中文摘要：

对服役中的海洋井架结构进行检测评估，保证其服役期间的安全性和适用性具有重要意义。通过现场检测获得某海洋钻机井架结构当前状态的服役数据，采用ANSYS软件建立了其结构分析模型，并基于模型修正理论进行修正，获得符合井架实际状态的精准模型，进而从结构强度、动态响应、稳定性以及可靠性4个方面系统地对结构进行了安全评估。评估结果表明，该井架综合性能良好，整体可靠性指标为7．15，检测发现的腐蚀、整体弯曲及构件弯曲对井架212作性能和承载能力影响较小，井架可继续安全服役。为防止井架结构进一步腐蚀恶化，需对井架腐蚀构件喷涂防腐层，以保证其后期服役的安全性。

英文摘要：

The inspection and evaluation of in-service offshore drilling derrick structure have a significant ira- portance on the safety and suitability of the derrick during service period. Based on the current structure data of an offshore derrick acquired by field detection, a structural analysis model is established by using ANSYS software and is modified based on model correction theory to obtain an accurate model of the actual state of the derrick. Then, a systematic safety assessment of the derrick structure has been conducted including the structural strength, dynamic response, stability and reliability of the derrick structure. Assessment results show that the derrick had a good over- all performance with an overall reliability index of 7.15. The detected corrosion, structure bending and part ben- ding had little effects on the derrick operating performance and load carrying capacity, thus, the derrick could continue to operate without safety concern. In order to prevent further corrosion of derrick structure and ensure the safety in the latter operation, spraying erosion resistant coating on corrosive components of derrick is required.