Basic Study on Overflow Phenomena via Underground Drainage Channels and Pits caused by Tsunami

Abstract

This paper studies about flood disasters via drainage channels caused by tsunami, which may occur even if high seawalls protect coastal land area from tsunami. The flood could make loss of evacuation routes and be an obstacle to the safety measures, thus considering the countermeasures is important for industrial facilities from the points of view of business continuity and recovery actions. Hydraulic physical model tests were conducted to clarify the relation between surging phenomena of pits and overflow from pits, then a few numerical simulation methods were applied to estimate the surging and overflow. It is found that 1-D pipe flow model, which is generally used for a surging analysis, was hard to reproduce the model test results of overflow. Therefore a new improved 1-D pipe flow model was developed and verified.