A Simplified Seismic Design Method of Water Lifelines in Developing Countries

摘要

The water supply system of Yangon, Myanmar, is aging so that almost 50% of the supplied water is lost due to leakage. To upgrade the water system, a retrofitting plan appropriate to a developing country is expected. In this regard, a simplified seismic design guideline for underground structures is proposed. Seismic design formula is prepared not only for continuous pipes, but also for mechanical joint pipes. As current seismic design method for above ground structures is often formulated for three different performance modes (IO, LS, and CP) so the similar design formula should be prepared for underground structures. Failure modes for those three different limit states are defined and their corresponding pipe joint criterion for their performances is formulated in this study. The seismic performance of the pipes can be assessed by the pipe damage mode such the leakage, pull-out, and buckling failures at the joint. The numerical calculation is given to show the seismic assessment of the pipes with current seismically vulnerable joints as well as that of seismically resilient continuous pipes.