Effective Incremental Ground Velocity for Estimating the Peak Sliding Displacement of Rigid Structures to Pulse-Like Earthquake Ground Motions

Predicting earthquake-induced sliding displacements using effective incremental ground velocity

“…In analyses with added restoring stiffness, the FlatSliderBearing element is replaced by the SingleFPBearingElement, which is assigned a radius of curvature of the concave sliding surface. The same model was used in Jampole et al (2018b), which showed that closed-form solutions of a sliding system subjected to pulses were the same as the OpenSees solution.…”

“…If the majority of sliding resulting from a pulse occurs during that pulse, it is justified to derive intensity measures from a single pulse, without accounting for interaction between pulses, to predict peak sliding displacement. Note that the pulse duration does not have an impact on the ratio of sliding before or after the pulse, as can be seen from the closed-form solution for sliding response of blocks subjected to half-sine pulses or triangular pulses (Jampole et al, 2018b).…”

“…To determine the sliding excursion caused by a single pulse, one must further investigate the parameters that cause sliding. A closed-form solution for the response of a sliding block with coefficient of friction = μ between the block and ground has helped to predict the peak sliding displacement of a block subjected to a half-sine pulse (Jampole et al, 2018b). A closed-form solution was derived in terms of the pulse parameters a p (pulse peak acceleration) and T p (pulse duration), and the system strength parameter (friction) μ .…”

“…Based on the closed-form solution, a p , T p , and μ are the key parameters that enable prediction of peak sliding displacement. Jampole et al (2018b) shows that what really matters in predicting peak displacements for blocks subjected to pulses is the incremental ground velocity after the block has started sliding, which is also a function of T p . A parameter, termed EIGV and symbolized by η , characterizes the incremental ground velocity available to produce sliding displacements, as shown in equation 1.…”

“…Furthermore, identification of ground motion intensity measures that correlate well with peak structural response can be of great benefit in selecting earthquake ground motions to be used in response history analyses and in reducing the number of ground motions required to obtain an adequate probabilistic description of the response of the structure. Jampole developed a pulse intensity measure called the effective incremental ground velocity ( EIGV , symbolized η ) to predict the peak response of a rigid sliding block subjected to base shaking from a half-sine pulse (Jampole et al, 2018b). EIGV is a function of the pulse duration, peak pulse acceleration, and the coefficient of friction between the ground and the sliding block.…”