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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
NONLINEAR STATIC ANALYSIS METHOD BASED ON
DISPLACEMENT
Tu Wen-ge and Zou Yin-sheng
Department of Civil Engineering, Hunan University, Changsha, China, 410082
ABSTRACT
In this paper, nonlinear static method based on displacement is presented. The earthquake-resistant
performance of a building structure is represented as a sequence of functions of the maximum
displacements that occur during strong seismic ground motions. The acceleration of ground motion
being monotonously increased step by step, maximum displacements can be estimated using the
concept of elastic displacement (or acceleration) spectra and be distributed using SRSS. These spectra,
together with recently proposed natural periods for frame structures being into inelastic range, are then
incorporated into a nonlinear static method based on displacement. Tow examples illustrate the
proposed method.
INTRODUCTION
Traditional earthquake-resistant design methods emphasize that adequate strength, instead of
displacement, is considered as the main design parameter. In the design procedure, the structural
response of maximum base shear based on an elastic spectrum analysis is placed computation of and
considered to be adequate; and then the member sizes are calculated via the distribution of this
maximum base shear, based on elastic strength demand, along the height of the structure. Traditional
methods do not explicitly consider the effects of ground motions' duration and the effects of hysteretic
behavior of structural members, which will affect the overall force and deformation patterns on the
structures. The above effects are implicitly considered by means of checking displacement limits (even
extending to inelastic range) after sizing the structural members from the calculated elastic forces.
In the case of large earthquakes, when yielding occurs in a structure and the structure is into inelastic
range, the structural inter-storey drift increase more quickly than inter-storey shear, and structural
members' deformation increase more quickly than members' force. Besides, it has been proved in