ABSTRACT
The standards of construction are regulated by the earthquake-resistant regulations of building codes. The Committee on Seismology, National Academy of Sciences,928 has summarized the general principles that govern the preparation of an earthquake-resistant building code. All codes are in a constant state of development and improvement. Ground motion is the principal force mechanism addressed by the seismic provisions of a building code. This is the earthquake hazard usually responsible for the greatest losses to the works of construction. One of the most important elements of an earthquake-resistant structure is its plan and elevation configuration. The optimum choice is a symmetrical configuration, such as a square cube, because the induced vibrations and displacements will be uniform or nearly so during an earthquake. The technique permits engineers to analyze the impact of ground motions on their proposed designs and suggests ways in which seismic-resistant design can be optimized.
