Dynamic Responses of Pipeline Suspension Bridges

Abstract

The objective of this engineering study is to determine the dynamic responses of pipeline suspension bridges. To this end, four existing pipeline suspension bridges are analyzed: the 259.2‐m Patterson Loop Aerial Crossing (PLAC) and the 307.2‐m Avalon Extension Aerial Crossing (AEAC), both of which span the Wax Lake Outlet near Patterson, Louisiana, the 457.2‐m Missouri River Pipeline Bridge (MORB) in Plattsmouth, Nebraska, and the 655.3‐m Mississippi River Pipeline Bridge (MIRB) in Grand Tower, Illinois. Modal and response spectrum seismic analyses are performed on finite element models of these bridges. The results indicate that the MORB and the MIRB could experience high levels of stress approaching the yield stress at the end connections of the suspended pipes under earthquake excitations with maximum ground accelerations of 0.50g. These high levels of seismic intensity could also cause distress in the support towers of the PLAC and the AEAC.