Seismic interaction of underground RC ducts and neighboring bridge piers in liquefiable soil foundation

Abstract

A coupled system of an underground reinforced concrete (RC) duct and a neighboring bridge pier supported by group piles is numerically investigated in sandy soil at both drained and undrained liquefiable states under seismic ground excitations. Parametric studies are conducted to evaluate influencing factors on seismic performances of these neighboring interactive structural systems. The numerical simulations are performed with the finite element code COM3 (COncrete Model for 3D) (Maekawa, Pimanmas and Okamura in Nonlinear mechanics of reinforced concrete, 2003), which is capable of simulation of inelastic performance of RC structure and high nonlinearity of soil medium, especially on the liquefiable loose sand. It is mechanically pointed out that liquefaction-induced uplift of underground ducts is substantially influenced by the presence of on-ground bridges. Alternatively, inertial forces induced to the onground bridge pier are also noticeably affected by the presence of the neighboring underground RC duct. It is pointed in practice of design that these nonlinear interacting responses between these neighboring infrastructures are greatly magnified on liquefiable soil foundations.

Mechanism of Long-Term Excessive Deformation and Delayed Shear Failure of Underground RC Box Culverts

“…Since the out-ofplane shear failure is a problem in danger, the diagonal shear crack propagation, which is possibly associated with drying shrinkage of concrtete, shall be simulated (Gebreyouhannes et al 2014) as well. Furthermore, the nonlinear soil-structure interaction is to be consiered for investigating the mecahnism of damages Moshirabadi et al 2015).…”

Dynamic structure-soil-structure interaction of piled high-rise buildings under earthquake excitations I: Influence on dynamic response

“…The SSSI that occurs in urban areas can be subdivided into the interaction between underground structures (such as tunnels [30] ), between an underground structure and a surface structure (such as between a subway station and highrise building [31][32][33] or between a tunnel and frame [34][35][36] ), between surface structures [37][38][39][40] , and between structures of other types (such as between liquid-storage tanks [41] , or between a duct and bridge pier [42] ). In addition to these interactions among a small number of structures, some researchers have proceeded one step further to analyze the influence of large groups of buildings and site effects due to the subsoil configuration on the seismic response of the overall system by theoretical, numerical and experimental methods [43][44][45][46] .…”