An evaluation of the outcomes probabilities of roadway bridge defect model using Event Tree method

摘要

Event tree method is among of the risk assessment tool that is widely used to evaluate the probability of failure and its consequences of a system. This paper presents the use of Event Tree method in modelling the outcomes of bridge defect in terms of possible events which contribute to the failure. The evaluation model of outcomes using Event Tree method was presented in terms of five levels of outcomes of the bridge defect. The level are divided into categories of disastrous, severe, medium, minor and good with a range value of probability in between 4 × 10~(-6) to 0.59. These probabilities were obtained by considering a range value of minimum, medium and maximum probability of the initiating event of Fault Tree analysis. The range probability values of Event Tree result will categorized the outcomes of bridge defect into five levels for the decision making process of the bridge failure mitigation action. These results of failure and consequences also may provide guidance for future safety management for bridge structure especially in the development of risk matrix.