The Study On Resilient Modulus Taking Into Account Theoretics Of Unsaturated Soils

The filled soils of highway subgrade, compacted soils, is representative unsaturated soils. The principal character of unsaturated soils is related to that water pressure of hole is negative value, being different from saturated soils. It draw forth a important mechanics parameter-matric suction that unsaturated soils differentiates in saturated soils from this.Resilient modulus of highway subgrade is the main mechanics parameter that reflects roadbed resisting deformability. The definition of resilient modulus shows the relationship of load and resilient distortion in part static load effect. In order to treat with design of roadbed and road surface structure, containing design of the roadbed drain accurately, resilient modulus should be located an important palce. At present, the study of resilient modulus is focusing on influencing rule of mainly influencing factors and correlativity studies of other physical or mechanics parameter of roadbed soils as well as the research of testing principle, method and standard etc.. The study that has been discussed above is based on soil mechanics of saturated soils.Through indoor experiments in the paper, influencing factors of unsaturated soils have been studied. Making use of pressure board apparatus, author has carried through Contrastive studies on soil-water characteristic curve that reflect the relationship of water content and matric suction and brought forward regressive equation of soil-water characteristic curve convenient for project application. Furthermore, author have studied the impact of moisture circulation process on resilient modulus. At the same time, it has been pointed out the method of acquiring resilient modulus taking into account moisture circulation. Finally, author suggest the value of resilient modulus being grounded on the theory of unsaturated soils.The paper apply the theory of unsaturated soils to the study of resilient modulus, the parameter of stress and strain property, first. The method and means of relevant studies have broken through that before now to some extent. Obtained achievement in the paper may be used for design and construction of subgrade and road surface or prevention and cure of highway disease directly. In a word, the study of this paper have important academic significance, real application value and hopeful prospect.