WIT Press


Probabilistic And Fuzzy Fault-tree Analyses For Modelling Cave-in Accidents

Price

Free (open access)

Paper DOI

10.2495/SAFE110241

Volume

117

Pages

10

Page Range

267 - 276

Published

2011

Size

725 kb

Author(s)

H. M. Al-Humaidi

Abstract

Construction injury accidents result from different causes. Risk evaluation for cave-ins using traditional fault-tree analysis can be difficult, especially since the variables resulting in cave-ins are unique; in addition, historical data, when available, is often incomplete. In construction, assessment of risk is based on linguistic terms using subjective judgment of linguistic values such as severe, very likely, etc. Such linguistic terms are best modeled using fuzzy set theory. The traditional FTA method has been widely used to calculate the probability of the top undesired event, which is based on historical data of the occurrence and the severity of the basic events. FTA implementation into construction projects needs to be modified since assessment of contributing events to cave-in accidents is based on managerial experience using experiential subjective expressions. This paper introduces a fuzzy triangular model to assess risks associated with excavation work in advance and helps management prepare solutions in advance. Keywords: Fuzzy Logic, fuzzy set, probabilistic fault-tree analysis, fuzzy faulttree analysis, cave-in accidents, construction safety. 1 Introduction Cave-in is the collapse of unsupported trench or tunnel soil edges that take place during excavation. Cave-in accidents result from numerous causes, including management and worker actions, support-system materials, equipment control, weather and natural disasters. These antecedents are categorized into procedural, triggering and enabling causes. Procedural causes are indirect; they impact the frequency of cave-in occurrences because they result in enabling or triggering causes separately or together. Procedural causes arise from management and control issues. Examples of management-related procedural causes are poor

Keywords

Fuzzy Logic, fuzzy set, probabilistic fault-tree analysis, fuzzy faulttree analysis, cave-in accidents, construction safety