Vol. 14, No. 2, pp. 142-165(2018)
A SIMPLE ANALYTICAL METHOD FOR EVALUATION OF FLEXIBLE
ROCKFALL BARRIER PART 2: APPLICATION AND FULL-SCALE TEST
Z.X. Yu1,2, Y.K. Qiao1, L. Zhao1*, H. Xu1, S.C. Zhao1,2 and Y.P. Liu3
1 School of Civil Engineering, Southwest Jiaotong University, Chengdu, China
2 National Engineering Laboratory for prevention and control of geological disasters in land transportation, Chengdu, China
3 Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
*(Corresponding author: E-mail:This email address is being protected from spambots. You need JavaScript enabled to view it.)
Received: 4 January 2017; Revised: 25 May 2017; Accepted: 5 June 2017
DOI:10.18057/IJASC.2018.14.2.2
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ABSTRACT
The companion paper proposed an analytical solution for design of flexible rockfall barrier undergoing large deflection. The part one also reported that the elongation of energy dissipating device plays an important role in buffer mechanism of the system. This paper further studies the governing factors on large deflection of flexible barrier system and then establishes a deflection-control-based mechanical model with improved buffer performance. The factors include the matching property between the energy dissipating device and the support rope, the motion interference during sliding along support ropes, overload protection from lateral support ropes. A prototype model with a nominal energy level of 2000 kJ was designed using the analytical method introduced in part one of the paper. Both full-scale test and numerical simulation were carried out to investigate the response of the prototype model under impact load. The results show that the motion interference and the braking effect during impact test are effectively controlled by the proposed deflection-control-based mechanical model, leading to an optimized design in terms of system buffer performance. Thus, this paper demonstrates the application of the analytical method presented in part one. The full-scale test and numerical simulation prove the validity and accuracy of the proposed method.
KEYWORDS
flexible barrier, buffer performance, rockfall, full-scale test, mechanical behavior, deflection control
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