Research On Seepage Field Simulation And Monitoring Model Of Seawall Considering Rainfall

The stability of seawall is related to the safety of life and property within the scope of its protection.In order to master the real-time security status of the seawall engineering,the establishment of a scientific and effective monitoring model is of great significance.Among the many factors that influence the safety and stability of seawall,seepage pressure is an important index to judge seawall safety.The seawall is always affected by the tide level,so the tide level is the main factor affecting the distribution of seepage pressure;at the same time,seawall also often suffers from rainfall,so rainfall is an important factor affecting the distribution of osmotic pressure.Under the combined effect of tide level and rainfall,the seawall is in saturated-unsaturated unsteady seepage state for a long time,which is very easy to cause seepage damage and slope instability.Firstly in order to grasp the seepage field distribution of seawall in time,and monitor and analyze the safety and stability of seawall under special working environment effectively,this paper presents a relatively simple and accurate rainfall infiltration model based on the analysis and summary of previous studies.Secondly,using the ANSYS thermal analysis module,seepage field distribution is simulated by tide level as the head boundary condition and rainfall as the flow boundary condition respectively.The ANSYS Parametric Design Language is used to write seepage field analysis program.During the analysis,the free surface and the overflow point are adjusted according to the previous finite element iteration calculation,and the unsaturated zone permeability coefficient is modified by the matrix suction.Thirdly,both of the seepage field calculation of seawall without rainfall infiltration,and the seepage field of seawall under the collective action of tide level and rainfall are carried out in this paper during the study period.The results show that,the fitting results of the finite element method are in good agreement with the measured data when the rainfall infiltration model proposed in this paper is adopted.In addition,during the analysis of seepage unsteady seepage field,it can be found,that when the initial tidal level at different periods is adopted,the velocities of the simulated seepage field approximating the real seepage field are obviously different.Therefore,the velocities of the simulated seepage field approaching the real seepage field are also studied,when the initial tidal level is in four different periods.Finally,according to the finite element calculation results of seepage pressure at the monitoring points,the corresponding water head osmotic pressure component and rainfall osmotic pressure component are extracted,and the parameters of the two component expressions are evaluated separately,then the coefficients of the water head osmotic pressure components and rainfall osmotic pressure components are adjusted,all the parameters are estimated together with the aging components,thereby establishing the deterministic model of seepage pressure is established,which provides a reliable reference for the safety state of seawall.