Static And Dynamic Analysis And Optimization Research For Design Of Pipeline Suspension Bridge In OIL And GAS Transmission Engineering

In the past10years, with a large number of oil and gas pipeline construction. large engineering across the river becomes more and more. Pipeline suspension bridge was paid great attention for its great spanning capacity. low cost and elegant features etc. The engineering studied in this paper is Nujiang pipeline suspension bridge in China-Burma oil and gas pipeline projects. The process to determine initial configuration and internal force of the finished bridge state was proposed by using the first order optimization of ANSYS. And nonlinear static analysis, dynamic analysis and seismic time-history analysis of pipe-bridge coupling were studied by ANSYS, and comparison analysis were executed by considering the cases by setting different pipeline support constraints, number of steady cable, dip of wind cable, force of wind cable, position of pipeline, mass of oil and gas and the effect of pipe-bridge coupling. Then, according to structural characteristics of the pipeline suspension bridge, the design process was summarized. Design parameters of similar projects were compared with each other and recommendations were made to the existing specifications. Finally, based on these studies, the suggestions of design optimization were proposed. The main conclusions were listed as follows:(1) Nonlinear analysis method should be adopted for analysis of pipeline suspension bridge.(2) Across-wind load and maintenance loads are usually unfavorable load cases in nonlinear static analvsis.(3) With the set of wind cables and steady cables, the frequency of the structure is greatly improved. In addition, reasonable angle and initial tension of the wind cable can make a significant contribution. In seismic time-history analysis, wind cable and steady cable can improve bearing ability of the structure and reduce the structural displacement.(4) In dynamic analysis, the mass of oil and gas and the stiffness of pipeline cannot be neglected, and the pipeline support constraints should be taken into account. The boundary conditions have a significant impact on the seismic time-history analysis of pipe-bridge coupling system. The pile-soil interaction should be precisely considered when there was the great difference in the stiffness of the tower foundation between each side.(5) The damping ratio has a great influence on the structural safety, and the value for analysis should be considered cautiously.(6) The optimal values of the damper have relation to the boundary conditions, pipe-bridge coupling effects should be considered in the parametric sensitivity analysis of dampers.(7) Rational setup of wind cable and reasonable selection of steel crating should be considered in the design and optimization of pipeline suspension bridge.