组合梁考虑界面滑移弹性单元刚度矩阵计算

s the existence of interfacial slip of the steel-concrete composite beams (hereinafter referred to as composite beams)and the calculations of its deflection impacted by the geometry and load form, restraints form, which make the use of analytical method for solving difficult, while the use of the finite element method in calculation is relatively simple and unified. However, the key to the finite element method is the calculation of element stiffness matrix, and there so many ways to calculate the element stiffness matrix. This paper uses three different common methods to calculate the element stiffness matrix, namely the total potential energy method, principle of virtual work method, the direct stiffness method, and analyzes the difference of the element stiffness matrix which obtained by these three methods. The accuracy of results use the analytical method to confirm.