STUDY ON THE BEHAVIOR OF PRECAST REINFORCED CONCRETE BEAMS UNDER IMPACT LOADING

To study the impact-resistant behavior of precast reinforced concrete beams (PC beams), five PC beams and one reinforced concrete beam (RC beam) were tested under free-falling drop-weights. The effects of different assembly locations and grouted sleeve compactness on the impact-resistant behavior of PC beams were investigated. The crack patterns, impact forces, reaction forces, displacement and overall deformation energy dissipation of the specimens were described in detail. The results obtained are as follows: 1) the impact location, assembly position and impact loading affect the failure types of the specimens together. Under the impact loading, the longer distance between the assembly position and impact position, the more similar the mechanical performance, including the contact stiffness, integral stiffness and damage, is to that of the RC beam; 2) under the impact loading, when the assembly position and impact location are the same, the local damage and stiffness degradation of the PC beam are more serious, and its overall deformation energy dissipation is not as large as the PC beams with other assembly positions or the RC beam. In this case, it is necessary to take reasonable measures to improve its ability to resist shock; 3) the influence of sleeve grouting compactness on the mechanical properties of the PC beams is significant. It will also affect the damage form and stiffness of the PC beams; 4) the boundary conditions of the PC beams' assembly location is the key to affect the numerical analysis.