Tangential loading method based on Lorentz force for shear test of super-large rock mass structural plane

Abstract

A tangential loading method based on the Lorentz force for the shear test of the super-large-scale rock mass structural plane. According to the data of the shear instability of the large-scale rock mass structural plane, after statistical analysis, the shear test of the super-large-scale rock mass structural plane is determined. For the physical and mechanical parameters of the wall rock and structural surface, use a cuboid steel mold to pour the super-sized rock mass structural surface concrete lower sample, and pour the upper sample according to the same method; arrange high-frequency current coils around the upper and lower samples, and change the coil The magnitude and direction of the current in the medium are used to adjust the magnitude and direction of the Lorentz force; the determined data of the current in the high-frequency coil is input into the intelligent computer, and the magnitude and direction of the current in the high-frequency coil are controlled by the current sub-controller; the experiment During the process, the fiber optic current sensor is deformed by pressure under the tangential load, and the data is transmitted to the intelligent computer through the fiber optic channel to correct the tangential load of the shear test. The invention improves the accuracy and scientificity of test results.

Description

technical field [0001] The invention relates to a tangential loading method for a super-large-scale rock mass structural surface shear test based on Lorentz force, and belongs to the technical field of indoor physical and mechanical tests. Background technique [0002] With the rapid development of the economy, my country's investment in large-scale infrastructure in the central and western regions is increasing, such as large-scale hydropower projects, high-speed railways, deep resource mining, strategic oil reserves, and nuclear power projects. The construction of these projects is in While improving people's living standards and promoting further economic development, it has also brought about more engineering geological disasters, such as landslides, debris flows, rockbursts, earthquakes, etc., resulting in prominent rock mass stability and catastrophe problems in the engineering area. Threats to people's lives and property safety. After investigation and research, most o...

AI Technical Summary

Problems solved by technology

However, for large open-air slopes, the size of the key structural surface of the overall slope and the composite step slope reaches tens of meters or even hundreds of meters. Due to the existence of the size effect of the structural surface shear strength, the traditional small indoor shear test The error of the obtained structural plane shear strength index is relatively large, so it is very necessary to conduct shear tests on super-sized rock mass structural planes

But there are the following problems: (1) The tangential load required for the super-large-scale rock mass structural surface shear test is very large, and the oil pressure loaded by the oil cylinder is very large, which has potential safety hazards; (2) The shear test at the end of the sample Loading in the same direction will cause local stress concentration, resulting in uneven distribution of tangential load, and the end of the sample will be damaged before the structural surface; (3) Arranging corbels on both sides, using multi-cylinder push method can realize tangential loading, but the The steel plate in the leg needs to penetrate the sample, which greatly damages the integrity of the sample, seriously affects the stress distribution in the rock mass, and there are large errors in the obtained data; (4) Considering safety issues, the test operator should stay away from the test The distance between the equipment is sufficient, and a long wire is required to transmit the control signal. Using a cable to transmit the signal will cause damage to the signal, and the waterproof, shock resistance, and anti-interference capabilities are not strong

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