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the assumption of the bi-linear force-displacement relationship. Such consistency is unreachabie only by
using the BST surface based on the idealized elasto-plastic assumption.
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CONCLUDING REMARKS
In summary, the shake table tests provided useful data references for theoretical studies on seismic
torsional effects of asymmetric building structures. Through the comparison between the experimental
and the theoretical results, the following conclusions can be obtained:
1) Although the BST (base shear-torque) surface established on the assumption of idealized
force-displacement relationship can be roughly used to estimate the seismic performance of
asymmetric systems, it will bring obvious error on the prediction of the nonlinear response when the
studied structure suffered strong earthquakes.
2) Therefore, based on the assumption of the bi-linear force-displacement relationship and the
displacement-based method to determine the stiffness, the state space signifying the base
shear-torque relationship is developed to describe the entire seismic capacity of the asymmetric
systems. It shows high consistency with the experimental results. Therefore, it is no doubt a reliable
model that can be directly used to estimate not only the entire seismic capacity but also the potential
seismic damage may occur in the studied systems, even without relying on any complicated
numerical analysis. It can be seen, this model will be very convenient and useful in evaluation of the
lateral-torsional coupling effects of asymmetric structures particularly in the preliminary stage of
design, retrofitting and research.
It should be noted that abovementioned conclusions are obtained on the basis of the experimental results
of single story building structure. Their reliability and universality should be checked further with real
seismic records or earthquake simulation tests for multi-story and high-rise building.
References
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