Abstract: SHAKE has been widely used by engineers to predict ground responses in seismic design. Although SHAKE analysis is simple and straightforward, to generate accurate and reliable output still requires significant experience and skills; especially with regard to the significant uncertainty of soil parameters in ground response analysis. These uncertainties come from a number of factors such as initial shear modulus (or maximum shear modulus), dynamic shear modulus degradation curves, damping curves, and the existence of soft layers. For large infrastructure analysis, the results of ground response analysis have an important influence on the economy and safety of the whole design. Therefore we propose to perform a systematic sensitivity analysis to account for the uncertainties. Based on the results from these analyses, a systematical and rational way for researchers and industrial designers to carry out reliable ground response analyses is suggested.

Key words: seismic design, ground response analysis, earthquake, SHAKE, soft soil