Small high-frequency low-stress amplitude soil dynamic triaxial apparatus

Abstract

The invention discloses a small high-frequency low-stress amplitude soil dynamic triaxial apparatus. The apparatus comprises a loading system, an acceleration measuring system, an axial force measuring system, a water pressure measuring system, an air pressure measuring system and a displacement measuring system. The loading system comprises a small electromagnetic vibration table, a piston, a cylinder, a weight, a pushing rod and a pressure chamber and can control static load and dynamic load. The static load is controlled by controlling axial stress and confining pressure. The axial stress is controlled by controlling thrust of the piston and weight of the weight, and the confining pressure is provided by the pressure chamber to achieve a high static stress level. The dynamic load is controlled by the small electromagnetic vibration table which applies inertial force to a sample in form of dynamic load through high-frequency vibration, to realize high vibration loading of high-frequency dynamic load and high measuring precision.

Description

Technical field [0001] The invention relates to the field of geotechnical engineering technology and environmental vibration engineering, in particular to a small-scale high-frequency low-stress amplitude soil dynamic triaxial instrument. Background technique [0002] The traffic load and mechanical vibration in the utilization of underground space have a dynamic load effect on the surrounding soil, which is characterized by a large number of cycles, a small dynamic stress amplitude, and the soil has a large normal stress level. Under such dynamic load, the soil can generate pore water pressure rise and soil softening. [0003] Hydraulic, pneumatic or gear-driven soil dynamic triaxial apparatus is a common experimental device for indoor experiments. It can reproduce the normal stress level (up to 400kPa), but its frequency is low (generally lower than 20Hz), and it is difficult to control the low stress amplitude (generally high The operating cost of long-term loading is high (the...

AI Technical Summary

Problems solved by technology

However, it is difficult to achieve a high normal stress level, and the confining pressure cannot be controlled, so it is difficult to simulate the three-dimensional force of the deep soil layer

[0005] At present, the indoor experimental device cannot meet these requirements at the same time, so it is necessary to design a high frequency (such as 100Hz), low dynamic stress amplitude (generally less than 5kPa), relatively high normal stress level (400kPa), and long-term loading. low cost device

The small-scale high-frequency low-stress amplitude soil dynamic triaxial instrument is an experimental device proposed to make up for the shortcomings of the above-mentioned instruments. Its design principle is completely different from that of previous instruments. At present, there is no such experimental device in China.

Images