Size effects in unreinforced and lightly reinforced concrete beams failing in flexure

Fracture-based models commonly use a characteristic length as the basis for determining size effects in concrete beams. The is related to fracture process zone and defined terms of properties. Semi-empirical constants are then developed accommodate any unidentified (geometric or crack bridging) parameters. However, reliance on semi-empirical factors can limit applicability different systems, concretes reinforcing materials. aim current work formulate an analytical effect model based solely fundamental material geometric particular focus unreinforced lightly reinforced beams that fail flexure due unstable propagation. proposed ’generalised’ approach mode-I behaviour includes bridging forces presence longitudinal reinforcement. theoretical expressions suggest shape beam, properties (where present) significantly influence length. Experimental investigations geometrically similar undertaken means initial validation. validation extended wider dataset existing experimental results literature. generalised able capture both strength mitigation inclusion This confirms holds promise could be expanded other quasi-brittle materials non-conventional