TEST RESEARCH ON DYNAMIC BEHAVIOR OF GEO-GRID REINFORCED CLAYS

Based on unconsolidated undrained dynamic triaxial compression test,the reinforced clays were researched.Test results proves that disposing reinforced geo-grid material in clay can increase its dynamic shear strength.The more reinforced geo-grid layers is,the bigger dynamic strength is.Reinforced dynamic reinforcement effect can be better to play on high confining pressures.The dynamic reinforcement effect of reinforced clays with geo-grid reflect just on increasing of dynamic cohesion,but almost no influence on increasing of the dynamic friction angle.Cycle times of dynamic vibration force had little impact on dynamic strength index.The cycle dynamic stress amplitude exert a tremendous influence on reinforced deformation.The deformation increases quickly under large cycle dynamic stress,the sample destructs in smaller vibration times.Conversely,the sample destructs in larger vibration times under small cycle dynamic stress.There is a critical damage dynamic stress,when the setting dynamic stress amplitude is less than the dynamic critical stress,regardless of how many vibrating times,sample can not attain to damage strain,and when the dynamic stress amplitude is too large,the sample is instantaneous destroyed on the beginning vibration.