2.1 一般原则................................................................................................2-1 2.2 一般指导....................................................................................................2-1 2.3 断裂位置...............................................................................................2-2 2.4 断裂严重性...............................................................................................2-2 2.5 断裂阈值标准.......................................................................................2-4 2.6 断裂修复选项.......................................................................................2-4 2.7 作为永久性修复的设计修改....................................................................2-5 3 技术背景.................................................................................................................... 3-1