A test method and device for indoor measurement of soil porosity

Abstract

The invention belongs to the technical field of geotechnical engineering, and in particular relates to a test method and device for measuring soil porosity indoors. The test device comprises a soil body sample, a drying oven, a drying box, a sandbath and soil particle specific gravity bottle, an electronic scales, a rubber membrane, a rubber membrane sealing band, a one-way air extracting valve, an air extracting cylinder, a digital tautness meter, a concave container, a thin filament and a cylindrical container. Compared with the prior art, the test method and device for measuring soil porosity indoors, provided by the invention obtain the porosity of a soil sample according to parameter water content, specific gravity of soil particle and a difference of two times of data of the tautness meter which are obtained in the test; according to the method and the device, density measurement on soil is avoided, by directly starting with mass and density which are easiest to measure, the porosity is directly calculated, so the result is more accurate, the defect of big error of a current method is overcome, and the practicability is very high.

Description

technical field [0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a test method and device for indoor measurement of soil porosity. Background technique [0002] Soil porosity is the basic physical parameter of soil and an important parameter for analyzing the characteristics of soil in laboratory experiments. At present, there are very few methods for analyzing soil porosity, and the conversion method is generally used for analysis. The specific steps are: first, measure the dry density and specific gravity of soil particles, and then use the formula n=1-[ρ d / (G s ·ρ w )]Calculation. Among them, n is the porosity of soil; ρ d is the dry density of the soil sample; G s is the specific gravity of soil particles; ρ w It is the density of pure water at 4°C, generally 1g / cm 3 . In the formula, the density of pure water is a fixed value, and the density of soil particles has high accuracy and efficiency in labor...

AI Technical Summary

Problems solved by technology

The current indoor dry density measurement method of soil samples is mainly based on the ring knife method, but the ring knife method is not accurate enough. Inhomogeneous samples cannot be tested; 2) The soil sample is compressed during the sample preparation process of the ring knife method, which affects the test index; 3) It is difficult to ensure that the soil sample surface and the ring knife edge surface are completely intact when removing the remaining soil at both ends. Flush; 4) reciprocating smoothing of the soil sample affects the quality of the sample

These four problems seriously affect the authenticity and accuracy of the density, which indirectly leads to the distortion of the porosity of the soil

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