基于ALGOR的近海平台延寿静力评估

Static Analysis of Offshore Platform Life Expansion based on ALGOR

基于检测得到的腐蚀减薄、桩基冲刷、海生物附着等服役损伤，建立海洋延寿平台结构有限元模型。依据平台工程地质勘察资料，建立桩-土作用非线性系统模型，采用ALGOR软件进行平台静力评估。分析可能同时作用于平台的各种载荷，按平台结构受力最不利的情况进行组合，得到34种基本工况，65种组合工况，共计99种计算工况。依据静力评估结果，采用浅海固定平台规范进行平台结构强度校核。校核结果表明：平台最初设计较为保守，到达设计寿命后仍满足延寿5年的要求，平台极限冰载荷工况为最不利工况，此时构件最大U．C．为0．95，严重冰情时需要加强平台监控。

Based on service damages such as corrosion caused reduction, scouring around pile foundation and adhesion of living beings, a finite element model of the structure for life-expanded offshore platform is established in this paper. Based on the data from geological investigation of platform engineering, a nonlinear model of file-soil impact system is established, and static analysis of offshore platform is conducted by adopting ALGOR software. Various loads which may impact offshore platforms at the same time are analyzed. Concerning the most unfavorable loading situation on offshore platform structure, 34 kinds of basic working conditions and 65 kinds of combined working conditions can be obtained, and totally 99 kinds of working conditions is considered. Based on the results of static analysis, platform structural strength check is conducted by adopting the criterion of the fixed platform in shallow sea. The results of checking indicate that if the initial design of the platform is more conservative, the requirement of expanding life for 5 years can still be met after the designed life is reached. When the ultimate ice load occurs, which is the most unfavorable working condition, the maximum value of the constructional element U.C. is 0.95. When ice situation is severe, the supervision to the platform is needed to be enhanced.