Damage response of multistorey r/c buildings with different structural systems subjected to seismic motion of arbitrary orientation

Abstract

SUMMARYIn the present study the combined influence of seismic orientation and a number of parameters characterizing the structural system of Reinforced Concrete (R/C) buildings on the level of expected damages are examined. For the purposes of the above investigation eight medium-rise buildings are designed on the basis of the current seismic codes. The structural characteristics examined are the ratio of the base shear received by the structural walls, the ratio of horizontal stiffness in two orthogonal directions and the structural eccentricity. Then, the buildings are analyzed by nonlinear time response analysis using 100 bidirectional earthquake ground motions. The two horizontal accelerograms of each ground motion are applied along horizontal orthogonal axes, forming 72 different angles with the structural axes. The structural damage is expressed in terms of the Park and Ang damage index. The results of the analyses revealed that the damage level of the buildings is strongly affected by the incident angle of the ground motion. The extent at which the orientation of the seismic records influences the damage response depends on the structural system and the distance of the record to the fault rupture. As a consequence, the common practice of applying the earthquake records along the structural axes can lead to significant underestimation of structural damage. Also, it was shown that the structural eccentricity can significantly differentiate the seismic damage level, as well as the impact of the earthquake orientation on the structural damage.

An Efficient Method for Considering the Directionality Effect of Earthquakes on Structures

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“…Magliulo et al, based on 3 multistory reinforced concrete (RC) buildings and using both roof displacements and plastic hinge rotations as Engineering Demand Parameters (EDPs), showed that there is an increase of up to 37% for rotated records. Kostinakis et al studied 8 mid‐rise RC buildings of various structural systems and found the damage level to be strongly affected by the orientation to a degree that is a function of the structural system, the eccentricity, and the distance of the record to the fault rupture. Nievas and Sullivan highlighted the different levels of orientation influence with respect to structural typology, while Taskari and Sextos proposed the derivation of multiangle fragility curve for bridges.…”

Rapid Prediction of Seismic Incident Angle's Influence on the Damage Level of RC Buildings Using Artificial Neural Networks

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