XFEM Modelling and Experimental Observations of Foam Concrete Beam Externally-Bonded with KFRP Sheet

Abstract

This paper investigates the effect of KFRP composite sheets as a strengthening material in improving the loadcarrying resistance of lightweight foam concrete beams using a FEA modelling framework. The study employed three parametric strengthening schemes (i.e., KFRP length, woven architecture types and KFRP thickness). Twenty-seven beam specimens were tested, and respective failure modes and ultimate load at failure were discussed. All the strengthened beam specimens failed mostly in shear mode and, to a lesser extent, in FRP fracture. Despite the absence of de-bonding failure, improvement of strengthening using KFRP sheet technique was exhibited. Later, Extended Finite Element Method (XFEM) Modelling was incorporated following failure mode exhibited. Strength predictions incorporating the traction-separation relationship using XFEM techniques. Validation work with experimental datasets showed good agreements with average discrepancies of less than 10%. The numerical approach can be used as a strength prediction tool in concrete beams with externally bonded FRPs.

Application of Bilinear Softening Laws and Fracture Toughness of Foamed Concrete

“…The model showed good consistency at the ultimate load for both the the XFEM and CZM methods. Similar findings with global mesh size 2 were also reported by [46], while investigations by [47][48][49] involved global meshes with sizes of 0.01 mm, 0.125 mm, and between 0.5-1 mm, respectively. Meanwhile, a damage stabilization cohesive with a value of 1 × 10 −5 was also reported in [28,50,51].…”