Displacement Estimation of Elastic Structures with Unbalanced Stiffness Using Energy Approach

ABSTRACT

This paper describes methods to estimate the peak seismic displacements of elastic structures with different stiffnesses in each direction. An energy approach is used to estimate these displacements as a function of the stiffness difference and period. It is shown that (a) the peak displacement in the stiffer direction can be predicted by the spectral displacement associated with the period in that direction, (b) the likely displacement in the opposite direction can be estimated from the displacement in the stiffer direction using energy considerations irrespective of the level of damping or period. This approach is illustrated by a design example.

KEYWORDS:

• Peak seismic displacements
• elastic structures
• energy approach
• unbalanced stiffness structures
• time history analysis
• spectral displacement