SLOPE MASS RATING DAN STABILITAS LERENG BATUPASIR FORMASI BALANGBARU DUSUN PALUDDA DESA PATAPPA KECAMATAN PUJANANTING KABUPATEN BARRU

Abstract The main road to the Parangtritis Beach tourism site in the southern Yogyakarta Province, Indonesia, has full of local and economic activities. The road was made mainly by karst mountains cutting and resulting in almost vertical long and high slopes by its side. Rockfall is being the most potential hazards occurred in this area. The purpose of this study is to determine the rockfalls hazard assessment along the main road using Slope Mass Rating (SMR) analysis. Parameters used in rockfall hazard assessment are SMR with additional valuation from the slope height and the block size. The necessary data of each parameter obtained by direct measurement and the uniaxial compressive strength test in the laboratory. Geomechanics analysis, stereographic projection analysis, and hazard parameters weighting are needed to produce research results in form Rockfall Hazard Zonation Map in the research location. The results showed that the largest percentage of rockfalls hazard class is very low class, with 83,83% of the total hazard classes, associated with normal SMR score (51,66 – 51,75), slope height between 2,85 – 4,57 m, and block size 0,2 – 0,3 m. Followed by intermediate class with 7,16% of the total hazard classes with very bad to bad SMR score (5,82 – 38,15), slope height between 4,26 – 8,96 m, and block size 0,3 – 1,0 m. In the third position followed by a low class with 4,28% of the total hazard classes with bad to normal SMR score (31,17 – 53,03), slope height between 3,52 – 5,28 m, and block size 0,2 – 0,7 m. The last position was taken by high class with 4,19% of the total hazard classes with very bad to bad SMR score (18,31 – 36,50), slope height between 3,62 – 7,82 m, and block size 0,7 – 1,3 m. The SMR analysis also identified the influence of rock types with the rockfall occurrence. Hazard zonation map verification showed a congeniality with the results of rockfalls quantity inventory in the research area.

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Uso da fotogrametria digital terrestre na classificação de maciços rochosos fraturados.

Revista de Geociências do Nordeste ◽

10.21680/2447-3359.2021v7n2id23403 ◽

2021 ◽

pp. 111-122

Author(s):

Saulo Nunes Sant'Anna ◽

Luis De Almeida Prado Bacellar ◽

Pedro Manuel Alameda-Hernández

Keyword(s):

Minas Gerais ◽

Slope Mass Rating ◽

Belo Horizonte

O presente trabalho visa discutir o uso de métodos de aquisição de dados geotécnicos de maciços rochosos. A área de estudo é uma pedreira de brita desativada, localizada na cidade de Belo Horizonte (Minas Gerais, Brasil), onde afloram gnaisses migmatizados, com constante queda de blocos. Os métodos de aquisição empregados foram o tradicional mapeamento de talude e o levantamento remoto por fotogrametria digital terrestre. A classificação de maciços Slope Mass Rating (SMR) foi aplicada. Os resultados evidenciaram diferenças nos ranges de detecção de estruturas e a fotogrametria se mostrou mais completa, com mais dados de descontinuidades do que o mapeamento tradicional, com exceção das estruturas oblíquas ao talude. Esta deficiência se explica pelo fato do talude estudado ser subvertical, sem reentrâncias e saliências, que permitem muitas vezes a detecção dos traços de descontinuidades e não dos planos. Contudo, mesmo nestes casos, a fotogrametria mostrou-se importante, por permitir a caracterização de todo talude, impossível pelo método tradicional. A classificação SMR mostrou baixos valores, indicando instabilidade por rupturas planares e em cunha do maciço em alguns pontos, o que coincide com as frequentes quedas de blocos.

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Slope mass rating of rock slopes of the Malekhu River, central Nepal Lesser Himalaya

Journal of Nepal Geological Society ◽

10.3126/jngs.v47i1.23102 ◽

2014 ◽

Vol 47 (1) ◽

pp. 36-46

Author(s):

Naresh Kazi Tamrakar ◽

Jaya Laxmi Singh

Keyword(s):

Rock Mass ◽

Slope Stability ◽

Failure Mode ◽

Rock Mass Rating ◽

Rock Slopes ◽

Plane Failure ◽

Central Nepal ◽

Slope Mass Rating ◽

Unstable Slope ◽

Rock Mass Slopes

The Malekhu River is one of the major tributaries of the Trishuli Ganga River fl owing from the south in Malekhu region, central Nepal. Riverbank slope stability is a topic of concern as rock mass condition and slope stability of riverbank slopes are important parameters for riverbank erodibility. Fourteen sites in the Malekhu River were selected for rock mass rating (RMR) and then slope mass rating (SMR) by using a graphic method. The potentially vulnerable sites were identifi ed after conducting field study in different slopes. The results indicate that there occur modes of failures ranging from stable (good rock mass) to partially stable (normal rock mass) in all the study sites. The unstable (bad rock mass) and completely unstable (very bad rock mass) slopes are, however, distributed only in some slopes. The unstable slope of plane failure mode is Ka1, whereas the completely unstable slopes of plane failure mode are Rb2, Ml1 Slope 1 and Ml2. The unstable slope of toppling failure mode is Ml2. When wedge failure mode is considered, the slopes at Ti1 and Ka1 are unstable while the slopes at Kh1, Ka1, Ml1 Slope 1 are completely unstable. The rock slopes with unstable to completely unstable states are considered bad (SMR Class IV: 21–40) to very bad (SMR Class V: 0–20) rock mass with fair to poor rock mass rating, respectively. These bad to very bad rock mass slopes are vulnerable to slope movements and river erosion, and they require mitigative measures.

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