American Journal of Mechanics and Applications
Volume 7, Issue 3, September 2019, Pages: 56-63
Received: Aug. 22, 2019;
Published: Nov. 18, 2019
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Mei Xuefeng, Faculty of Geosciences and Environment Engineering, Southwest Jiaotong University, Chengdu, China
Hu Xiewen, Faculty of Geosciences and Environment Engineering, Southwest Jiaotong University, Chengdu, China; Engineering Laboratory Combined with National and Local of Spatial Information Technology of High Speed Railway Operation Safety, Southwest Jiaotong University, Chengdu, China
Wu Jianli, Faculty of Geosciences and Environment Engineering, Southwest Jiaotong University, Chengdu, China
Reinforced concrete (RC) panels are widely used in the prevention and control of rockfall disasters in mountainous areas. In order to avoid the rigid damage caused by rockfalls that directly impact RC panels, the energy dissipation layer is often added to cushion the impact of rockfalls. In order to study the dynamic response of RC panels to different cushion layers under impact, a series of rockfall tests are carried out based on outdoor test platform. At the same thickness, the maximum impact force of EPS and sand composite cushion reduces by 50% compared with that of sand cushion, and the impact contact time is obviously longer than that of sand. Under the same impact condition, the center position of EPS material is crushed and collapsed, and a large number of radial cracks occur. The composite cushion layer can effectively reduce the mid-span displacement of RC Panel. At the falling height of 3 m, 5 m and 7 m, respectively, the mid-span displacement of RC Panel decreases by 37% to 46%. When sand is used as the cushion layer, the visible cracks in the middle of RC span increase from the bottom to the top. At the falling height of 7 m, the strain rate of concrete ranges from 101 ms-1 to 102 ms-1, while the strain rate of Reinforced ranges from 102 ms-1 to 103m s-1. Therefore, EPS and sand composite cushion layer is superior to sand in terms of energy dissipation effect. Compared with large-scale cluster rockfall prevention, the composite cushion layer has more advantages in preventing and treating single rockfall because of its easy damage, high cost of maintenance and replacement.
Research on the RC Panel Experiments with Cushion Layer Upon Rockfall Impact, American Journal of Mechanics and Applications.
Vol. 7, No. 3,
2019, pp. 56-63.
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