In response to the 1933 Long Beach earthquake ( California ) the city of Los Angeles adopted the first earthquake design provisions enforced in the U.S. , enacted by City Council under Ordinance No. 72,968 published September 6 , 1933 . The requirements included a design lateral base shear V = 0.08 W for regular use buildings , 0.10 W for school buildings and 0.04 W for the portion of a building above a flexible story . Building weight ( seismic mass ) was defined as W = Dead load 0.5 Live load ( except 1.0 Live for warehouses ) . Building frames were required to be designed to withstand at least 0.25 V independent of any walls
1933 Long Beach earthquake
1933 Long Beach earthquake
Seismic code