Seismic Reliability Analysis And Optimization Of Truss-type River-crossing Pipe Rack

Pipeline Crossing Projects play an important component of Pipeline Construction, most large projects are generally set in rivers, valleys, or where the geological condition is complex. There are a lot of forms of crossing pipeline structures, Truss crossing pipeline is one of the simplest form. Structure optimization and reliability analysis of truss river-crossing related to the overall performance of pipeline structures. And it plays an important part in structure's safe operation.Uncertainty is widespread in engineering, how to reasonably considering and dealing with these uncertainties and ultimately making a rational decision can not be avoided in engineering design. So, Reliability concepts and theories have emerged and eventually applied in the structural design. There are many ways to calculate Reliability. Due to the improvement of computer performance, many restrictions in reliability calculation have been broken. The theory of reliability Calculation which based on finite element software (ANSYS) is the mainstream method of calculating reliability. Using Monte Carlo - Finite Element Method in reliability Analysis of Truss Structure can both ensure the validity of the results, and also avoid the other method restrictions in mathematical calculating.The goal the structural optimization design is to find the best design in a number of sequences. And ensure the structure's geometry, strength, stiffness, stability and self-vibration frequency can meeting the specification. By changing the structure's geometry, material type, etc which called design variables, the various functions of the structure and the cost of the project could achieve the desired goal. When doing structural optimization calculations, first-order method is more commonly used, because of it is more sensitive to design variables and Converge faster. The results would be more accurate.In this paper we take an actual project as example, did some research on the structure's seismic reliability analysis and optimization Design. By simulating the structure's earthquake response, a simple seismic performance analysis is conducted. Through the reliability analysis, the structure of anti-seismic reliability is got. We focus on the inverted triangle truss structure in practical engineering, while a rectangular truss structure is designed as a comparison. Both of these two kinds are all analyzed. Comparing with the two different solutions of the structures, the most optimal solution can be determined. Structural seismic reliability analysis and optimization provide a useful basis and a good guide for designing.Structure deigned with optimization and reliability Calculation, can not only save material costs and meet the practical engineering needs, but also conducive to on-site construction. Truss structure optimization and reliability analysis can be used not only in the pipe rack design; in other industrial and civil steel constructions also has a wide range of applications.