近海平台管状接头极限分析的半解析法

本文从极限分析上限定理的一般形式出发，推导出薄壳结构极限分析上限解的非线性规划公式，为克服解析解中机动可能速度场假设的困难和数据解中计算工作量过大的问题，提出了用半解析法进行管状接头的极限分析，即将弦管和支管分别沿环向离散，而轴向则构造分段连续的机动可能速度场，实例计算表明半解析法切实可行，具有计算方便，费用低廉的优点。

A Semi-analytical method for the Limit Analysis of Tubular Joints of Offshore Platforms

The limit analysis of tubular joints can be considered as a nonlinear programming problem. The formulation for the mathematical programming of the upperlimit load is derived, based on the generalized upper limit theorem. The semi-analytical method is adapted for overcoming the difficulty of assumption of kinematically admissible velocity field and for the purpose of reducing computing cost. Then the tube is discretized in the circumferential direction, and the kinematically admissible field is described by sectionally continuous function in the axial direction in the present paper. The numerical examples show the feasibility,economy and convenience of the semi-analytical method for the limit analysis of the tubular Joints.