Research On Analytical Method Of Time-dependent Reliability Of Open Type Wharf On Piles

The concrete wharfs in old port are facing serious problem of durability. Open type wharfs on piles are seriously corroded. The piles, pile caps, vertical and horizontal beams and boards splashed by waves are main parts of corrosion. And the wharfs' ultimate bearing capacity has obviously decreased. As time goes by, the structural failure resulted from the problem of durability will become widespread. The accurate evaluation of their reliability is the key to the normal operation of port. At present, the specification still uses the static reliability to evaluate the safety performance of structure. In fact, the reliability changes over time. Hence, we need to establish an effective analytical method of time-dependent reliability. The main content of this article:(1)Chapter one concludes the research progress and problems of calculating method of time-dependent reliability, at home and abroad.(2)Based on the existing research achievement, Chapter two divides the design reference period into several subsections, and establishes an effective analytical method of time-dependent reliability.(3)Chapter three studies the influence factors of ultimate bearing capacity. According to that whether the factor will lead to the decrease of ultimate bearing capacity, the influence factors are divided into two kinds. First kind is‘randomness-influencing factor', and the second kind is ‘attenuation-influencing factor'.The probabilistic models of these factors are established. The probabilistic models ofattenuation-influencing factors are based on the breakage mechanism of durability of the reinforced concrete structure.(4)Based on the probabilistic models of influence factors, Chapter four establishes the probabilistic models of ultimate bearing capacity of wharf's components. With the new calculating method of time-dependent reliability, the time-dependent reliabilities of these components are calculated.(5)Based on the probabilistic models of influence factors, Chapter five uses ANSYS to establish the stochastic process models of ultimate bearing capacity of high-piled wharf. And the integral reliability is calculated.(6)For an engineering example, Chapter six uses the new analytical method of time-dependent reliability, established probabilistic models ofultimate bearing capacity of components and stochastic process models ofultimate bearing capacity of high-piled wharf to calculate the components' reliability and integral reliability of the engineering example.