Tests for cushion performance of a protective layer with S-shaped steel joist and sandwich slab under rockfall impact
ZHANG Shan1，ZHNAG Jun-fa1，TAO Lei2，LIU Hao-zhao1
1. School of Civil Engineering and Architecture, Xi’an University of Technology, Xi’an 710048, China;
2.School of Water Resources and Hydro-Electric Engineering, Xi’an University of Technology, Xi’an 710048, China
To reduce wall damages of buildings and structures in alpine canyons due to rockfall impact, a protective layer scheme with combination of S-shaped steel and EPS foam sandwich slab was proposed. S-shape cold-formed thin-walled steel was designed and self-made. The proposed protective layer scheme was used on a RC slab supported at four corners, then a series of rockfall impact tests were conducted on this RC slab. The cushioning performance of the protective layer was studied mainly through observing the variation of rockfall impact force and support reaction forces at four corners of the RC slab with time. The results were compared with those without the protective layer. It was shown that the new protective layer makes the time duration of rockfall impacting the RC slab be lengthened 5 ~ 6 times, the biggest impact force decreases 50%, the average impact force decreases from the initial value to its 1/7 ~ 1/6, the maximum strain rate in the RC slab drops from105s -1 to 103 ~ 10-2s-1, the damage level of the RC slab due to rockfall impact is greatly reduced, so the proposed protective layer has a good cushion performance.
张山1，张俊发1，陶磊2，刘浩召1. S形钢龙骨-夹芯板防护层的落石冲击缓冲性能试验研究[J]. 振动与冲击, 2017, 36(24): 148-155.
ZHANG Shan1，ZHNAG Jun-fa1，TAO Lei2，LIU Hao-zhao1. Tests for cushion performance of a protective layer with S-shaped steel joist and sandwich slab under rockfall impact. JOURNAL OF VIBRATION AND SHOCK, 2017, 36(24): 148-155.
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