关键词: 大跨度钢结构, 施工模拟, 分步施工, 生死单元法, 边界转角, 独立求解

Abstract:

One of the difficulties in mechanical analysis of construction process is the time variable of structure geo-metry and boundary conditions.In this investigation,first,based on the engineering practice that a pre-angle can be set between pre-erected and after-erected substructures via an inter-node design,a new construction simulation method is proposed.In this method,live and dead substructures are solved sequentially,and the rotational constraint on boundary nodes of dead substructures can be adjusted.Then,for the system with statically-determined or super-determined dead substructures,two methods to adjust the boundary rotational condition are presented,and the finite element formulas of live and dead substructures are respectively derived.Finally,the proposed method is used to analyze and simulate some typical cases.The results indicate that,by using the proposed method,the after-erected substructures deform more slightily and can be facilitated more easily.As a result,the final geometry is closer to the design shape.

Key words: long-span steel structure, construction simulation, step-by-step construction, birth-death element method, boundary rotation angle, individual solving