Flexural Behavior of Lapped Connections in Multi-span Cold-formed Z-purlins

Abstract

Aims: Study the flexural behavior of the lapped connections in multi span cold-formed steel Z sections systems. Study Design: The effect of overlap length of the lapped connections was investigated in order to achieve the optimum overlap length/depth ratio. Different bolts arrangements were studied to connect lap splice. Also, a new method using epoxy was supposed and studied to connect lap splice. The effect of web stiffening and flange stiffening of the lapped connection were also investigated in this study. Place and Duration of Study: The R.C. and Materials laboratory, Benha Faculty of Engineering, Benha University, Egypt, between February 2013 and May 2015. Methodology: Seventeen full scale specimens with lapped connections were prepared and experimentally tested taking into account the variables of this study. Results: The experimental results included ultimate load, vertical deflection at mid-span and mode of failure. Conclusion: As expected, the length of lapped connection clearly improved the flexural behavior of the tested specimens. The bolts arrangement at lap splice was very important in increasing the strength and stiffness of lapped connection. The experimental results showed that using epoxy was a practical and good method to connect lap splice. Both web stiffening and flange stiffening delayed the local buckling of lapped connection. However, the flange stiffening produced a more improvement of local buckling resistance.