear plane position of the soil in the process of measuring the strength of the soil, which was inconsistent with the actual working conditions. In addition, the change of pore pressure during the shearing process cannot be obtained during the test process. The application of normal stress during the test process requires a large load, and the instrument is relatively cumbersome, which can only be used to measure the static strength index of the soil.

Chinese patent (application number: 201510361856.6) discloses a strain-controlled gravel soil large-scale layer shear test device, which fails to consider the influence of water on the mechanical properties of the material during the test, and the normal stress is applied through the servo motor , the application of normal force is an external force application, and the base of the test instrument device is subjected to a large force

Chinese patent (patent number: ZL201210006950.6) discloses a two-way vibration instrument for measuring the interface between soil and structure. Influence of Soil Mechanical Properties

In actual engineering, many problems are closely related to water. Ignoring the influence of water in the test process will inevitably overestimate the shear strength of the soil, making the design and calculation results dangerous.

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