Synopsis
Recent research has led to an improvement in the properties of model reinforcement, but similitude of deformations, over the complete range of loading, andshear strength has not been achieved. It is well known that a number of size effects are due mainly to the properties of microconcrete because, in comparison with structural concrete, this material is stronger in tension and more ductile in compression. As a result of a detailed investigation into the compressive to tensile strength ratio and the stress-strain relationship of various model concrete mixes, a new type of microconcrete has been produced. The new mix is gap-graded, some of the coarsesand particles being replaced by glass beads, It has been tried in a number of model beams with an over-all depth of 30 mm and has given useful results.
