Volume 25, Issue 2 (June 2002)
Experimental and Data Analysis Techniques Used for High Strain Rate Tests on Cohesionless Soil
Experimental methods used to subject drained triaxial compression axisymmetric test specimens composed of cohesionless soils to very high strain rates and analyze the resulting data are presented. Included is the use of a custom gravity drop-frame loading system to generate the high strain rates and a custom square triaxial cell to minimize optical distortion. Methods to collect and analyze the experimental results are also presented. High-speed film photography, coupled with digital image analysis techniques, are used to capture specimen deformations. Experimental issues such as image analysis of specimens, optical corrections, time synchronization of photographic images with data acquisition, inertial effects, global versus local strain measurements, axisymmetric shape of the specimen during deformation, and membrane compliance are examined by analyzing test results that were performed at high strain rates.