Finite Element Analysis And Optimization Design Of Glass Fiber Reinforced Plastics Mortar Pipes

Glass fiber reinforced plastics mortar pipe(FRPM), with many excellent physical and chemical properties, is a new type of plastic-matrix composite pipe. The FRPM is consist of unsaturated polyester resins as the base, glass fibers as the enhanced body and quartz sands as the insert material. The special sandwich structure provide the FRPM with low cost and high strength and stiffness. Based on excellent mechanical properties, the FRPM is widely used in the drainage system of municipal water supply.Up to now, researching on the FRPM is only about experimental studies. Research for mechanical properties of the pipe have not been reported in literatures. Based on the composite material laminated plate theory(CLPT), mechanical tests and numerical simulations for the FRPM are discussed. The main contents and achievements in this paper are list as follows:(1) Theoretical research on mechanical properties of FRPM are conducted. Based on the previous theories, this paper firstly analyses the failure strength riles and the stress-strain relationship of composites. Aiming at the special sandwich structure, traditional CLPT is modified and extended to FRPM.(2) Tensile test and ring stiffness test are designed. The axial tensile strength and the radius compressive strength are determined. Based on Tsai-Wu polynomial criterion, Mechanical properties parameters of FRPM by finite element simulation are analyzed. The numerical simulation results agree well with experimental ones.(3) The method of parametric unitary optimization of FRPM is presented in this dissertation. Influences of different design variables on strength of FRPM are analyzed. Based upon the strength analysis, the optimum structure of FRPM is determined.