In this paper,the fracture toughness of Q345 steel was measured by J integral,and then,the failure assessment curves of Q345 steel were determined using option-3 curve and option-1 curve in CEGB-R6 standard.

• 应用J积分法测定了Q345的断裂韧性,并采用R6方法中的选择3曲线和通用曲线绘制了其失效评定曲线。