This study aims to rigorously examine the influences of the vertically propagating recorded strong ground motions on the trapezoidal-shaped hills in different sizes and shape ratios. In order to generalize the results of the study, one-dimensional as well as two-dimensional analyses are conducted. Then, intended results are represented in dimensionless form as a result of which amplification ratio patterns are extracted and compared with each other in terms of displacement, velocity, and acceleration. | JSEE Vol. 19, No. 4, 2017 Seismic Assessment of Trapezoidal-Shaped Hills Induced by Strong Ground Motion Records Masoud Amelsakhi1*, Abdollah Sohrabi-Bidar 2, and Arash Shareghi3 Received: 10/10/2017 1. Assistant Professor, Department of Civil Engineering, Faculty of Engineering and Technology, Qom University of Technology, * Corresponding Author; email: amelsakhi@ 2. Associate Professor, School of Geology, College of Science, University of Tehran 3. Department of Civil Engineering, Faculty of Engineering, Urmia University Accepted: 28/04/2018 AB S T RA CT Keywords: Topographic effect; Time-domain amplification ratio; Spectral amplification ratio, Geotechnical earthquake engineering This study aims to rigorously examine the influences of the vertically propagating recorded strong ground motions on the trapezoidal-shaped hills in different sizes and shape ratios. In order to generalize the results of the study, one-dimensional as well as two-dimensional analyses are conducted. Then, intended results are represented in dimensionless form as a result of which amplification ratio patterns are extracted and compared with each other in terms of displacement, velocity, and acceleration. Similarly, corresponding response spectra ratios are derived on significant points on hill-crest, hill-side, and beside of that, and juxtaposed in diagrams. Results of the assessment are put together with that of recent studies and predictions of the reliable codes. An adequate agreement between maximum values of amplification ratios obtained in time-domain analyses and spectral analyses makes us hopeful to think of connecting time-domain parameters with spectra-related ones to propose an accurate equation, which considers more effective variations regarding the topographic seismic effects and gives most reliable prediction. However, here, an equation has already been suggested to draw amplification ratio patterns on different points of the hill for a limited hillshape, .