A soil body volumetric water content testing method based on electromagnetic wave time domain reflectometry

Abstract

A soil body volumetric water content testing method based on electromagnetic wave time domain reflectometry is disclosed. The method includes preparing 3-5 soil body samples with different dry densities, measuring a series of gravimetric water content standard values, gravimetric water content equivalent values w by the electromagnetic wave time domain reflectometry and the dry densities, fitting to obtain a linear regression function about gravimetric water content relative errors [Eta] and the corresponding soil body dry densities [Rho]<di>, with the function being [Eta] = a[Rho]<di> + b, acquiring a water content standard value of a soil body and a calibration coefficient [Zeta] of an electromagnetic wave time domain reflectometry measuring value, with the [Zeta] being equal to 1-a[Rho]<d>-b, measuring a volumetric water content [Theta] of the soil body to be tested by using the electromagnetic wave time domain reflectometry, and further acquiring a calibrated volumetric water content [Theta]' of the soil body by the electromagnetic wave time domain reflectometry, wherein the [Theta]' is equal to [Zeta]*[Theta]. The method eliminates influences of different soil body types and dry density changes on volumetric water content testing by electromagnetic wave time domain reflectometry, obviously reduces test result errors and is accurate and reliable in test results, thus providing more accurate and more reliable test parameters for geotechnical engineering designing and construction.

Description

technical field [0001] The invention relates to a method for testing the water content of soil, in particular to a method for testing the water content of soil volume based on the electromagnetic wave time domain reflection method. Background technique [0002] Moisture content is an important parameter in geotechnical engineering, and it is crucial to the property evaluation, stability analysis and compaction quality control of geotechnical engineering such as roadbeds, slopes, dams, and foundations. The drying method is the standard method for measuring moisture content in the current norms. The method is: put the soil sample in an oven, keep the temperature of the oven at 105-110°C, and calculate the water loss after the water in the soil sample evaporates. Get the moisture content of the soil. The moisture content measured by this method is more accurate. However, in the on-site test, the drying method requires drilling and sampling, which has problems such as sampling...

AI Technical Summary

Problems solved by technology

For example, when the soil matric suction is determined according to the soil-water characteristic curve, a small change in soil moisture content will cause significant errors in the calculation results of the matric suction.

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