Numerical simulation of shear behavior of scaled GFRP reinforced concrete beams without stirrups using lattice discrete particle model

There is extensive experimental evidence of the decrease in shear stress at failure at increasing size (i.e., effective depth) in glass fiber-reinforced polymer (GFRP) reinforced concrete (RC) beams and one-way slabs. An important practical implication is that extrapolating strength values from typical laboratory-scaled experiments to design larger members may be misleading. The complexity of the underlying mechanics is reflected in the lack of commercially available numerical tools that enable one to reliably estimate strength irrespective of beam size. This paper reports on research on the use of an experimentally validated Lattice Discrete Particle Model (LDPM) for concrete to numerically simulate the response of scaled slender GFRP RC beams without stirrups. The LDPM is enlisted to capture size effect for beams with an effective depth in the range 146-292 mm, and exhibiting a size effect in excess of 60%. The simulation results accurately estimate the load-deflection response, strength, and failure mode of the beams irrespective of size.