平面杆件系统如框架,排架,连续梁等作为建筑物的承重结构而被广泛应用。前人对此进行大量研究,如力法,位移法等,近十年来,由于电子计算机广泛地应用,在结构分析中迅速发展一种有效的数值计算方法——有限单元法。在杆件分析中亦称之为刚度矩阵法。有限单元法是近十多年迅速发展起来并获以广泛应用的一种数值计算方法。它起源于结 Planar rod system such as frame, rack, continuous beam as the load-bearing structure of the building has been widely used. In the past ten years, due to the extensive application of electronic computers, an effective numerical calculation method - finite element method has been rapidly developed in structural analysis. In the rod analysis is also called the stiffness matrix method. The finite element method is a numerical method developed rapidly and widely used in recent ten years. It originated in the knot