Numerical Analysis Of Broken Wire In PCCP And Feasibility Study Of Fiber Reinforced Pipe

Prestressed concrete cylinder pipe(PCCP)is widely used in various water conveyance projects for its excellent performance.In recent years,many detonating accidents have occurred for the broken wires in PCCP around world,which have a great influence on the operation of the project and the people's life.Wire breaking is the main reason for pipe bursting.It is also a safety problem prone to happen during pipeline operation.Its influence on pipeline structure performance is the trend of current research.The study on the influence of broken wire was taken combining with the research status at home and abroad,it is the first time to put forward the solution and feasibility study of using corrosion resistant fiber reinforcement instead of steel wire to make fiber reinforced pipe.The main work is as follows:(1)The development process of PCCP at home and abroad was reviewed,the current status of pipeline numerical research was introduced,the trend of numerical research and the shortcomings in modeling were summarized.The method and process of calculating the external load and stress of the pipe are introduced.(2)The finite element software ABAQUS is used to establish the three-dimensional solid finite element model considering the impact of the pipe socket and reflecting the spiral winding of the PCCP steel wire.According to the number of broken wires,1 broken wires,5 broken wires,10 broken wires,15 broken wire and 21 wire breaking pipeline response to load simulation were taken;the different position of broken wire occurred in response to load simulation of pipe were taken.The influence of 1 steel wire breakage,multiple steel wire breakage and steel wire breakage on the stress state of pipeline during operation is obtained by analyzing the simulation results.(3)A new pipe material replacing steel wire is proposed in order to solve the problem of corrosion and fracture of steel wire.The feasibility of prestressing fiber tendons is explored through field wrapping test.Experiments show that fiber reinforced bars can replace prestressed steel wires,but the winding equipment and technology need further improvement.(4)The three-dimensional finite element model of the fiber reinforced pipe is established,and the stress state change of the fiber reinforced polymer pipeline from manufacturing,construction to water running is studied.Compared with PCCP,the performance of fiber reinforced bar is better than that of PCCP.When the same internal pressure is changed,fiber reinforced pipes have better durability.