Risk Analysis On The Stability Of Large-Diameter Concrete-Filled Steel Pipe Pile In Deep Water During Construction Period

With the development of shipping industry, more and more deep water berths will be required, so the requirement for wharf piles will be more and more strict; the bridges which cross over the big rivers even cross over seas also put forward a new challenge to deep water pile foundations which have a significant impact on the whole project. Therefore, how to reduce the construction risk of deep water piles has been paid close attention gradually. The research work concludes three parts in general:Firstly, all kinds of deep water piles accidents during construction and their possible causes were obtained according to the collected accidents cases; then fault tree of concrete-filled steel pipe pile during construction was established on the basis of the statistical data, and fault tree analysis was carried out.The second part is the pile reliability analysis. Based on literature research, the method which integrates Monte Carlo simulation technique and finite element method was used to quantify the reliability of concrete-filled steel pipe pile during construction considering pile-soil interaction behavior and uncertainties in various variables. Uncertainties associated with horizontal foundation coefficients, rock-socketed length, section properties of the pile and load conditions were explicitly considered.Finally, according to contract cost of practical project, the construction cost was discussed in detail considering different construction phases, different geological conditions and different length of piles; combined with the results of the cost analysis and reliability analysis, fuzzy theory was used to calculate the direct economic loss of pile during construction.