Mesoscopic numerical simulation of the dynamic mechanical behavior of concrete containing tunnel slag aggregates

• The mesoscopic model of concrete containing slag aggregates is established. • The dynamic mechanical properties of slag aggregate concrete are examined by the mesoscopic simulation method. • The strain rate effect of slag aggregate concrete is investigated, and the influence of the slag content on the dynamic mechanical properties of concrete is analyzed. The utilization of tunnel slag as concrete aggregate is an effective means of achieving resource recycling. This study employs a mesoscopic numerical simulation method to investigate the dynamic mechanical properties of concrete incorporating tunnel slag aggregates. First, a mesoscopic finite element model for slag aggregate concrete is established, and the model parameters are determined through quasi-static mechanical performance analysis. Subsequently, the impact compression (at strain rates ranging from 1 s −1 to 100 s −1 ) and splitting tensile (at impact velocities between 0.0375 m/s and 3.75 m/s) mechanical properties of slag aggregate concrete are investigated using the ANSYS/LS-DYNA approach. The numerical simulation results indicate that slag aggregate concrete exhibits a significant strain rate effect; under high strain rate conditions, the impact compression and splitting tensile strengths tend to increase with the rising content of the aggregates. Furthermore, enhancements in matrix strength significantly improve the dynamic properties of concrete, with an optimal tunnel slag aggregate volume fraction set at 40%.