NEAR-FAULT GROUND MOTIONS WITH PROMINENT ACCELERATION PULSES PART II: SHAKING TABLE EVALUATION OF STRUCTURAL RESPONSE AND DAMAGE UNDER ACCELERATION PULSES

This paper is part II to a companion paper on Near -Fault Ground Motions with Prominent Acceleration Pulses, Part I. The experimental study reported in this paper was carried out through an international cooperation research project between the Institute of Engineering Mechanics, China Earthquake Administration (IEM, PRC) and Multidisciplinary Center for Earthquake Engineering Research (MCEER, USA). Based on the evaluation of acceleration pulse characteristics and damaging potential, a series of shaking table tests on three R/C single story structures and one high-rise building structure (54 floors) were carried out under either pulse-dominant full-time-history ground motions or corresponding segregated pulse excitations. Test results showed that the observed values of acceleration, velocity and displacement under segregated pulse excitations were all not less than those under full-time-history ground motions, and the pulse effects were obvious in both elastic and inelastic responses. Damage check and visual inspection of the specimens after each test showed that the segregated major pulses had almost the identical damage potential as the original time-history records. These phenomena verified that the major pulse in pulse -dominant ground motions recorded in Chi -chi earthquake (Taiwan 1999) have the controlling effect for most type of building structures. Moreover, to compare the difference of the story lateral deformation-force relationship of structures under static and earthquake dynamic load, a fourth single story R/C frame structure identical to the above mentioned 3 single story structures was used for the quasi-static test. The results showed that the dynamic lateral resistant capacity of the structures in shaking table tests was about 20% higher than that of the same