板桁组合结构分析中的板梁单元

Plate-beam element in calculating plate-truss composite structure

为了能合理和方便地分析板桁组合结构的受力性能,将纵、横梁视为混凝土板的加劲梁,建立考虑板梁共同作用和相对滑移板梁单元、无共同作用和过渡区的板梁单元。其中,将矩形板视为单元的基本部分,梁视为附属部分,即以矩形板4个结点的结点位移以及每条板梁结合面(有钉区)中线上的3个相对滑移自由度作为板梁单元的基本自由度,以构造板和梁的位移模式,由此得到板梁单元的单元刚度矩阵。

For analyzing the properties of plate-truss composite structures expediently, the platebeam elements were set up in which the action and slip between the plates and beams were considered. Composite elements in which plates have no action to beams and excessive elements were also established. In these elements, plates were the basic parts, and beams were the adjunctive part. That is to say, the displacement pattern of plates and beams was constructed with the basic free degrees of the displacement of 4 nodes on rectangular plate and the relative slips of 3 nodes at combining surface between beams and plates. Thereby, stiffness matrixes of plate-beam elements were obtained.