一、基本公式及计算方法 (一)基本公式 三维有限元的支配方程及应力公式为式中:[K]为整体劲度矩阵;{δ}为结点位移列阵;{R}为等效荷载列阵;{σ}为应力列阵;[D]为弹性矩阵;{ε}为应变列阵;[B]为几何矩阵。 式(3)为沿z轴照射时的应力公式,沿x轴、y轴照射的应力公式与式(3)类似。 First, the basic formula and calculation methods (A) The basic formula Three-dimensional finite element governing equations and stress formula is: where: [K] is the overall stiffness matrix; {δ} is the node displacement array; {R} is equivalent Load array; {σ} is a stress array; [D] is an elastic matrix; {ε} is a strained array; [B] is a geometric matrix. Formula (3) is a stress formula when irradiated along the z-axis, and the stress formulae irradiated along the x-axis and the y-axis are similar to the formula (3).