Estimation of Link Reliability under Natural Disaster Environment

Abstract

National resilience is an urgent necessity under disaster environment; however, this resilience can be achieved when a highly reliable highway network is built. In this paper, therefore, aiming at highly reliable highway network for long term horizon, a method for estimating the link reliability under disaster environment is proposed. A road network reliability analysis consists of two phases. The first phase is the calculation of node-to-node reliability analysis on the basis of a predefined set of link reliability developed by Wakabayashi and Iida (1992). Meanwhile, the second phase corresponds to the estimation of the link reliability. However, in this methodology, obtaining or estimating a set of link reliability as input data is difficult because few methods have been proposed to collect the necessary data. As a result, few studies were conducted to establish a method to estimate the link reliability. Furthermore, as each event has different characteristics such as earthquake, flood and land slide etc., thus different methods to estimate the link reliability should be required.In this work, first, the problems regarding link reliability estimation are discussed. Afterward, the effects and characteristics of each disaster are categorized and compared. A typical method for slope failure is, thereafter, explained, and a new method for flooding disaster is introduced. Lastly, the difficulty of link reliability estimation considering earthquakes is summarized and discussed, followed by a pilot study in which the Fuzzy set theory is applied.