持续损伤中能量的传递和遗失对焊接钢桥结构影响

焊接钢桥结构持续损伤至破坏的过程可以从两方面加以分析:一方面要考虑此过程中能量的耗散;另一方面要考虑此过程中焊接部位损伤负向激励。基于Griffth能量准则思想,提出了结合动态能量相互传递与遗失理论(TETL)和损伤负向激励机制(MDPE)并考虑焊接钢桥结构剩余寿命的综合评估方法。将提出的综合评估标准应用到钢桥结构中,耦合了损伤负向激励机制与焊接结构参数之间的关系。从而有机地促进了能量相互传递与遗失理论和损伤负向激励两个方向的整体结合。为验证方法的有效性,给出悬臂梁和X形框墩二者的焊接连接的数值算例,并与基于S-N曲线的CD法和检测评估方法进行了分析比较,为钢桥结构安全寿命提供了一种较为实用的预测途径。

EFFECT OF ENERGY TRANSMISSION AND LOSING ON WELDED STEEL BRIDGE UNDER CONTINUOUS DAMAGE

For the behavior of structure fracture,the dissipation of energy and the damage of passive encourage should be taken into consideration in the course of dynamic damage.This paper presents a comprehensive assessment method which combines the theory of energy transmission and losing(TETL)and the mechanism.The comprehensive assessment standard has been applied to the case of steel bridge,which defines the relation between the mechanism of the damage of passive encourage and welded structure parameters.These tremendously improve the combination of TETL and MDPE.The results are compared with the method of CD and target reliability,numerical simulation about steel bridge demonstrates that the method this paper presented is reasonable and effective.There are certain application prospects in the security design of the steel bridge.