Cumulative Plastic Strain Prediction Model for Silt in Different Regions
During the long-term service of airport subgrade,the development of cumulative plastic strain of silt in different regions is significantly different.The regional differences of silt are seldom considered in current studies.The current prediction models rarely quantify and predict the roadbed siltation uniformaly for different regional airports.To determine the key influence indicators affecting cumulative plastic strain of silt,predict the plastic strain of silt in different regions,and ensure the long-term service performance of subgrade,the study took soil from the silt subgrade of 3 different airports in North China.The dynamic triaxial tests of silt in different regions and with different clay contents were carried out,which revealed the development of cumulative plastic strain of silt in different conditions,and investigated the mineral composition of silt in different regions through the SPSS grey correlation analysis.Through SPSS grey correlation analysis,the correlation among mineral composition,grain composition,liquid-plastic limit,optimum water content,and maximum dry density of silt in different regions and the final cumulative strain under cyclic loading were investigated.The clay content was finally determined as the key evaluation indicator.The prediction model of final cumulative plastic strain was established on the basis of test results.The result indicates that there are significant differences in grain composition,liquid-plastic limit and maximum dry density of silt in different regions.The cumulative plastic strains under cyclic loading also differ significantly,and are affected by dynamic stresses.Through the grey correlation analysis,the viscous grain content is determined as the quantitative indicator for evaluating the final cumulative plastic strains of silt in different regions.Based on the result of dynamic triaxial tests with different clay contents,the prediction model of final cumulative plastic strain considering regional differences and amplitude of dynamic stress was established.The prediction model can be applied to different regions of airport subgrade silt.Based on the local silt clay content,it can accurately predict the cumulative plastic limit strain during long-term service.
NETL
NSTL
万方数据
