Influence Of Flood Soaking On Bearing Capacity Of Unsaturated Expansive Soil Foundation

With the development of technological innovation in green livable villages and towns,the living standard of the people in villages and towns is improving day by day.Analysis of the effective function of foundation and foundation seepage in villages and towns is an effective research method of non-engineering measures for flood control and disaster reduction in villages and towns,which can effectively improve the overall level of flood control and disaster reduction of buildings in villages and towns in China.The research on flood risk assessment and analysis can effectively control and reduce the destructive effect of floods,ensure the safety of village buildings,reduce the economic and property losses caused by flood disasters,and have obvious economic benefits for the society.In view of this,based on ABAQUS,the seepage field analysis,fitting relation method,sequential coupling method and small strain method are used to analyze the seepage flow and calculate the vertical ultimate bearing capacity of unsaturated expansive soil foundation in existing villages and towns.Quantitative data such as the seepage change law of unsaturated expansive soil foundation and foundation and the vertical ultimate bearing capacity of strip foundation are given,and various parameter factors affecting the seepage field effect and the vertical ultimate bearing capacity are deeply discussed.In addition,the loss rate of village and town building flood disaster and the evaluation framework of flood disaster-causing factors based on analytic hierarchy process are constructed.Specifically,it includes the following research work:?1?The reliability of fitting relation method is systematically verified,the law of one-dimensional soil column soaking process is analyzed,and the change law of two-dimensional unsaturated expansive soil foundation-strip foundation under the action of transient and steady seepage is simulated.The calculated value obtained by numerical analysis is compared with the theoretical value obtained by literature investigation,which proves the correctness of the calculation process and the reliability of the calculation conclusion.?2?The parameters of the previous numerical analysis process are changed into variables,and the influences of the changes of important parameters such as Pore pressure POR,saturated permeability coefficient K_S,and initial saturation S_r00 on the seepage analysis process of unsaturated expansive soil foundation-strip foundation are quantitatively analyzed,and the relationship curves and fitting formulas of the indexes such as foundation vertical displacement,rotation angle and seepage flow with the changes of parameters are proposed.?3?The reliability of the small strain method is systematically verified,the in-situ stress balance method is expounded and the balance results are displayed.The small strain method and the sequential coupling method are applied to analyze the change of the vertical ultimate bearing capacity of unsaturated foundation-strip foundation before and after seepage,and are compared with the bearing capacity limit values calculated by literature investigation.Considering the influence of the change of initial saturation S_r0 on the vertical ultimate bearing capacity of strip foundation,at the same time,some pertinent engineering suggestions are put forward.?4?Taking village and town buildings as the research object,the evaluation method of flood disaster loss rate is discussed,and the disaster-causing factors of flood disaster are taken as the research object,and the hierarchical evaluation of disaster-causing factors is carried out based on the principle of analytic hierarchy process.