It’s a directional thing. The Indian Plate moves horizontally north, sliding under the Asian, with nominal vertical motion. Someplace to the north there was probably vertical “bucking” similar to the Fukushima and the Banda Aceh which were vertical motion. It’s clear from the pics available so far that the primary motion was sideways-—just basically flinging the buildings sideways. One can only design for that by making a pretty good guess which way the shove is coming from. Incidentally, the roadway pics I’ve seen show much more sliding sideways than bucking.