A multi-parameter micro-test device for simulating dry-wet cycle and its application method

Abstract

The invention discloses a multi-parameter micro-testing device for simulating a dry-wet cycle and a using method thereof, and relates to the technical fields of soil mechanics and geotechnical engineering, the multi-parameter micro-testing device includes a box body, a base, a soil sample box and a control panel, and the multi-parameter micro-testing device also includes a measuring system, a sampling system, a dry and wet circulation system and a displacement control system which are connected with the control panel; hot air generated by a hot air generating device and humid steam generated by an ultrasonic steam generating device are pressurized by a turbo pressurizing device and then enter from the soil sample box to a soil sample, at the same time, the change of water content in the whole process can be detected through optical fiber, and the control of the wet and dry cycle can be realized. The multi-parameter micro-testing device has the beneficial effects that a micro-static sounding probe can measure the penetration resistance of a soil conical tip, a cross shear plate can measure the undrained shear strength and shear modulus of the soil sample, the relationship between the micro-static sounding probe and the cross shear plate can be analyzed by testing of a specific soft soil sample. The multi-parameter micro-testing device can provide a most simple and feasible solution for calculation of the shear strength of on-site soil by static penetration testing.

Description

technical field [0001] The invention relates to the technical fields of soil mechanics and geotechnical engineering, in particular to a multi-parameter micro-test device for simulating dry-wet cycles and its use. Background technique [0002] At present, there are generally three methods for calculating the undrained shear strength of soft soil: one is the on-site cross-plate shear test, which is the main field test method, but it is often limited by site conditions. It cannot be implemented, the test process is complicated and time-consuming, and the test results are also affected by factors such as burial depth and shear velocity; the second is the indoor unconfined compressive strength and triaxial shear test. This method is often due to soft soil sample sampling, Influenced by factors such as difficulty in sample preparation, the experimental results are also affected by the quality of the sample, and the inaccuracy is relatively large; the third is to use the static pen...

AI Technical Summary

Problems solved by technology

[0003] In the past, when testing the basic strength and deformation characteristics of the soil, only a single index of the soil can be tested each time, such as the compressive modulus of the soil, the undrained strength of the clay, the side friction resistance, the shear strength or the shear modulus. etc., there is no test equipment for comprehensive measurement of multiple parameters for the same sample

[0004] In the past, in the indoor static penetrating test of soil, usually only the cone tip resistance was measured, without considering the influence of side friction resistance, and the obtained test data was not accurate.

At the same time, due to the lack of real-time monitoring of pore water pressure during the penetration process, it is impossible to make reasonable corrections to the resistance of the cone tip, and the resistance of the cone tip cannot reasonably reflect the mechanical properties of the soil, and it is impossible to evaluate the seepage and consolidation characteristics of the soil.

The reliability of soil stratification and soil classification cannot be guaranteed

[0005] In the past, the cross-plate shear test was used to test the undrained shear strength of the field soil. The cross-plate shear tester developed for the indoor test is often not designed according to the change of the shear strength index of the expansive soil during the dry-wet cycle. , so the shear strength of the same soil sample under different drying and wetting cycles cannot be provided

[0006] In the past, synchronous sampling was not set during the indoor test, which made the analysis of the test results lack of basis, and the current basic physical properties of the soil could not be monitored and fed back.

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