A New Method for Measuring the Soil-Water Retention Curve of Red Clay

Abstract:

Red clay is normally used in the area of Guangxi for roadbed filling and slope overburden. The engineering properties of red clay are closely related with the hydraulic characteristics. A new rapid method is adopted for measuring the soil-water retention curve of the red clay based on the dynamic multi-step outflow tests. The static soil-water retention curve is obtained through the non-equilibrium changes of soil-water under each step of matric suction. Compared with the traditional measured methods, the new method can save much time for determining the hydraulic characteristic functions, especially for clay soils. Several experiments are done under different suction steps and load time on the same red clay sample for verifying the effectiveness of the new rapid method. The experimental results show that the static soil-water data are largely dependent on the initial several suction steps and load time in the dynamic multi-step outflow tests. If the suitable loading scheme is adopted in the dynamic multi-step outflow method, the time can be saved greatly for obtaining the soil-water characteristic curve and hydraulic conductivity function of red clay. The significance of the rapid method will great for the engineering design and evaluation related with unsaturated red clay.

• Periodical: Advanced Materials Research (Volume 815)
• Pages: 796-802
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.815.796
• Online since: October 2013
• Authors: Pan Chen, Chang Fu Wei
• Keywords: Multi-Step Outflow, Non-Equilibrium Flow, Rapid Method, Red Clay, Soil-Water Retention

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