TY -的A2 -里佐,法比奥盟——Kurihashi Yusuke盟——Nonomura manuscript公司AU - Konno Hisashi PY - 2020 DA - 2020/12/23 TI -钢筋混凝土梁的抗冲击性行为恶化由于反复冻融SP - 7834765六世- 2020 AB -许多现有钢筋混凝土(RC)结构建造50多年前现在需要维护。特别是在寒冷,下雪的地区重要的冰系伤害恶化RC结构成为一个严重的问题。在这项研究中,落锤冲击试验进行调查RC梁的耐冲击行为退化冻坏。一个RC梁受到约900冻融循环模拟冲击试验的执行前的冰系伤害。梁的表面相当比例,和它的粗骨料被曝光。恶化的程度是评价超声传播速度的分布。得出了以下的结论。(1)钢筋混凝土梁的超声波传播速度是872次冻融循环后显著降低。在RC梁的上边缘,超声波传播速度下降从4000 m / s到1500 m / s在某些部分。这对应于一个相对动态弹性模量约为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 -