LIFE PREDICTION OF HIGH TEMPERATURE STRUCTURAL COMPONENT BY STRAIN RANGE PARTITIONING

The s recent works on the improvement of the Strain Range Partitioning(SRP) method and its application to the life prediction of high temperature structural components are summarized. Examined components are divided into three groups, that is, components in the steel production plants, in the automobile and in the fossil power plants. Based on the results of the inelastic analysis and the creepfatigue properties of the material, which were obtained by IJ(=PP,PC, CP, CC) tests, the effects of the material properties, operating conditions and configuration of components were quantitatively evaluated to select the most effective measures for the thermal fatigue life extension. The SRP has been successfully applied until now to the life prediction and extension of the actual structural components subjected to thermal cycling by the s.

Assessment of Aged Offshore Jacket Type Platforms Considering Environmental Loads and Degradation Parameters

Offshore steel structures are a common investment in oil and gas industries operating in shallow to medium depth seas.These structures have become increasingly popular since the mid-19th century,with a typical design life of 30-50 years.Despite their popularity,the structural integrity of existing offshore structures remains a controversial topic.Environmental loads and material degradation have been identified as significant factors that can compromise the structural integrity of offshore structures.To address this issue,this study aims to investigate the reserved strength capacity of a selected offshore structure located in the Malaysian Seas.The study will explore the effect of oceanographic data,variations in vertical load,and corrosion on the structure’s main members.To determine the impact of each variable on the reserved strength ratio(RSR)of the structure,several pushover analyses were conducted with different variables.Previous literature has shown little or no relationship between seawater wave height,gravity loads,and corrosion allowance on submerged steel members and the RSR of offshore structures.However,this study aims tofill this gap in knowledge by examining these variables’effects on the RSR of offshore structures.The study’sfindings indicate that even a slight increase in wave height can significantly impact the structure’s RSR due to the increase in lateral loading,potentially leading to severe damage to structural components and the foundation model.Additionally,gravity loads had an adverse effect on the RSR of the structure when more than double the vertical load was added.Corrosion allowance was also found to impact the RSR,particularly when assuming significant wall thickness corrosion in primary members.Overall,thefindings of this study have important implications for the design and maintenance of offshore structures.The results suggest that engineers and operators should pay close attention to the potential impacts of environmental loads,such as wave height and gravity loads,and material degradation,such as corrosion allowance,on the structural integrity of offshore structures.This information can be used to optimize the design and maintenance of offshore structures,leading to safer and more efficient operations.

在役反应堆压力容器延寿探讨

概述了反应堆压力容器辐照脆化的相关标准,分析了限制反应堆压力容器寿命因素,策划了反应堆压力容器延寿前应完成的辐照脆化研究及技术准备工作,提出了实现在役反应堆压力容器延寿的构想。

人工智能辅助下的海上风力支撑结构延寿评估研究综述

The primary objective of the present literature review is to provide a constructive and systematical discussion based on the relevant development,unsolved issues,gaps,and misconceptions in the literature regarding the fields of study that are building blocks of artificial intelligence-aided life extension assessment for offshore wind turbine support structures.The present review aims to set up the needed guidelines to develop a multi-disciplinary framework for life extension management and certification of the support structures for offshore wind turbines using artificial intelligence.The main focus of the literature review centres around the intelligent risk-based life extension management of offshore wind turbine support structures.In this regard,big data analytics,advanced signal processing techniques,supervised and unsupervised machine learning methods are discussed within the structural health monitoring and condition-based maintenance planning,the development of digital twins.Furthermore,the present review discusses the critical failure mechanisms affecting the structural condition,such as high-cycle fatigue,low-cycle fatigue,fracture,ultimate strength,and corrosion,considering deterministic and probabilistic approaches.

空气钻井钻柱疲劳寿命预测研究

在空气钻井工况下钻柱受力情况非常复杂,受到地层岩性与井身结构变化的影响,钻柱在井下既自转又反转,而空气锤的冲击作用使得钻柱产生周期性的上下纵向振动,在复合载荷作用下常造成钻柱疲劳损伤。为此,本文修正了泥浆钻井工况下钻柱疲劳寿命计算公式,并运用材料力学强度理论计算出了裂纹处的平均应力,提出了计算空气钻井工况下的疲劳寿命计算模型——Walker模型。并结合该模型的计算结果,解释了克拉美丽火山岩气藏空气钻井钻具大量刺穿失效的原因。