This paper examines the wall and column wall ratios of low-rise RC buildings to determine wall and column wall ratios that would limit the degree of building damage to a level no greater than slight damage for the purpose of continued use of the building after a mainshock, foreshock, or aftershock. Based on the energy balance in seismic response, a simple evaluation formula was derived to calculate wall ratio to a strength that would allow walls to withstand a level of damage up to shear cracking after an earthquake. The applicability of this formula was confirmed by comparing the wall ratio of actual buildings based on earthquake damage surveys with the results of this evaluation formula. The results indicated standards for wall and column wall ratios that enable buildings to withstand being hit by one to three earthquakes of an extremely rare level, as described in the notice, and still sustain a level of damage below shear cracking.
