Opportunity Efficiency - Use Uncertainty Analysis to Evaluate Risks in Construction

In central Taiwan, around the Taichung basin, the ground condition is boulders with red soils and high ground water level. Local technicians have developed an unusual soil excavation method to build the so-called “soil retaining columns”. It is cheap, practical and highly efficient. However it is fraught with risk and uncertainty. In general, use of the injury severity method in occupational injury evaluation is a good solution. But, the method seems unsuitable for high risk situation in construction sites. Traditionally, there are 3 excavation methods to frame the soil retaining piles. Their risk distributions are not similar. Thus, we can’t use the same safety investment budget when we choose different excavation method. In this study, for increase the exactness of “risk quantity”, we focus on the different “risk distribution”. Based our risk evaluation of the “hazard uncertainty” concept and introducing the notion of “opportunity efficiency” to modify usage of the “risk severity” analysis; this concept will increase the accuracy of safety investment evaluations