A low computational cost seismic analyses framework for 3D tunnel-form building structures

Abstract

Numerical modeling of tunnel-form buildings entails the utilization of 3D finite element models consisting of large numbers of shell and fiber elements. Accordingly, the non-linear analysis of such models under seismic excitations is both time-consuming and computationally expensive, especially in the case of large scale structures. To address this challenge, this study investigates the efficiency of the Endurance Time Method (ETM) to evaluate the structural responses, location of damage initiation, and the overall performance of tunnel-form structures under the Design Basis Earthquake (DBE) hazard level. Comparison with results derived from pushover and time-history analyses indicated the acceptable accuracy of ETM with significantly less computational efforts. The computation time required for the ETM was less than 25% of pushover (until total failure of the system) and time history analyses on the five- and ten-story tunnel-form buildings. The maximum differences between the results of ETM and time history analysis used to estimate the story drifts and shear forces were 4–6% and 1–4.5%, respectively. Considering the reliability of ETM and its appropriate accuracy, this method can be considered as a suitable alternative to the conventional methods to provide a low computational cost seismic analyses framework for non-linear tunnel-form buildings and similar structural systems.