Experimental study on the buffering mechanism of EPS bead-sand cushions under single and multiple impacts

• Published in: Geoenvironmental disasters Vol. 11; no. 1; pp. 31 - 15
• Main Authors: Ren, Feifan, Liu, Jiahao, Huang, Qiangqiang, Ding, Huan, Hu, Zhipeng, Wang, Guan
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 14-10-2024; Springer Nature B.V; SpringerOpen
• Subjects: Acceleration; Buffers; Civil engineering; Cushion; Cushions; Deformation; Design; Design optimization; Design theory; Earth and Environmental Science; Earth pressure; Earth Sciences; Emergency preparedness; Energy consumption; Environment; Environmental Science and Engineering; EPS beads; Geoecology/Natural Processes; Geography; Geology; Impact analysis; Impact force; Impact loads; Impact tests; Natural Hazards; Penetration depth; Rockfall; Sand; Stress concentration; UNESCO Chair on Geoenvironmental Disaster Reduction; Vibration; Vibration analysis; Earth pressure; EPS beads; Impact force; Cushion; Acceleration
• ISSN: 2197-8670; 2197-8670
• DOI: 10.1186/s40677-024-00298-1

As a main functional component of rock sheds in rockfall protection projects, traditional sand cushions have shortcomings such as heavy weight and weak buffering capacity. EPS bead-sand cushion can effectively solve these problems, but its buffering mechanism has not been fully revealed. In this study, a series of impact tests were carried out to investigate the performance of EPS bead-sand cushions with different EPS bead contents, and the evolutions of rockfall impact force, penetration depth, earth pressure, and slab vibration under single impact and multiple impacts were comparatively analyzed. The results show that with the addition of EPS beads, the maximum impact force, the peak earth pressure, and the vibration acceleration are significantly reduced. However, the cushion with high EPS bead content is at risk of being penetrated under high energy or multiple impacts, leading to excessive concentration of impact stresses. Furthermore, the EPS beads can alleviate the hardening of the sand cushion under impact through their deformation coordination, but excessive penetration should be prevented in the design of EPS bead-sand cushions. On this basis, combined with traditional sand cushion design theory, an estimation method for the maximum impact force applicable to EPS bead-sand cushion was proposed. The research results can provide a reference for the design and optimization of cushions in actual projects.