Experimental Study On The Moistening Deformation And Moistening Strength Of The Unsaturated Expansive Soil

Expansive soil has the characters of swell shrinking, overconsolidation, fissure and reducing shear strength so that it is considered as one of the world's difficult problems and is taken seriously in geotechnical engineering field. Though it has been studied for many years, there are still many problems to be solved urgently due to the complexity of it. This paper, based on the item"948"sponsored by Ministry of Water Resources P. R. China, studies the moistening deformation and moistening strength of the unsaturated expansive soil in Ankang. First of all, a great deal of the research achievements in the field is consulted, and every fruit main contribution and defect is evaluated. It's realized that the cardinal nature of expansive soil is its special sensitivity to water and the task of this paper is to study the deformation and strength of expansive soil regular pattern because of water content increasing.The tests are done by using compressed instrument on the immersion deformation of expansive soil with different initial dry density, different initial water content and loading immersion paths. Based on the tests, factors affecting immersion deformation such as different initial dry density, different initial water content, immersion water content and loading immersion paths are analyzed and the deformation patterns with expansive soil in the lateral restraint condition are discovered. Furthermore, it's found out that pressure inhibits swelling deformation obviously and subtracting expansive rate is proposed.The triaxial apparatus is reformed for doing tests on immersion deformation; the pore water pressure and deformation can be determined using the instrument. The experimental method of moistening deformation about unsaturated expansive soil is put forward referring to the experiment on the moistening deformation of loess and deformation regular patterns of expansive soil are concluded for the effect of both force and water by doing lots of experiments.The experimental method of moistening shear on expansive soil is give with reference to...