Research on dynamic response and deformation evolution of a rectangular recycled aggregate concrete-filled steel tubular column under small-equivalent loads and weak disturbances

To study the dynamic response and deformation evolution of the rectangular recycled aggregate concrete-filled steel tubular (RRACFST) column under small-equivalent loads and weak disturbances, the measuring methods of blasting and the arrangement of measuring points were precisely handled. Three contact explosion tests were conducted on the RRACFST column to obtain their failure modes, dynamic strains, and accelerations. The research results indicate that the range of 20-30g TNT equivalent represents the starting point and critical point of plastic deformation for the RRACFST column. When the explosive quantity increases incrementally under small-equivalent loads and weak disturbances, the radius and size of the explosion crater do not exhibit a linear relationship. The methods of explosive treatment under small-equivalent loads and weak disturbances adhere to the core principles of precision and quantification, meeting engineering requirements. This study provided a theoretical basis and experimental basis for the safety study of RRACFST columns structure under explosion load.