Experimental study on progressive collapse-resistant behavior of planar trusses. (15th March 2017)

• Record Type: Journal Article
• Authors: Zhao, Xianzhong; Yan, Shen; Chen, Yiyi; Xu, Zhenyu; Lu, Yong
• Is Part Of: Engineering structures. Volume 135(2017:Mar. 15)
• Page Start: 104
• Page End: 116
• Publication Date: 2017-03-15
• Subjects: Planar truss -- Member removal -- Progressive collapse -- Collapse-resisting mechanism -- Joint stiffness; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2016.12.013
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Three planar trusses were tested to study their progressive collapse resistance. Catenary action is the collapse resisting mechanism upon the loss of a diagonal. Welded joints may be simplified into pinned-joints with a continuous chord. Detrimental effect of excessive joint stiffness on collapse resistance is observed. Abstract: This paper presents an experimental study on the dynamic progressive collapse behavior of planar trusses. A specially designed member-breaking device has been invented to 'break' a predefined structural member suddenly, particularly a diagonal member in the experiments. Videogrammetric technique was adopted to obtain the full field 3D displacement of the remaining structure, and strain instrumentation was carefully used to monitor the internal forces of all members. In association with the experiments, finite-element simulations of the test trusses have also been performed, with extended analysis on the effect of removal of members at different locations. Experimental results in conjunction with the numerical analysis have shown that: (1) the truss with directly welded joints (specimen truss-WJ) was able to quickly regain balance upon member loss, and the load-redistributing capacity was provided mainly through catenary action developed in the bottom chord; (2) the truss with pinned joints (truss-PJ) behaved almost identically to truss-WJ, suggesting that when computational models of truss structures need to be developed to obtain structural responses under a collapse scenario, pinned-joints with continuous chord could be assumed; (3) the truss with rigid joints (truss-RJ) experienced progressive buckling of three diagonal members and was damaged severely, indicating a detrimental influence of excessive joint stiffness on the collapse resistance of trusses.