TY - Jour A2 - Rizzo，Fabio Au - Kurihashi，Yusuke Au - Nonomura，Yoshinori Au - Konno，Hisashi Py - 2020 Da - 2020/12/23 Ti - 钢筋混凝土梁的抗冲击性能由于反复冻结和解冻SP而劣化- 7834765 VL - 2020 AB - 许多现有的钢筋混凝土（RC）结构在50多年前构建现在需要维护。这在寒冷的雪域区域尤其如此，其中RC结构的显着霜冻损坏变得严重问题。在这项研究中，进行了降低的抗撞击试验以研究RC光束通过霜冻损伤降解的抗冲击性能。RC光束经过大约900个冻融循环，以在执行冲击试验之前模拟霜冻损伤。光束的表面显着缩放，并且暴露出粗骨料。通过超声波传播速度的分布评估劣化程度。得出了以下结论。（1）在872个冷冻解冻循环后，RC梁的超声波传播速度显着降低。在RC光束的上边缘处，超声波传播速度在某些部件中从4,000米/秒降低至1,500米/秒。 This corresponds to a relative dynamic elastic modulus of approximately 14%. (2) The residual deflection of RC beams with frost damage increased at most by 20% compared with beams without frost damage. The increase in residual deflection was primarily related to the peeling of concrete at the collision site and the opening of multiple bending cracks. (3) According to the existing residual deflection calculation formula, an increase of 20% in the residual deflection corresponds to a decrease of about 17% in the bending capacity of the RC beam. When the relationship between the degree of frost damage deterioration and the impact resistance of RC structures is defined, existing structures subjected to accidental impact force from rockfalls are safer and can be maintained more efficiently. SN - 1070-9622 UR - https://doi.org/10.1155/2020/7834765 DO - 10.1155/2020/7834765 JF - Shock and Vibration PB - Hindawi KW - ER -