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Seismic responses of high-rise buildings are dominated by the first few vibration modes; therefore, high-floor responses contain long predominant vibration periods. However, it may not be achievable to investigate the seismic performance of nonstructural facilities at high levels of high-rise buildings in the laboratory by using seismic shake tables because of the actuator stroke limitation. In this study, an advanced control strategy that incorporates a transfer system with modern control algorithms is proposed for shake tables to replicate high-floor responses of high-rise buildings subjected to earthquakes. First, design diagrams are proposed to determine the parameters of the transfer system. Then, a set of friction pendulums is adopted as the transfer system for the proof-of-concept stage. A mathematical model for the set of friction pendulums is developed for numerical studies prior to real experimental validation. Three linear controllers and three nonlinear controllers are designed and synthesized to verify the feasibility and applicability of the proposed strategy. Finally, the friction pendulum set is installed on a uniaxial shake table to replicate the roof responses of a 34-story building subjected to historical earthquakes. Experimental results demonstrate the proposed control strategy successfully replicates floor responses of the high-rise building that cannot be achieved formerly. [ABSTRACT FROM AUTHOR]

Many existing reinforced concrete (RC) structures around the world have been designed to sustain gravity and wind loads only. Past earthquake reconnaissance showed that strong earthquakes can lead to substantial damage to non-seismically designed RC buildings, particularly to their beam-column joints. This paper presents a novel retrofit method using buckling-restrained haunches (BRHs) to improve the seismic performance of such joints. A numerical model for RC joints is introduced and validated. Subsequently, a new seismic retrofit strategy using BRHs is proposed, aimed at relocating plastic hinges and increasing energy dissipation. The results indicate the retrofit method can effectively meet the performance objectives. [ABSTRACT FROM AUTHOR]

This paper first critically reviews a seismological model and then a three-segment curve model (in log-log space) to model the Q-f relationship is proposed to overcome the potential biased estimation in the long-period range by the "coda wave" method. The optimal curve-fitting process is performed to determine the Q-f relationship for the Hong Kong region. The calibrated seismological factors are incorporated with the stochastic simulation procedure to generate synthetic ground motions, which are validated through comparison with seismic records. The impact of long-period ground motions on the seismic response of high-rise buildings is finally manifested through a numerical study. [ABSTRACT FROM AUTHOR]

In this study, industrial single-story RC precast buildings are investigated. Twenty-four case studies have been considered, in which the column height, the beam spans and the seismic hazard level are varied. The seismic design of the selected case studies is performed according to the Italian building code and additional technical documentation. Three-dimensional nonlinear models are defined to perform static and dynamic analyses for the seismic assessment of the selected case studies. Demand/capacity ratios in terms of the selected engineering demand parameters are computed for ten increasing values of the seismic input return period. [ABSTRACT FROM AUTHOR]

The objective of this work is to study the influence of various sources of uncertainties on the seismic response of structural systems. For this purpose, four test examples are considered, in particular two steel and two steel–concrete composite buildings. In order to study the impact of uncertainty on this type of structure, life-cycle cost analysis is performed for each structure, which is a measure of the damage cost due to future earthquakes that will occur during the design life of a structure. The calculation of the life-cycle cost of structural systems requires the calculation of the structural capacity in multiple earthquake hazard levels. Multicomponent incremental dynamic analysis (MIDA) is considered as one of the most efficient procedures for estimating the seismic capacity of 3D structural systems; therefore, in this work, MIDA is incorporated into the seismic loss estimation procedure. In order to take into account uncertainty on the mass, the material properties, the damping and the record-incident angle, the Latin hypercube sampling method is integrated into the MIDA framework. [ABSTRACT FROM PUBLISHER]