Analytical and experimental study on damping ratio of GRP‐reinforced glulam beams

Purpose – The purpose of this paper is to present weighted residual method (WRM) for evaluating damping ratio of unreinforced glued‐laminated (glulam) wood beams and also reinforced glulam beams with E‐glass reinforced epoxy polymer (GRP) plates.Design/methodology/approach – In this method, created error from the regression curve to the peak points of experimental displacement values is minimized. Several weight functions such as Galerkin weight function, Petrov‐Galerkin weight functions, and least square weight function are used for minimizing this error and results from these methods are compared to the existing methods as; logarithmic decrement analysis (LDA), Hilbert transform analysis (HTA), moving block analysis (MBA), and half power bandwidth (HPB).Findings – Because WRM tries to minimize the error function provided from differences between theoretical and experimental fitted curves, comparison among these methods indicate that proposed procedure is useful for any range of damping ratios and it giv...