This award will fund the purchase of a SSH-100 Simple Shear System manufactured by GCTS Testing Systems of Tempe, Arizona. It will be supplemented and modified to allow it to perform cyclic triaxial testing and resonant column testing of soils, as well as cyclic simple shear testing. The cyclic shear apparatus will be the centerpiece of a research program to evaluate the effects of load path on energy-based pore pressure generation models. Energy-based pore pressure generation models can be used to help engineers predict how a soil mass will respond during an earthquake. In order to apply an energy-based pore pressure model to a specific soil, soil-specific parameters are determined by testing a specimen in a lab test, most commonly a cyclic triaxial test. These parameters allow the model to link the pore pressures generated in the specimen during loading to the shear energy dissipated in the soil. The question facing the users of energy-based models is whether the model developed is only valid for the loading conditions used to develop it (i.e., the load path applied by the test used), or if it is independent of loading conditions used and dependent only on the amount of energy dissipated. The PI?s research will use the SSH-100 Simple Shear System to quantify and clarify the effects that load paths have upon pore pressure generation in soils.
In addition to the specific research described above, acquiring this instrumentation will improve the PI?s ability to obtain both internal and external funding for research projects and to continue to provide research opportunities for undergraduate students. Acquisition of the cyclic simple shear device will put the PI in a strong position to obtain funding through collaborative proposals that make use of Valparaiso University?s increased research capabilities.
