Deformation Properties Of Soft Clay Ground Under Repeated Loading

Based on the summarization and statement of repeated loading mechanism and theory, deformation properties of soft clay ground under repeated loading was primarily studied through consolidation compressure test of repeated loading and test of instantaneous repeated loading and unloading indoor, combined with layerwise summation method for ground settlement.Firstly, summarized research actuality of soft clay ground deformation properties under repeated loading, introduced available mechanism of repeated loading, test achievements, calculation methods and the similarities and differences of them. Necessity of this thesis has been demonstrated.Secondly, according to the result of repeated loading consolidation test, qualitative analysis such things as changing rules of void ratio,coefficient of compressibility and consolidation under repeated circle, void ratio coefficient of compressibility and consolidation with increased loading in different form, and relationship of change of void ratio with repeated loading times.According to the test of instantaneous repeated loading and unloading, analysis the similarities and differences of the trend of void ratio along with time under repeated loading and unloading of 50kPa or invariable load of 50kPa of different soil under same pressure and same soil under different pressure. The conclusion is curves of void ratio with time tend to consistent in the end under repeated loading and unloading 50kPa or invariable load of 50kPa.Based on the quantitative analysis of relationship of the increment of void ratio and times, combined with layerwise summation method, suggested a formula for final settlement of soft clay under repeated loading, which considered the influencing factor of times of repeated load,over- consolidation ration,repeated consolidation pressure and initial void ratio .Finally, analysis the factors which had not been considered in this thesis in order to provide basement for more credible, available and convictive study in the future.