Seismic response and design of buried concrete pipes subjected to soil loads: Fid-Bau Portal

Seismic response and design of buried concrete pipes subjected to soil loads

Alzabeebee, Saif

Highlights • The seismic response of buried concrete pipes have been studied. • The effect of the seismic response on the bedding factors have been carefully investigated. • The accuracy of the AASHTO bedding factors have been examined. • New equations have been proposed to estimate seismic bedding factors.

Abstract Concrete pipes are a crucial element in sustaining contemporary life because they afford appropriate means to transport drinking water, sewage, and storm water. Thus, these useful assets must be designed correctly. The current methodology to design these assets is based on factors called the bedding factors; these factors have been developed considering only static loads. Evidences from previous studies showed that buried structures, including concrete pipes, are vulnerable to failure due to seismic shake. However, no study has been found in the literature to address the response and the design of buried concrete pipes subjected to seismic shake. Thus, this research aims to study the seismic response and seismic design of underground concrete pipe subjected to soil loads. The combined influence of the seismic shake and diameter of pipe, burial depth, installation condition, and intensity of the seismic shake have been studied using a carefully developed finite element model. The results showed that the seismic shake noticeably rises the maximum bending moment; however, the percentage increase remarkably influenced by the diameter of the pipe and the burial depth. Furthermore, the percentage rise of the maximum bending moment declines as the installation quality becomes poorer. The results also showed that the maximum bending moment rises nonlinearly as the acceleration rises. Comparisons with the current AASHTO bedding factors illustrated that these factors either conservative or unsafe. The reasons for these inaccuracies in the current design bedding factors have been discussed and novel equations to predict bedding factors that consider the seismic shake have been derived using novel intelligent data mining technique. The accuracy of the proposed equations has been demonstrated and thus, these equations can be used by practitioners/designers to implicate the effect of seismic shake in the design of buried concrete pipes.