Large-size frozen soil true triaxial loading test device

Abstract

The invention belongs to the technical field of geotechnical test equipment, and relates to a large-size frozen soil true triaxial loading test device which adopts a three-direction principal stress independent control loading mode and can well simulate a three-dimensional crustal stress state actually existing in a geological environment. The vertical principal stress is applied by a vertical loading device, the horizontal principal stress is applied by two horizontal loading devices, and the test piece is allowed to deform freely in three directions under the action of the three-dimensionalprincipal stress; the structure is simple, the operation is convenient, and the vertical loading system adopts a dynamic and static combined loading mode; a hydraulic cylinder loading mode is adoptedin four horizontal loading directions; static loading in the three-axis direction is all independently controlled, the hydraulic cylinder in each direction can move synchronously and asynchronously, each loading point can use displacement control loading or test force control loading, in the three-axis direction test, a long-time pressure stabilizing state can be achieved, and the pressure maintaining precision reaches + / -0.5%.

Description

Technical field: [0001] The invention belongs to the technical field of geotechnical test equipment, and relates to a large-scale true triaxial loading test device for frozen soil, in particular to a large-scale true three-dimensional loading system for studying the three-dimensional stress state of an open system of engineering geological environment in cold regions. Background technique: [0002] At present, there is no multifunctional test equipment at home and abroad that integrates the function of one-way freeze-thaw test, low-temperature static and dynamic triaxial test (ordinary triaxial test, true triaxial test), and the current freeze-thaw test equipment can only realize systematic is one-way open and is k 0 State test, the actual ground stress state of the horizontal free site is σ 1 >σ 2 = σ 3 , while the ground stress state of the slope or horizontal non-free site is σ 1 >σ 2 >σ 3 , the current low-temperature static and dynamic triaxial test condi...

AI Technical Summary

Problems solved by technology

[0002] At present, there is no multifunctional test equipment at home and abroad that integrates the function of one-way freeze-thaw test, low-temperature static and dynamic triaxial test (ordinary triaxial test, true triaxial test), and the current freeze-thaw test equipment can only realize systematic is one-way open and is k 0 State test, the actual ground stress state of the horizontal free site is σ 1 >σ 2 = σ 3 , while the ground stress state of the slope or horizontal non-free site is σ 1 >σ 2 >σ 3 , the current low-temperature static and dynamic triaxial test conditions can only simulate the former, so the test results can only be used to study the problem of horizontal free sites, not suitable for the study of slopes or non-free sites. The impact of the size effect on the test results makes it impossible to complete the three-dimensional open system freeze-thaw test under actual complex stress conditions, and it is even more impossible to realize the dynamic monitoring and real-time display of the internal structure, temperature, moisture, ice crystals, salt, etc. of the test piece during the test. It is used to study the above-mentioned multi-field coupling effect and mutual feedback effect

Images