1 引言
岩石崩落(rockfall)是深部露天采矿工程和土木工程岩石边坡中经常遇到的问题。岩石崩落是指体积较小的分离块或系列块的自然向下运动,包括自由落体、弹跳、滚动和滑动。岩石崩落的形成受许多因素影响,例如岩体的不连续性,岩体的风化程度,地下水和地表水,冻融,外部爆破载荷和地震载荷等。岩石崩落轻者阻塞交通,重者造成了人员伤亡和设备毁坏。
因此,作为采矿工程师和土木工程师在设计边坡或施工边坡时必须考虑岩石崩落的因素。这个毕设训练的目的是为了让学生掌握最基本的岩石崩落分析过程和防护措施。下面简要描述为了达到这一目的建议使用的参考资料以及分析工具。
2 参考资料和分析工具
岩石崩落分析首推的参考资料是Dr. Hoek 的专著《Practical Rock Engineering》---“Analysis of rockfall hazards ”。其次,有许多这个论题的中文杂志论文和研究生毕业论文,建议有选择性地进行参考。尽管离散元(UDEC和PFC2D)可以进行岩石崩落分析,但由于时间关系,本次训练不使用这些工具,仅使用RocFall和RocPro3D。这两个软件使用的原理基本上一样,都能进行确定性分析和概率性分析。
3 防止岩石崩落的措施
在岩石崩落的运动轨迹确定后,需要提出相应的防护措施。从风险管理的角度来看,有主动防护和被动防护两种方式。被动防护一般在沉降区或径流区采用,如使用垂直网、集水围栏、导流坝等, 目的是最大程度地控制降水诱发的岩石崩落。与此相反,主动防护可以使用岩石锚杆、边坡阻挡系统、喷射混凝土等措施。其他的主动措施可能包括改变边坡的几何形状,使边坡脱水以及重新植被等。
4 扩展的参考文献
[1] Miller, S.M., Girard, J.M., and McHugh, E. (2000). Computer modeling of catch benches to mitigate rockfall hazards in open pit mines. Pacific Rocks 2000, Balkema, Rotterdam, pp. 539-545.
[2] Jones, C, J. Higgins, R. Andrew (2000). Colorado Rockfall Simulation Program (Computer Program) Version 4.0.
[3] Mavrouli, O., & Corominas, J. (2017). Comparing rockfall scar volumes and kinematically detachable rock masses. Engineering Geology, 219, 64-73.
[4] Lambert C, Thoeni K, Giacomini A, Casagrande D, Sloan S (2012) Rockfall hazard analysis from discrete fracture network modelling with finite persistence discontinuities. Rock Mech Rock Eng 45(5):871–884
[5] Kobayashi, Y., Harp, E. L. and. Hagawa, T. (1990) Simulation of rock falls triggered by earthquakes. Rock Mech. Rock Engng, 23(1), 1-20.
[6] Kovacevic, M. S., et al. (2012). "The Stupica Tunnel - Rockfall Protection." Road and Rail Infrastructure Ii: 789-795.
[7] Pfeiffer T.J. and Bowen T.D. (1989) Computer simulation of rockfalls. Bull. Ass. Eng. Geol. XXVI: 135-146.
[8] 亚 南 (1996) 斜坡崩塌落石的运动学分析与防护[硕士学位论文][D]. 成 都: 成 都 理 工 学 院.
[9] Stevens W D. Rocfall:a tool for probabilistic analysis,design of remedial measures and prediction of rockfalls[M.S. Thesis][D]. Ontario,Canada:University of Toronto,1998.
[10] Sadagah, B. H. (2008). "Application of a rockfall hazard rating system in rock slope cuts along a mountain road of South Western Saudi Arabia." Landslides and Engineered Slopes: From the Past to the Future, Vols 1 and 2: 901-906.
[11] Salciarini, D., et al. (2009). "Numerical approaches for rockfall analysis: a comparison." 18th World Imacs Congress and Modsim09 International Congress on Modelling and Simulation: 2706-2712.
[12] Vishal, V., et al. (2017). "Hazard assessment in rockfall-prone Himalayan slopes along National Highway-58, India: rating and simulation." Natural Hazards 85(1): 487-503.
[13] Gupta, V., et al. (2017). "Geomechanical characterisation of slopes for assessing rockfall hazards in the Upper Yamuna Valley, Northwest Higher Himalaya, India." Himalayan Geology 38(2): 156-170.
[14] Singh, P. K., et al. (2013). "The stability of road cut cliff face along SH-121: a case study." Natural Hazards 68(2): 497-507.
[15] Youssef, A. M., et al. (2015). "Assessment of rockfall hazard at Al-Noor Mountain, Makkah city (Saudi Arabia) using spatio-temporal remote sensing data and field investigation." Journal of African Earth Sciences 101: 309-321.
UDEC: 岩体边坡阶梯状节理模拟---一个操作指导
GIIC-UDEC操作教程(2)---岩石滚落
岩石崩落分析(Analysis of Rockfall)方法简述
落石防护路堤计算设计优化方法的开发
不稳定边坡的防护和治理措施
新的Cadanav方**---基于三维轨迹模拟的落石危险区域划分