This research program will investigate the effect of local soil conditions and topographic changes on earthquake-induced strong ground motion and the resulting damage to buildings. For example, accelerograph records show that much greater intensities of shaking occurred in those parts of Mexico City underlain by relatively deep layers of soft clay as compared to other parts of the city underlain by stiff soil deposits or rock-like conditions. It is also believed that local discontinuities in soil conditions, such as the proximity of Metro stations and tunnels, highway underpasses, and stiff soil interfaces, resulted in a significant local amplication of the ground motions.
