Research on Ultrasonic Flaw Detection of Steel Weld in Spatial Grid Structure

2nd International Conference on Civil Engineering and Materials Science

Du, Tao^1 ; Sun, Jiandong^1 ; Fu, Shengguang^2 ; Zhang, Changquan^3 ; Gao, Qing^4

Shandong Academy of Building Research, Institute of Structure, Jinan

250031, China^1

Feicheng Construction Engineering Quality Supervision Station tai'An, 271000, China^2

Shandong Provincial Department of Housing and Urban Rural Development, Jinan

250000, China^3

Shandong Hi-speed Company Limited, Jinan

250000, China^4

关键词: Construction quality;    Conventional detection;    Detecting conditions;    Non-destructive test;    Spatial grid structures;    Statically determinate;    Ultrasonic detection;    Ultrasonic flaw detection;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/216/1/012016/pdf
DOI  :  10.1088/1757-899X/216/1/012016

来源: IOP

【 摘 要 】

The welding quality of spatial grid member is an important link in quality control of steel structure. The paper analyzed the reasons that the welding seam of small-bore pipe with thin wall grid structure is difficult to be detected by ultrasonic wave from the theoretical and practical aspects. A series of feasible detection methods was also proposed by improving probe and operation approaches in this paper, and the detection methods were verified by project cases. Over the years, the spatial grid structure is widely used the engineering by virtue of its several outstanding characteristics such as reasonable structure type, standard member, excellent space integrity and quick installation. The wide application of spatial grid structure brings higher requirements on nondestructive test of grid structure. The implementation of new Code for Construction Quality Acceptance of Steel Structure Work GB50205-2001 strengthens the site inspection of steel structure, especially the site inspection of ultrasonic flaw detection in steel weld. The detection for spatial grid member structured by small-bore and thin-walled pipes is difficult due to the irregular influence of sound pressure in near-field region of sound field, sound beam diffusion generated by small bore pipe and reduction of sensitivity. Therefore, it is quite significant to select correct detecting conditions. The spatial grid structure of welding ball and bolt ball is statically determinate structure with high-order axial force which is connected by member bars and joints. It is welded by shrouding or conehead of member bars and of member bar and bolt-node sphere. It is obvious that to ensure the quality of these welding positions is critical to the quality of overall grid structure. However, the complexity of weld structure and limitation of ultrasonic detection method cause many difficulties in detection. No satisfactory results will be obtained by the conventional detection technology, so some special approaches must be used.