Triaxial free rock-soil dilatometer

Abstract

The invention discloses a triaxial free rock-soil dilatometer. A telescopic petal mold cylinder is arranged in the middle of a pressure chamber, the outer side of a sample is wrapped with a rubber membrane and connected into the telescopic petal mold cylinder in a sleeved mode, a bottom plate and a bottom permeable stone are sequentially stacked on a base, the bottom of the sample is supported onthe bottom permeable stone, and a top permeable stone and a top plate are sequentially pressed on the top of the sample; the top cover is provided with a top cover valve and connected with a piston through a piston spring, the bottom of the piston is in contact connection with the top plate, the top dial indicator is connected to the top displacement rod in a pressed mode through a top dial indicator support, and the upper portion and the lower portion of the telescopic petal mold barrel are symmetrically sleeved with displacement rings.The bottom of the petal mold cylinder is slidably connected to the base. A bottom plate water passing valve, a top plate water passing valve and a base water passing valve are arranged on the side face of the base and communicated with the bottom plate, thetop plate and the water tank respectively. The triaxial free rock-soil dilatometer is simple in structure, safe and stable, can well protect the sample when the sample is soaked in water and saturated through the telescopic petal mold cylinder, can flexibly adapt to expansion deformation of the sample, and is high in detection efficiency and accuracy.

Description

technical field [0001] The invention relates to a dilatometer, in particular to a rock-soil triaxial free dilatometer. Background technique [0002] In geotechnical engineering, the indoor testing of rock and soil mass is often carried out by the triaxial test method. The samples used in the triaxial test are generally cylindrical, so the triaxial sample saturator used is generally cylindrical, and the saturator is fixed. For general rock and soil mass, the volume change of the sample after soaking and saturation is small, and the general saturator can better meet the requirements of rock and soil mass saturation, but for rock and soil samples with high expansibility, such as expansive soil Because the mineral composition of the rock / rock is mainly montmorillonite, the sample will have significant expansion deformation after soaking in water, and will generate a large expansion pressure on the saturator. The use of a general saturator may cause radial stress on the expansive...

AI Technical Summary

Problems solved by technology

[0002]In geotechnical engineering, the indoor testing of rock and soil mass is mostly carried out by triaxial test method, and the samples used in triaxial test are generally cylindrical, so the three The axial sample saturator is generally cylindrical, and the saturator is fixed. For the general rock and soil mass, the sample volume changes little after being soaked and saturated. The general saturator can better meet the requirements of rock and soil mass saturation. , but for rock and soil samples with high expansibility, such as expansive soil / rock, because the mineral composition is mainly montmorillonite, the sample will have significant expansion deformation after soaking in water, and will generate a large expansion pressure on the saturator. Ordinary saturators may cause expansive soil / rock samples to change radially due to the constraints of the saturator, resulting in excessive deformation in the axial direction, and after the saturator is removed, the constraints will be removed and the samples will have a certain degree of deformation. Expansion and deformation may also be due to the excessive expansion force of the sample when it is saturated and damage the saturator. If the sample is directly immersed in water for saturation without using a saturator, the expansive soil / rock sample will easily swell and crack or even disintegrate and fall off. damage caused by the failure of the test

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