Variação dos efeitos das quedas de rochas em seções rodoviárias por modificações na seção transversal e nos elementos de proteção
DOI:
https://doi.org/10.24849/j.geot.2014.132.07Palavras-chave:
Quedas de rochas, martelo Schmidt, coeficientes de restituição, elementos de proteção contra quedas de rochasResumo
São apresentados alguns resultados de simulações de quedas de blocos em quatro seções rodoviárias, obtidas através das informações coletadas durante o projeto e execução do Lote 2 da rodovia RS471/BR153, localizada no Estado do Rio Grande do Sul (sul do Brasil). Definiram-se quatro condições de seção transversal para cada local, além de cinco elementos de proteção, e foram feitas combinações entre eles visando obter o melhor nível de desempenho sob cada condição, estabelecendo como parâmetro de comparação a frequência de invasão de blocos dentro da área de operação veicular. As simulações foram feitas com o programa RocFall, definindo o coeficiente de restituição normal (RN) para os materiais dos taludes mediante uma correlação entre este parâmetro e as leituras obtidas com o martelo Schmidt. A forte rugosidade superficial dos taludes motivou uma análise de sensibilidade considerando três condições e diferentes valores de RN visando obter a condição que melhor representasse a realidade.
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Referências
ASTM D 5873-05 (2005). Standard Test Method for Determination of Rock Hardness by Rebound Hammer. Annual Book of American Society for Testing and Materials 2005, 4p.
Aydin, A. (2009). ISRM Suggested Method for determination of the Schmidt hammer rebound hardness: Revised version. International Journal of Rock Mechanics & Mining Sciences, 46, pp.627-634.
Aydin, A.; Basu, A. (2005). The Schmidt hammer in rock material characterization. Engineering Geology, 81, pp.1-14.
Azzoni, A.; La Barbera, G.; Zaninetti, A. (1995). Analysis and Prediction of Rockfalls Using a Mathematical Model. International Journal of Rock Mechanics & Mining Sciences, 32, pp.709-724.
Basu, A; Aydin, A. (2004). A method for normalization of Schmidt hammer rebound values. International Journal of Rock Mechanics & Mining Sciences, 41, pp.1211-1214.
Buzzi, O.; Giacomini, A.; Spadari, M. (2011). Laboratory Investigation on High Values of Restitution Coefficients. Rock Mechanics and Rock Engineering, 45, pp.35-43.
Chau, K.T.; Wong, R.H.C.; Liu, J.; Wu, J.J. (1999). Shape effects on the coefficient of restitution during rockfall impacts. Ninth International Congress on Rock Mechanics, ISRM Congress, Paris, pp.541-544.
Chau, K.T.; Wong, R.H.C.; Wu, J.J. (2002). Coefficient of restitution and rotational motions of rockfalls impacts. International Journal of Rock Mechanics & Mining Sciences, 39, pp.69-77.
Cruden, D.M.; Varnes, D.J. (1996). Landslide types and processes. pp. 36-75. Em: Turner, A.K; Schuster, R.L. (Eds.). Landslides: Investigation and Mitigation. Special Report 247. Washington, D.C. Transportation Research Board, National Research Council, 673 p.
Deere, D.U.; Miller, R.P. (1966). Engineering classification and index properties for intact rock. Technical Report AFWL-TR-65-116. Albuquerque, N. M. Air Force Weapons Laboratory, 300 p.
Farrand, S.W. (2007). Rockfall Modelling Parameters and the Control Barrier at Stockton Mine, New Zealand. Christchurch, New Zealand. Master Thesis. Department of Geological Sciences. University of Canterbury, 207 p.
Federal Highway Administration – FHWA (2005). Analysis and design of wire mesh/cable net slope protection. Final Research Report WA-RS 612.1. Washington, 186 p.
Flórez-Gálvez, J.H. (2012). Condicionantes geotécnicos e análise de quedas de blocos rochosos da rodovia RS471/BR152, lote 2. 164 p. Dissertação (Mestrado em Engenharia) – Programa de Pós-Graduação em Engenharia Civil. Universidade Federal do Rio Grande do Sul.
Gerber, W. (2001). Guideline for the approval of rockfall protection kits. Environment in practice. Federal Office of the Environment (FOEN), Swiss Federal Institute for Forest, Snow and Landscape Research (SLF), Research Institute (WSL). Bern, 39 p. Disponível em: , Acesso em: 01 abr. 2012.
Giani, G.P. (1992). Rock Slope stability analysis. The Netherlands. Balkema Publishers, 345 p.
Giani, G.P.; Giacomini, A.; Migliazza, M.; Segalini, A. (2004). Experimental and Theoretical Studies to Improve Rock Fall Analysis and Protection Work Design. Rock Mechanics, 37, pp.369-389.
Gomes, Guilherme J.C. (2009). Avaliação do perigo relacionado à queda de blocos em rodovias. Ouro Preto. Dissertação (Mestrado em Geotecnia) – Programa de Pós-Graduação em Geotecnia. Universidade Federal de Ouro Preto, 136 p.
Guidicini, G; Nieble, C.M. (1984). Estabilidade de taludes naturais e de escavação. São Paulo. Editora Blucher. 194 p.
International Society for Rock Mechanics – ISRM (1978). Suggested methods for Determining Hardness and Abrasiveness of Rocks. International Journal of Rock Mechanics & Mining Sciences, 15, pp. 89-97.
Heidenreich, B. (2004). Small and half- scale experimental studies of rockfall impacts on sandy slopes. Thèse N° 3059 (Doctorat ès Sciences Techniques) – Faculté Environnement Naturel, Architectural et Construit. École Polytechnique Fédérale de Lausanne, 231 p.
Labiouse, V.; Heidenreich, B. (2009). Half-scale experimental study of rockfall impacts on sandy slopes. Natural Hazards and Earth System Sciences, 9, pp.1981-1993.
Lorentz, J. (2006). Étude de la capacité de dissipation sous impact d’une structure sandwich de protection contre les chutes de blocs rocheux. Ph.D. Thèse. Université Grenoble 1 – Joseph Fourier, Grenoble, France, 218 p.
Norrish, N.I.; Wyllie, D.C. (1996). Rock slope stability analysis, pp. 391-425. Em: Turner, A.K; Schuster, R.L. (Eds.). Landslides: Investigation and Mitigation. Special Report 247. Washington, D. C. Transportation Research Board, National Research Council, 673 p.
Peng. B. (2000). Rockfall Trajectory Analysis: Parameter Determination and Application. Christchurch, New Zealand. Master Thesis. Department of Geological Sciences. University of Canterbury. 199 p.
Pfeiffer T.J.; Bowen, T.D. (1989). Computer Simulation of Rockfalls. Bulletin of the Association of Engineering Geologists, 26, pp.136-146.
Pierson, L.A.; Gullixson, C.F. Chassie, R.G. (2001). Rockfall catchment area. Design guide. Final report SPR-3(032). Washington. Federal Highway Administration, 78 p.
Rayudu, D.N.P. (1997). Computer simulation of Rockfalls – Application to rockfalls at Fox Glacier, West Coast, New Zealand. Christchurch, New Zealand. Master Thesis. Department of Natural Resources Engineering. Lincoln University, 172 p.
Ritchie, A.M. (1963). Evaluation of Rockfall and its Control. Highway Research Record, 17, pp.13- 28.
Spadari, M.; Giacomini, A.; Buzzi, O.; Fityus, S.; Giani, G.P. (2011). In situ rockfall testing in New South Wales, Australia. International Journal of Rock Mechanics & Mining Sciences, 49, pp. 84-93.
Spang, R.M.; Sönser, T. (1995). Optimized Rockfall Protection by ROCKFALL. Proceedings of 8th International Congress of Rock Mechanics, Tokyo.
Spang, R.M.; Rautenstrauch, R.W. (1988). Empirical and mathematical approaches to rockfall protection and their practical applications. pp. 1237-1243. Em: Bonnard, C. (Ed.). Landslides: International Symposium on Landslides, 5. Rotterdam. Proceedings.
Schellenberg, K. (2008). On the design of rockfall protection galleries. D.Sc. Thesis. Eidgenössische Technische Hochschule Zürich. Zürich, Suiça, 177 p.
Stevens, W.D. (1998). Rocfall: A tool for probabilistic analysis, design of remedial measures and prediction of rockfalls. Toronto. 28 p. Thesis (Master of Applied Science) – Graduate Department of Civil Engineering. University of Toronto.
Wang, I-T.; Lee, C-Y. (2010). Influence of Slope Shape and Surface Roughness on the Moving Paths of a Single Rockfall. World Academy of Science, Engineering and Technology, 65, pp. 1021-1027.
Wu, S-S. (1985). Rockfall Evaluation by Computer Simulation. Transportation Research Record, 1031, pp.1-5.
