Effects of spatially variable ground motions on the seismic response of a skewed, multi-span, RC highway bridge

Evaluation of seismic response of bridges under asynchronous excitation and comparisons with Eurocode 8-2 provisions

“…It is seen that the EC8 simplified approach leads again to negligible increase in ρ-ratios, whereas the comprehensive approach shows an unfavourable increase of 30% of the maximum ratio observed among all piers. However, despite the fact that the soil stratification studied was taken to correspond to an extreme case, the results derived using the more refined approach are an indication that for bridges (even short ones) crossing significantly varying soil profiles, the effect of asynchronous excitation is indeed complex and can be proven unfavourable, as also pointed out by other researchers (Lou and Zerva 2005). As a result, from this perspective, the distinction suggested by EC8 between uniform and non-uniform soil profiles, is found to be valid, although, in absolute terms the method fails to quantify the unfavourable role of soil variability.…”

“…The importance of asynchronous excitation has also been studied for skewed bridges (Sextos et al 2004;Lou and Zerva 2005;Burdette and Elnashai 2007). Not surprisingly, these more complicated structures, were shown to be even more sensitive to the assumptions made regarding the spatial variation of earthquake ground motion.…”

Excitación sísmica asíncrona en puentes: patrones de asincronismo, métodos de análisis y tipologías estudiadas

“…By replacing equations 7 and 8 in equation 6, we have: (Lou and Zerva, 2005), specifically in the way of obtaining or generating the seismic records for each support of the structure. (Ramadam and Novak, 1993) (Sgambi, et al, 2014) …”

“…The loss of correlation is the pattern that produces a higher increase in internal forces and displacements according to (Saxena et al, 2000), (Price and Eberhard, 1998), (Lou and Zerva, 2005) and (Burdette and Elnasha,i 2008). However, the authors recommend taking into account the three asynchronous patterns separately and in combination.…”

Anti-symmetric mode excitation and seismic response of base-isolated bridges under asynchronous input motion

“…The impact of multi-support excitation on the seismic behavior of bridges has also been investigated in the frequency (using response spectrum-based methods [1,[37][38][39][40][41][42][43]) and the time domain. In the second case, numerous studies investigated both the linear and/or the non-linear response of different types of bridges, namely: (a) straight bridges on uniform [44][45][46][47] or varying soil profiles, ignoring [45,47,48] or accounting for the soil-structure interaction (SSI) effects [49,50], (b) curved bridges [47,51,52], (c) skewed bridges [45,53], and (d) isolated bridges [54][55][56][57]. An extensive comparative study of 27 different structural bridge systems was presented by Sextos & Kappos [58].…”