关键词: 近海平台结构, 贮备强度, 安全裕度, 概率评估方法, 工程优化准则算法, 工程软件

Abstract:

On the basis of probabilistic evaluation theory of ultimate strength analysis,the sophisticated and systematic studies on reserve strength and safety margin of 3D large scaled jacket structure system,under the background of an in-serve off shore platform were made in this paper.Stressed on the platform structure characteristics,this work paid more attention and discussion to pushing-shear effect of tubular joints,local and bulky tubular buckling failure pattern,engineering structure collapse criteria and structural system failure paths searching strategy,etc.An effective engineering optimal criterion for cutting off failure model enumeration was proposed.With load incremental method,a complete probabilistic evaluation procedure of reserve strength and safety margin for the mentioned structural system was constructed and also programmed.A practical engineering example was used to check its reasonableness and feasibility of the above algorithm procedure,and the numerical results in Table 2 were identified in fairly good agreement with some maintenance situations in engineering practice,which shows that the proposed safety evaluation procedure is effctive and reliable.

Key words: offshore platform structure, reserve strength, safety margin, probabilistic evaluation pracedure, engineering optimal criterion, program software