Akademik Veri Yönetim Sistemi
Structures, cilt.86, 2026 (SCI-Expanded, Scopus)
It is well-known that shear failure is a collapse mechanism that is the riskiest, fastest, and catastrophic and occurs with no visible signs of damage or prior warning for reinforced concrete (RC) beams. Therefore, to prevent brittle shear failure, the RC beams should include sufficient shear reinforcement, such as stirrups, and be designed to have sufficient shear capacity. However, the RC beams' shear capacity becomes inadequate for various reasons. One of these reasons may be the acting of the impulsive impact load, which is uncommon and disregarded in the design phase on the RC beams. An experimental program was conducted to examine the impact behavior and failure mode of shear-deficient RC beams in the scope of the present study. Besides, it aims to investigate the effectiveness of the strengthening method using mechanical steel stitches (MSS) in improving the general behavior, failure mode, and performance of shear-deficient RC beams exposed to impact load. In the experimental study, the impact loading energy level applied to RC beams with insufficient shear strength, the impactor geometry to which the impact loading is applied and the spacing of the MSS elements placed externally on the beams for strengthening purposes were investigated as variables. The time histories of the accelerations, displacements, and impact loads were measured. They were interpreted how they are affected by experimental variables examined in the experimental study. Furthermore, the finite element model of the specimens was generated in the LS-DYNA software, and the experimental and numerical results were compared by performing finite element analysis in terms of failure modes and general behavior. The strengthening method applied to RC beams with insufficient shear strength using the MSS technique generally improved the behavior of RC beams under impact loading, increased their performance, increased the maximum acceleration values by an average of 37%, and reduced the maximum and permanent residual displacement values by an average of 107% and 240%, respectively.