Risk Assessment in Bridge Construction Projects Using Fault Tree and Event Tree Analysis Methods Based on Fuzzy Logic

Abstract

In this paper, interruption risk in construction activities of bridge projects is assessed in order to identify the main causes of its occurrence and also to determine the potential outcomes resulted from the risk occurrence. To do this, fault tree and event tree analysis (ETA) methods are applied. As the application of the traditional approach of these two methods is difficult in many cases due to limited access to information, fuzzy arithmetic can be considered as a useful tool. In this research, first, fault tree structure is created according to consequences resulted from the Delphi method. Then, the probability of risk occurrence is calculated by applying fault tree analysis (FTA) based on fuzzy logic. By establishing the structure of fault tree related to the failure risk of mitigation strategies, the main causes relating to failure of strategies are identified. The structure of the event tree is created using the obtained results; moreover, the expected monetary value (EMV) of risk event is computed. Finally, to validate the results obtained, a model is created by Monte Carlo simulation and then the results obtained by applying the two methods are compared. The EMV of the risk event evaluated in this paper is determined to be 9.93% of the project baseline cost.

A new risk assessment method based on belief rule base and fault tree analysis

“…Therefore, reasonable belief rules are established by FTA from the mechanism analysis of the logical relationship between risks, which makes up for the shortcomings of the existing BRB-based risk assessment model. The indicator set of FTA-based risk assessment is shown in equation (6).…”

“…It is widely used to identify the risk of devices used in nuclear power plants, building, electricity, 1 aviation, internet technology (IT), 2 transport, 3 finance, the environment, and industry. [4][5][6] In the risk assessment of the optimal maintenance of complex industrial systems, various methods have been applied. For instance, (1) Quantitative risk assessment: In the external flood risk assessment of nuclear power plants, Bani-Mustafa et al 7 adopted an extended method of hypothesis bias assessment in quantitative risk assessment; Combined with the conventional data and the data of the applicant's dynamic transaction behavior, a credit risk assessment method based on radial basis function (RBF) and multi-instance learning (MIL) is proposed 8 ; Zhang et al 9 established the risk matrix by using risk frequency and consequence to evaluate the safety risk of oil and gas industry.…”

An Approach for Risk Prioritization in Construction Projects Using Analytic Network Process and Decision Making Trial and Evaluation Laboratory

“…A real case study is investigated to indicate the performance and efficiency of proposed method. Abdollahzadeh and Rastgoo [25] used FTA and ETA to assess the main causes of interruption risk in construction activities of bridge projects. Furthermore, the probability of risk occurrence is calculated by applying FTA based on fuzzy logic.…”

Risk Analysis of Earth-Rock Dam Failures Based on Fuzzy Event Tree Method

“…The application of the ETA method based on fuzzy set theory in dam failure risk analysis of an earth-rock dam can be summed up in the following steps [ 32 ]: In view of the probable dam-breaking event, analyze the various accident paths and the accident links of the dam and establish the event tree structure chart. Calculate the probability of dam failure for all dam-breaking paths under each load condition.…”