Experimental and analytical investigation of crack development in composite reinforced laminated arch

This paper describes the analysis of a laminated timber arch radially reinforced with composite fiber rods to arrest crack growth. A laminated arch with a through crack was instrumented with crack propagations gages to detect crack growth and was tested experimentally. A finite element model was developed, which represented the laminated timber arch and the reinforcing rods, and used two dimensional interface elements to simulate crack extension. The arch was modeled with a flaw in the form of a through crack that was assumed to be sharp. Material properties of the arch and rods were determined experimentally, and the crack dimensions in the model were taken from the experimental arch, which was measured using an X-ray emitter with 33 μm resolution. The experimental results (deformations, strains and crack growth) were compared with the analyses. The model showed reasonable agreement with the experiment but an improved model is required to capture the behavior correctly. This paper demonstrates the possibilities in reinforcing wood structural members using high-strength composites and points to some experimental and analytical challenges.