A dynamic visual weld shear stress fatigue test device and method

Abstract

The invention provides a dynamic and visualized weld shear stress fatigue test device, which includes a frame, one end of a test piece with a weld is fixed on the frame, and the other end is cantilevered; the cantilever ends of the test piece are respectively equipped with The dynamic system and stress control system that apply the load to the test piece; the mounting frame for installing the power system and the stress control system is installed on the outside of the test piece, and the other ends are respectively connected to the cantilever end of the test piece; an optical fiber detection system is installed on the test piece. There is a visual monitoring system on the outside of the weld of the parts, and the stress application system, stress control system, optical fiber detection system, and visual monitoring system are respectively connected to the PLC integrated system. The present invention also provides a method of using the above device. The device of the invention can make the weld be subjected to pure shear stress, and the PLC integrated system can dynamically observe the dynamic process of the shear stress change of the weld, which is more intuitive and convenient. The method of the invention is simple and refined in operation and meets the requirements of the welding seam shear stress fatigue test.

Description

technical field [0001] The invention relates to a shear stress fatigue test device and method, in particular to a dynamic and visualized weld shear stress fatigue test device and method. Background technique [0002] The structure of the steel bridge deck is complex, and welds are often used to connect the various structures. However, due to welding defects and large welding residual stresses in the welds, fatigue damage and fatigue cracks are prone to occur under repeated loads. Common cracks in the steel bridge deck include welds between the top plate and U-ribs, welds between diaphragms and U-ribs, and butt welds between U-ribs. The stress characteristics of parts prone to fatigue cracks are different. For example, the U-rib butt weld mainly bears tensile stress; stress is more pronounced. [0003] At present, the strength or life research of the above structural details usually uses S-N curves for research, but the fatigue strength curves of normal stress and shear str...

AI Technical Summary

Problems solved by technology

[0004] At present, the fatigue test for the fatigue performance of the steel bridge deck, because the cracking characteristics are difficult to observe, the phenomenon of fatigue cracking may not be found in time, and the cracking process cannot be accurately recorded. Therefore, a test device and test method with full dynamic visualization function are needed

Images