Method and system for testing the bond performance between rock and soil and anchors under simulated ground pressure

Abstract

The invention discloses a system and method for testing the bonding performance of the undisturbed rock-soil body and the anchorage body under the action of simulated formation pressure, which includes a measuring device, a sample fixing device, a formation pressure simulation device and a pressure grouting device. A pressure capsule is installed separately from the top surface, and a radial deformation measuring gauge is installed on the outside of the sample. One end of the grouting plug and the grouting plug are both topless conical shapes, and an exhaust valve is installed at the bottom of the support beam. The invention can perform pressure grouting on the sample and monitor its radial deformation. The double pressure bladder can apply pressure to the sample laterally and vertically to simulate the formation pressure. Silicone pads and steel sheets with holes are placed on the sample. The end friction effect is eliminated below, and the rock / adobe is compressed and restored to the initial formation pressure to limit its vertical deformation. The stress state, stress path and preparation process of the sample are consistent with the actual situation of the bolt, and are suitable for various working conditions. Bond performance test of rock-soil mass and anchor.

Description

technical field [0001] The invention relates to a bolt testing technology often used in engineering such as slopes, foundation pits, tunnels, mines, and traffic, and in particular to a testing system and testing method for the bonding performance of undisturbed rock-soil bodies and anchoring bodies under the action of simulated formation pressure. Background technique [0002] Bolt support technology is widely used in geotechnical engineering such as slopes, foundation pits, tunnels, mines, etc. due to its advantages of convenient construction and low cost. In engineering, the bearing capacity of the bolt is mostly evaluated according to the results of the field test. Although the field test can reflect the actual bearing characteristics of the bolt, it has high cost, long test cycle time, affects the construction period, and cannot simulate various working conditions (such as heavy rain Working conditions, dry and wet cycle conditions, etc.) and other shortcomings. [0003...

AI Technical Summary

Problems solved by technology

A cylindrical loading air bag is set on the outside of the sample, which can pressurize the side of the sample, but not the end of the sample, so that the undisturbed rock and soil cannot be compressed and restored to the initial formation stress state; in addition, the sample The two ends of the sample are in direct contact with the upper and lower cover plates, resulting in a friction effect at both ends of the sample, which in turn makes the radial deformation of the sample uneven

[0006] The Chinese invention patent "A Rock Side Friction Test Device and Method with Controllable Confining Pressure (Publication No.: CN105547841 A, Application Publication Date 2016.05.04)" discloses a rock side friction tester using a triaxial pressure chamber to apply confining pressure. The friction resistance test device and its method can be used to test the lateral friction resistance of the foundation pile and the rock interface under different confining pressures, but it is impossible to prepare samples according to the actual construction process of the pile foundation; in addition, after the confining pressure is applied, the vertical pressure passes through The guide tube acts on the top of the sample, and due to the difference in stiffness between the foundation pile and the rock, the two will produce a certain relative deformation, resulting in initial side friction at the interface between the two, which will affect the test results

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