海洋结构断裂强度特性评估方法综述

Safety Assessment Procedure For Offshore Structures Based Upon Their Fracturing Characteristics

在设计用于冰海等恶劣的自然环境下的海洋结构物时，海洋结构适应低温脆性断裂的安全性将是一项极为重要的研究内容。本文将着重介绍目前国外在海洋结构的基础设计阶段中，运用断裂力学，掌握疲劳裂变的发展和脆性断裂出现时的构件断裂强度特性的方法。同时还将介绍以此为基础，开发出的海洋结构安全性评估方法。一般我们在通过小型模型试验和ＦＥＭ解析海洋结构时，常会产生仅通过这些是否就能达到高精度地、极其方便地估算出节点结构极为复杂的海洋结构断裂强度特性的疑点。为此，这里将通过对国外以半潜式海洋结构节点密布区域为对象的、以实物尺度结构模型试验，来对其进行研究、分析的动态。及其由此而获得的即使在这类结构的基本设计阶段，也能适用的以断裂力学为理论基础的安全性评估方法。

One of the important design procedures for subarctic offshore structurea is for safety assessment against low temperature brittle fracture threatening to occur in their steel members.In this paper we discuss the safety assessment procedure based upon the knowledge about the fracturing characteristics of such offshore structures,which can be estimated from such phenomena as fatigue crack propagation and brittle fracture initiation,as obtained by employing fracture mechanics at the basic design stage.Our conclusion is that the safety assessment procedure dependence on fracture mechanics could be a very useful tool for designing such offshore structures even at the initial design stage.