The Earthquake Engineering Online Archive

Hybrid solution techniques for generalized pseudodynamic testing

Thewalt, Christopher R.; Mahin, Stephen A.

UCB/EERC-87/09, Earthquake Engineering Research Center, University of California, Berkeley, 1987-07, 142 pages (555.3/T49/1987)

The pseudodynamic method, previously applied to simple planar structures subjected to a single horizontal component of base excitation, is generalized for work with arbitrary structural configurations subjected to a fixed-base excitation with up to six components. The extended system of equations of motion is verified using both a three degree-of-freedom steel specimen tested on a shaking table and the pseudodynamic method. Practical observations on implementing and operating a pseudodynamic test system are given based on experience using the test system at the Univ. of California at Berkeley. Criteria to be used to determine the reliability of results from a given test are specified. A new formulation of the method that can be used to perform tests at or near real time is presented. The new technique uses force control and is suggested for testing structures composed of rate-sensitive materials. A new method is proposed that allows fully implicit integration methods to be used without requiring iteration or estimate of tangent stiffness properties. Verification tests are used to evaluate the method's stability and accuracy.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-87-09.pdf (5 MB)