Parametric study on the mechanical response of a flexible rockfall barrier

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Journal of Vibration and Shock ›› 2023, Vol. 42 ›› Issue (12) : 8-17.

ZHAO Lei，ZOU Dingfu，ZHANG Lijun，QI Xin，YU Zhixiang

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Abstract

Only specific impact condition is considered in verification tests of flexible rockfall barriers, which may not be the worst-case scenario in practice. Field investigations show that part of the products which pass the verification tests do not effectively achieve the expected protection target. Therefore, an in-depth research on the mechanical response of a flexible rockfall barrier under different impact conditions was carried out by numerical simulations. Firstly, the full-scale impact test of a flexible rockfall barrier with auxiliary supporting ropes was back-analysed. The numerical model was verified by comparing the breaking distance, rope forces and the elongation of energy dissipators. On this basis, parametrical simulations were carried out to investigate the effects of span number, impact location and post ends sliding characteristics on the mechanical response of the flexible rockfall barrier. The results showed that: the mechanical response of the flexible rockfall barrier was less affected by the number of spans; under the same impact condition, the internal force of the side post was more than twice that of the middle steel post, and was significantly affected by the impact location. In term of the side post, the impact position located at the side span is most unfavourable, and it may buckle even when the system passed the standard verification test; the internal force of supporting ropes will grow significantly with the increasing of the friction coefficient of post ends, and a safety factor of 2.0 was recommended for the design of supporting ropes.

Key words

flexible rockfall barrier ;numerical simulation / parametric research / impact mechanical response

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ZHAO Lei，ZOU Dingfu，ZHANG Lijun，QI Xin，YU Zhixiang. Parametric study on the mechanical response of a flexible rockfall barrier[J]. Journal of Vibration and Shock, 2023, 42(12): 8-17

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