title: A focused electric spark source for non-contact stress wave excitation in solids.
abstract: A focused electric spark is used as a non-contact acoustic source to excite stress waves in solids. The source consists of an electric spark source located at the near focus of an ellipsoidal reflector that focuses the acoustic disturbance generated by the spark source to the far focal point. Experimental studies using both contact and non-contact sensors indicate that the source has the capability to excite the Rayleigh surface wave and impact-echo mode (S1-zero-group-velocity Lamb mode) in a 250 mm thick concrete slab and to enable fully air-coupled testing of concrete specimens.
authors: Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, Texas 78712 xdai@utexas.edu, jyzhu@mail.utexas.edu.
authors: Xiaowei
authors: X
authors: Dai
authors: Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, Texas 78712 xdai@utexas.edu, jyzhu@mail.utexas.edu.
authors: Jinying
authors: J
authors: Zhu
authors: Applied Research Laboratories, The University of Texas at Austin, P.O. Box 8029, Austin, Texas 78713-8029 haberman@arlut.utexas.edu.
authors: Michael R
authors: MR
authors: Haberman