Failure mechanism and mechanical mechanism of abrasive jet‐assisted mechanical crushing of reinforced concrete

Abstract Traditional concrete crushing methods have disadvantages such as low precision, high risk, dust, and noise. This paper proposes an abrasive jet‐assisted mechanical crushing method for reinforced concrete that improves crushing efficiency, reduces energy consumption, and minimizes pollution. The development of this technology is constrained by the problems of fluid–solid coupling and parameters, as well as the failure mechanism and mechanical properties of reinforced concrete that are still unclear. In this paper, a test system combining abrasive jet and mechanical crushing of reinforced concrete is established, and acoustic emission, electron microscope scanning, tomography, and other tests are used to study the failure mechanism of concrete crushing. The numerical model is set up by using smooth particle dynamics to further investigate the mechanical evolution of the abrasive jet‐assisted mechanical crushing of reinforced concrete. The results show that abrasive AWJ‐assisted mechanical crushing of reinforced concrete, compared to single mechanical crushing, exhibits stronger and more frequent acoustic emission energy and amplitude is stronger and more frequent, the spalling block becomes larger, and the CT scan shows that the phenomenon of cracks crossing and fusing to form a new crack occurs in the interior. Analyzed by numerical simulation, abrasive AWJ‐assisted mechanical crushing of reinforced concrete produces a bowl‐shaped crater on the surface caused by the shear breakage of the ring, and the stress transition occurs around the reinforcement bar that produces tensile stress damage. After the end of the crushing test, the reinforced concrete fails under the joint action of shear stress and compressive stress.