Experimental study on dynamic splitting of recycled concrete using SHPB

Abstract

Abstract. To study the recycled concrete splitting tensile properties and fracture state with various recycled coarse aggregate replacement percentage (i.e. 0%, 25%, 50%, 75% and 100%), the dynamic splitting test of recycled concrete was carried out using large diameter (75 mm) split Hopkinson pressure bar (SHPB). The results show that the recycled concrete splitting tensile strength increases with the increase of loading rate, and the loading rate also affects the recycled concrete fracture state, which indicates that the recycled concrete has obvious rate sensitivity. The damage state of the recycled concrete is not only the destruction of the interface between coarse aggregate and cement mortar, but also associates with the fracture damage of aggregates. Under the same water cement ratio, when the replacement percentage of coarse aggregates is around 50%-75%, the gradation of natural and recycled coarse aggregate is optimal, and thus the splitting tensile strength is the largest. This study offers theoretical basis for the engineering applications of recycled concrete.

High strain rate behaviour of fiber reinforced concrete

“…The position of the specimen is shown in the Fig.1. This arrangement, which is known as the Brazilian test, or diametric compression test, is a typical indirect tensile test, which was developed to determine the tensile strength of brittle materials such as rock, ceramics and concrete [3][4][5][6]. Even this method was developed for the study of the fracture behaviour at quasi-static loading, numerical analysis, Antoun et al [7] found that the stress distribution in the dynamic Brazilian test was similar to the static test; therefore, they thought that the dynamic Brazilian test was an effective method to measure the tensile properties.…”