Mechanical behavior of reinforced concrete subjected to impact loading

摘要

Understanding the behavior of concrete and reinforced concrete at high strain rates is of critical importance in a range of application. The behavior of concrete and reinforced concrete at strain rates of the order of 10~4/s and pressure up to 1.5 GPa are studied experimentally. The concrete analyzed has the same composition and processing conditions as the matrix phase in the reinforced concrete. The dynamic compression experiments of reinforced concrete are carried out by one-stage light gas gun apparatus which subjects the reinforced concrete to deformation at strain rates of the order of 10~4/s with confining pressures of 1-1.5 GPa. The voltage-time signals are recorded by the manganin pressure gauges embedded in the target. The stress-strain curves of reinforced concrete with different impact velocities are obtained using Lagrangian analysis, from which the distribution regulations of other mechanical parameters such as specific internal energy and specific volume in the flow field are acquired. Experimental results indicate that the load-carrying capacities of concrete and reinforced concrete increase significantly with strain rate. The concrete and reinforced concrete are non-linear, rate-sensitive and pressure-dependent.