Dynamic Properties and Earthquake Response of Hardpan

For the need of earthquake microzonation some studies on the dynamic properties of hardpan in west Anhui were conducted. The microstructure of hardpan is described through observation of electronic microscope and its effect on the mechanical properties is analyzed. From the shear wave velocity by boring and dynamics triaxial test the relation of shear stress-strain confirms to hyperbola, and the shape of hyperbola depends on the state of fissures distributing in hardpan. Earthquake dynamic response of stratum was calculated by lwan model and relation of site response spectrum to the stratum condition was analyzed. Finally, earthquake force based on maximum site acceleration and response spectrum to different design criterion for different type of site was determined.