Study On The Mechanical Properties Of The Resistivity Of Hefei Expansive Soil

The problem of expansive soil is one of the most complicated problems in the field of engineering geology, and the problem of mechanical properties of expansive soil has not been solved very well. Expansive soil is widely distributed in our country, therefore, based on the practical engineering, it has great academic value and practical value to study the mechanical properties of expansive soil.In this paper, the expansive soil in Hefei has been used as the research object. Through a large number of laboratory tests, and under the conditions of different water content and wetting-drying cycle, the unconfined compressive strength-resistivity test and consolidation-resistivity test were carried out. The main conclusions of this paper include: The unconfined compression strength of expansive soil is inversely proportional to water content.Remolded soil and water content has a good linear relationship, the relationship between undisturbed soil and water content is complex. The unconfined compression strength is inversely proportional to wetting-drying cycles. There are three kinds of effects which lead to the change of resistivity during the compression process of expansive soil, and they are compaction effect, water connection effect and structural damage effect. The different change of resistivity of expansive soil samples are the superposition and comprehensive reflection of these three effects. In the course of the experiment, the void ratio of expansive soil has the same variation law with the resistivity. First, both of them decreased rapidly, and then continue to reduce, but the amplitude becomes slow, finally to maintain stability. The compression modulus decreases with the increase of water content, and show a linear relationship. The compressive modulus and the initial resistivity have a good logarithmic relationship.The research results are helpful to explore the strength of expansive soil by using electrical resistivity method, and establish the relationship and brige between earth's physical parameters and strength characteristics.