Cause Analysis Of Cracks On The Concrete Pavement Of The Embankment Based On Field Monitoring And Finite Element Analysis

Based on the consolidation-creep theory,this paper analyzes the settlement mechanism of soft soil foundation,and starts from the actual project to monitor the settlement of the dike,and analyzes the data in depth to grasp the dike settlement process and the law of settlement changes.Through drilling and core sampling,the laboratory test was used to obtain the parameters.Using PLAXIS software,the construction process of Yigong dike was simulated,and the influence of various factors on the cracks of the concrete pavement on the dike was analyzed.The main conclusions are as follows:(1)Based on the analysis of the mechanism of cracks,combined with the analysis of the current status of the Yigong embankment project,hydrogeology and surrounding construction,the results show that the Yigong embankment foundation is a soft soil layer,and under the influence of the load,the embankment foundation is easy to produce Consolidation and deformation problems;changes in groundwater and the setting of impervious walls have a role in promoting settlement and consolidation of the levee foundation.(2)Through the analysis of on-site monitoring data,the results show that the displacement of the monitoring point outside the dike top has a tendency to move out of the dike,and the vector displacement direction of all points on the inside of the dike top,the second slope,and the pressure immersion platform point into the dike.By comparing the monitoring data results and simulation analysis results,it is found that the embankment has a strong correlation with the water level of the outer river.The water level of the outer river affects the settlement of the top of the embankment,and the body of the embankment will change accordingly as the water level of the outer river rises.(3)Based on the finite element PLAXIS software,the internal stress of the dike,seepage prevention wall,excess pore water pressure,overload,groundwater level and earthquake are analyzed.The results show that the settlement deformation mainly occurs in the newly filled area inside the dike top,At the impervious wall and the second slope platform,and after 31 years of settlement of the embankment,the secondary consolidation has not been completed;the setting of the impervious wall prolongs the settlement consolidation,making it possible for the two sides of the impervious wall to crack,and It shows that the inside of the embankment cracks first,and the outside of the embankment also has a tendency to crack;the settlement,deformation,and even cracking of the embankment foundation are mainly caused by the secondary consolidation settlement(Ss)of the sensitive soil layer of the embankment;the overload setting makes the original stable The embankment re-enters the settlement and consolidation stage,which causes differences in settlement and consolidation of various parts of the embankment body(base),resulting in uneven settlement of the embankment;changes in groundwater level have a greater impact on the consolidation of the embankment,and the decline of the groundwater level will Accelerate the settlement of the embankment.The earthquake has no obvious impact on the stability of Yigong dike,but has a certain impact on the settlement of dike foundation.(4)Taking Yigong Embankment in Lushan District,Jiujiang City as an example,the PLAXIS software was used to simulate the construction process,and the calculation results of the layered sum method were compared with the simulation prediction results.The results showed that there was settlement on the waterfront and backwater sides of the embankment.Differences,and the dike has a tendency to continue to settle.The comparison between the monitoring results and the finite element analysis results verifies the rationality of the model and the factors causing the cracks in the dike.The results show that the water level of the Yangtze River has a strong correlation with the measured results and simulated settlement results of each monitoring point.The finite element model is basically reasonable;new Factors such as the nature of the fill soil,the setting of the seepage prevention wall,and the uneven distribution of the thickness of the weak soil layer of the embankment affect the settlement of the embankment,resulting in cracks on the pavement roof.