Analysis of Construction Risk for Water Piers and Foundations with Double-wall Steel Cofferdam Based on the Fuzzy Fault Tree Theory

Construction risk for water piers and foundations with double-wall steel cofferdam was analyzed by the fuzzy fault tree theory. An evaluation method of construction risk for water piers and foundations with double-wall steel cofferdam was proposed. Fuzzy fault tree of construction risk for water piers and foundations with double-wall steel cofferdam was established based on Yingwuzhou Yangtze River Bridge. 31 bottom events were considered in fuzzy fault tree model according to 2 water pier and foundation with double-wall steel cofferdam. Key process of construction risk was obtained and risk prevention measures were proposed.Results showed that fuzzy number of construction risk probability for water piers and foundations with double-wall steel cofferdam was(0.05015,0.05278,0.05542). Construction risk of 2 water pier was highest. And weld leakage, pile broken and sand boiling were the key processes with higher construction risk. There fore appropriate prevention measures would be taken to reduce the construction risk for water piers and foundations with double-wall steel cofferdam.