Tensile Rate Effects in High Strength-High Ductility Concrete

Researchers at the University of Michigan have recently developed a new class of concrete, named High Strength-High Ductility Concrete (HSHDC), which possesses exceptional combination of compressive strength (> 150 MPa) and tensile ductility (> 3%) under quasi-static loads. The structural applications of HSHDC for withstanding extreme events, such as hurricanes, earthquakes, impacts, and blasts, require an understanding of its dynamic behavior at high strain rates. This research experimentally investigates the effects of strain rate (from 10− 4/s to 10/s) on the composite tensile properties and the micro-scale fiber/matrix interaction properties of HSHDC. A micromechanics-based scale-linking model is used to analytically explain the composite-scale rate effects based on the micro-scale rate effects. Due to the unique interactions between the Polyethylene fibers and densely packed ultra-high strength matrix of HSHDC, novel rate effects are revealed, which are expected to be foundational for the future development of this class of materials for improving infrastructure resilience.