A brief study on the integral combined local optimisation design of trusses based on structural mechanics solver modelling

With the rapid development of social construction, various structural types and demands are increasing, and truss structure is thus born. People not only pursue safety and stability, but also pay more and more attention to economic efficiency and endeavour to reduce material usage. Therefore, the optimisation of truss design has become an important trend. In this paper, with the help of structural mechanics solver, a truss design is carried out for a real engineering condition and a simple design optimisation is made. The project is analysed and researched according to the three steps of design-calculation-optimisation. With the help of the axial force and bending moment of each member output from the structural mechanics solver, the material dosage is calculated, and the design scheme is constantly improved, from which a brief optimisation method is sought to find a practical and feasible method. The design scheme is divided into the under-bearing type and the combined type, and the optimisation of the two is carried out, and the optimal design scheme is further proposed, and finally a comprehensive comparison is made. It is found through example calculations that material usage can be reduced by reducing spans, using short bars and adopting parallel truss design while ensuring the safety and stability of truss bridges. Especially when designing multi-span truss bridges, the overall material usage is reduced by increasing the use of short members, although the overall number of members will be increased.