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Zhao, Zhi Peng, and Jun Chao Zhi. "Application and Improvement of Rock Quality Designation (RQD)." Applied Mechanics and Materials 744-746 (March 2015): 1371–73. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.1371.
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When using Rock Quality Designation (RQD) method to evaluate rock mass integrity, the premises are often neglected and there are some limitations in RQD method. This study proposes a hole section statistical method and a rock block coefficient to supplement and improve the limitations of RQD method. The accuracy is verified by applying it to a reservoir.
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Eissa Elsayed, A., and Zekâi Sen. "Probabilistic simulation of rock quality designation (RQD)." Bulletin of the International Association of Engineering Geology 43, no. 1 (April 1991): 31–40. http://dx.doi.org/10.1007/bf02590168.
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Pells, P. J., Z. T. Bieniawski, S. R. Hencher, and S. E. Pells. "Rock quality designation (RQD): time to rest in peace." Canadian Geotechnical Journal 54, no. 6 (June 2017): 825–34. http://dx.doi.org/10.1139/cgj-2016-0012.
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Rock quality designation (RQD) was introduced by Don Deere in the mid-1960s as a means of using diamond core to classify rock for engineering purposes. Subsequently, it was incorporated into the rock mass rating (RMR) and Q-system classification methods that, worldwide, now play substantial roles in rock mechanics design, whether for tunnels, foundations, rock slopes or rock excavation. It is shown that a key facet of the definition of RQD is ignored in many parts of the world, and it is noted that there are several inherent limitations to the use of RQD. Based on mapping of rock formations by 17 independent professionals at different locations in Australia and South Africa, it is shown that differences in assessed RQD values result in significant errors in computed RMR and Q ratings, and also in geological strength index (GSI) and mining rock mass rating (MRMR). The introduction of a look-up chart for assessing GSI has effectively removed the need to measure, or estimate, RQD. It has been found that GSI values derived from the look-up chart are as valid as those derived by calculation from the original component parameters, and are satisfactorily consistent between professionals from diverse backgrounds. The look-up charts provide a quick and appropriate means of assessing GSI from exposures. GSI is, in turn, a useful rock mass strength index; one new application is presented for assessing potential erosion of unlined spillways in rock. Incorporation of RQD within the RMR and Q classification systems was a matter of historical development, and its incorporation into rock mass classifications is no longer necessary.
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Salaamah, Ainul Fatayaatis, Teuku Faisal Fathani, and Wahyu Wilopo. "Correlation of P-wave Velocity with Rock Quality Designation (RQD) in Volcanic Rocks." Journal of Applied Geology 3, no. 2 (August 7, 2019): 11. http://dx.doi.org/10.22146/jag.48594.
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One important part of rock mass investigation is the geomechanical assessment in terms of rock mass classification systems. Rock mass classification is one of themost efficient methods in rock mechanics to provide a basic understanding of rock masscharacterization. Rock mass properties can be determined by a seismic refraction surveyas an indirect geophysical assessment. In this study, the P-wave velocity from seismicrefraction was compared with the Rock Quality Designation (RQD) from the boreholes.The empirical correlation between the RQD and the P-wave velocity was found by usingthe linear regression analysis. The RQD value estimated from the P-wave velocity can beapplied for tropical environment study with geological conditions of volcanic rocks. This study helps to estimate and predict the subsurface rock quality, to reduce investigation costs, and to improve understanding of subsurface rock quality.
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Chen, Qingfa, Tingchang Yin, and Hangyu Jia. "Selection of Optimal Threshold of Generalised Rock Quality Designation Based on Modified Blockiness Index." Advances in Civil Engineering 2019 (January 10, 2019): 1–11. http://dx.doi.org/10.1155/2019/1340549.
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Rock quality designation (RQD) is a critical index for quantifying the degree of rock mass jointing; it is widely used for evaluating the qualities and stabilities of engineering rock masses. However, the use of traditional RQD may yield inaccurate assessments because only core pieces longer than 100 mm are counted. To enhance the utility of RQD, generalised RQD was introduced. Based on the modified blockiness index (MBi), the determination of the optimal threshold of generalised RQD was performed. In this work, 35 types of hypothetical three-dimensional joint network models were constructed, and their generalised RQD values (with different thresholds) and MBi values were measured. The correlation between the standard ratings of MBi and RQD was assessed; based on this correlation, the theoretical RQD values of the 35 models were derived. The reasonable thresholds of the generalised RQD were determined according to the theoretical RQD values, and the optimal threshold of generalised RQD was obtained using the variation coefficient and anisotropy index of the jointing degree. The discrepancy between the results produced using traditional and generalised RQDs was discussed. Finally, an actual case study was conducted, and the results indicate that the generalised RQD associated with the optimal threshold determined in this study can properly quantify the degree of jointing of a given rock mass.
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Jun, Lin, Sha Peng, Gao Shuyu, and Ni Jiji. "Characteristics Analysis of Generalized Rock Quality Designation (RQD) Based on Degree of Joint Development." Advances in Civil Engineering 2021 (August 4, 2021): 1–13. http://dx.doi.org/10.1155/2021/4702348.
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Rock quality designation (RQD) is widely adopted as a fundamental tool in characterizing rock masses since it was devised in 1964. Since the conventional RQD calculation is limited due to its dependence on the selected threshold, previous research introduced generalized RQD to adequately reflect the anisotropy and scale effect of RQD. However, the influence of the joint development inside rock mass on generalized RQD remains unclear. The objective of this work is to investigate characteristics of the generalized RQD in view of different development degrees of discontinuities in rock mass, including spacing (density) and trace length. Three-dimensional fracture network modelling is employed to simulate the actual rock mass of open-pit iron mine in China. Virtual scanlines are set to obtain RQD values in different directions. The results primarily show that the generalized RQD should be introduced to calculate the RQD with different thresholds to fully reflect the anisotropy of rock mass. The optimal threshold can be obtained based on an anisotropic coefficient, which is defined by (RQDmax-RQDmin). It is also indicated that the fracture spacing has a great influence on both the anisotropy of RQD and the selection of the optimal threshold. The optimal threshold of the generalized RQD increases with the increase in the fracture spacing. In addition, the scale effect of RQD in different models is discussed by changing the length of the scanlines. The longer the scanlines we set, the more stable RQD value can be obtained in the model. It is recommended to fit much longer scanline to get realistic RQD in heavily fractured rock mass.
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Yasrebi, Amir Bijan, Andrew Wetherelt, Patrick J. Foster, Peyman Afzal, John Coggan, and Dariush Kaveh Ahangaran. "APPLICATION OF RQD-NUMBER AND RQD-VOLUME MULTIFRACTAL MODELLING TO DELINEATE ROCK MASS CHARACTERISATION IN KAHANG Cu-Mo PORPHYRY DEPOSIT, CENTRAL IRAN / ZASTOSOWANIE METOD MODELOWANIA NUMERYCZNEGO ORAZ MODELOWANIA FRAKTALNEGO DO ANALIZY JAKOŚCI SKAŁ W CELU OKREŚLENIA CHARAKTERYSTYKI GÓROTWORU W OBSZARZE ZŁOŻA Cu-Mo W KAHANG, ŚRODKOWY IRAN." Archives of Mining Sciences 58, no. 4 (December 1, 2013): 1023–35. http://dx.doi.org/10.2478/amsc-2013-0071.
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Abstract Identification of rock mass properties in terms of Rock Quality Designation (RQD) plays a significant role in mine planning and design. This study aims to separate the rock mass characterisation based on RQD data analysed from 48 boreholes in Kahang Cu-Mo porphyry deposit situated in the central Iran utilising RQD-Volume (RQD-V) and RQD-Number (RQD-N) fractal models. The log-log plots for RQD-V and RQD-N models show four rock mass populations defined by RQD thresholds of 3.55, 25.12 and 89.12% and 10.47, 41.68 and 83.17% respectively which represent very poor, poor, good and excellent rocks based on Deere and Miller rock classification. The RQD-V and RQD-N models indicate that the excellent rocks are situated in the NW and central parts of this deposit however, the good rocks are located in the most parts of the deposit. The results of validation of the fractal models with the RQD block model show that the RQD-N fractal model of excellent rock quality is better than the RQD-V fractal model of the same rock quality. Correlation between results of the fractal and the geological models illustrates that the excellent rocks are associated with porphyric quartz diorite (PQD) units. The results reveal that there is a multifractal nature in rock characterisation with respect to RQD for the Kahang deposit. The proposed fractal model can be intended for the better understanding of the rock quality for purpose of determination of the final pit slope.
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Zhang, Lianyang. "Determination and applications of rock quality designation (RQD)." Journal of Rock Mechanics and Geotechnical Engineering 8, no. 3 (June 2016): 389–97. http://dx.doi.org/10.1016/j.jrmge.2015.11.008.
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Madani, Nasser, Saffet Yagiz, and Amoussou Coffi Adoko. "Spatial Mapping of the Rock Quality Designation Using Multi-Gaussian Kriging Method." Minerals 8, no. 11 (November 15, 2018): 530. http://dx.doi.org/10.3390/min8110530.
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The rock quality designation is an important input for the analysis and design of rock structures as reliable spatial modeling of the rock quality designation (RQD) can assist in designing and planning mines more efficiently. The aim of this paper is to model the spatial distribution of the RQD using the multi-Gaussian kriging approach as an alternative to the non-linear geostatistical technique which has shown some limitations. To this end, 470 RQD datasets were collected from 9 boreholes pertaining to the Gazestan ore deposit in Iran. The datasets were declustered then transformed into Gaussian distribution. To ensure the model spatial continuity, variogram analysis was first performed. The elevation 150 m with a grid of 5 m × 5 m × 5 m was selected to illustrate the methodology. Surface maps showing the RQD classes (very poor, poor, fair, good, and very good) with their associated probability were established. A cross-validation method was used to check the obtained model. The validation results indicated good prediction of the local variability. In addition, the associated uncertainty was quantified on the basis of the conditional distributions and the accuracy plot agreed with the overall results. It is concluded that the proposed model could be used to produce a reliable RQD map.
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Zhang, Lianyang. "Prediction of end-bearing capacity of rock-socketed shafts considering rock quality designation (RQD)." Canadian Geotechnical Journal 47, no. 10 (October 2010): 1071–84. http://dx.doi.org/10.1139/t10-016.
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Existing empirical methods for determining the end-bearing capacity, qmax, use empirical relations between qmax and the unconfined compressive strength of intact rock, σc. As rock-socketed shafts are supported by the rock mass, not just the intact rock, one should consider not only the intact rock properties, but also the influence of discontinuities on rock mass properties when determining qmax. Although semi-empirical and analytical methods have been developed that can consider the effect of discontinuities, they are more complicated than the empirical relations and require information about discontinuities that is often not available or difficult to obtain in engineering practice. In this paper, an empirical relation between qmax and the unconfined compressive strength of rock mass, σcm, is developed. The new empirical relation explicitly considers the effect of discontinuities represented by rock quality designation (RQD), which is the parameter normally obtained in engineering practice. The accuracy of the expression for estimating σcm based on RQD is verified by comparing its estimation values with those from the existing empirical expressions based on rock mass classification. Two examples are presented to show the application of the newly developed empirical relation between qmax and σcm.
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Koutsoftas, Demetrious C. "Discussion of “Rock quality designation (RQD): time to rest in peace”." Canadian Geotechnical Journal 55, no. 4 (April 2018): 584–92. http://dx.doi.org/10.1139/cgj-2017-0497.
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Vavro, M., K. Souček, L. Staš, P. Waclawik, L. Vavro, P. Konicek, and J. Ptáček. "Application of alternative methods for determination of rock quality designation (RQD) index: a case study from the Rožná I uranium mine, Strážek Moldanubicum, Bohemian Massif, Czech Republic." Canadian Geotechnical Journal 52, no. 10 (October 2015): 1466–76. http://dx.doi.org/10.1139/cgj-2014-0377.
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A comparison of rock quality designation (RQD) parameters obtained by drill core analysis and the RQD determined using alternative methods is presented using metamorphic rocks such as migmatized gneisses, migmatites, and amphibolites. Methods of borehole–wall imaging using high-resolution acoustic logging, optical televiewer, and simple video inspection as well as the structural analysis of exploration drift walls oriented subparallel to the analysed boreholes are used for alternatively evaluated RQD values. Results show that, in most cases, the RQD index measured directly on a drill core section reaches lower values (about 10%–30%) than the RQD evaluated by alternative methods. Significant differences in determination of the rock mass failure degree using classical and alternative methods may occur, especially in sections with higher frequency of the metamorphic foliation planes created by biotite-rich bands or by dark-coloured melanosome layers. The nature of biotite itself is favourable for the creation of pre-disposed jointing planes, in which the increased drill core disintegration caused by drilling technology or core handling can occur. Results show it is highly appropriate to make these comparisons on a larger scale and thus verify whether the observed differences affect the qualitative classification of the rock mass.
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Palmstrom, Arild. "Measurements of and correlations between block size and rock quality designation (RQD)." Tunnelling and Underground Space Technology 20, no. 4 (July 2005): 362–77. http://dx.doi.org/10.1016/j.tust.2005.01.005.
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Madani Esfahani, Nasser, and Omid Asghari. "Fault detection in 3D by sequential Gaussian simulation of Rock Quality Designation (RQD)." Arabian Journal of Geosciences 6, no. 10 (July 26, 2012): 3737–47. http://dx.doi.org/10.1007/s12517-012-0633-3.
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Canello, Vivian Athaydes, Josiele Patias, and Lázaro Valentim Zuquette. "Interpolação 3D de dados de Rock Quality Designation: Barragem de Itaipu, Paraná, Brasil." Geologia USP. Série Científica 20, no. 3 (September 29, 2020): 31–46. http://dx.doi.org/10.11606/issn.2316-9095.v20-159737.
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Este trabalho apresenta os resultados da aplicação de método computacional para interpolação tridimensional de dados de Rock Quality Designation (RQD) obtidos a partir de um conjunto de 143 sondagens rotativas, que foram realizadas na fase de investigação geológico-geotécnica para a construção da Barragem de Itaipu, localizada no rio Paraná, na fronteira entre o Brasil e o Paraguai, inserida no contexto geológico dos derrames basálticos da Formação Serra Geral. As interpolações foram desenvolvidas no programa Geographic Resources Analysis Support System (GRASS) utilizando o método numérico spline regularizado com tensão (RST). A interpolação foi desenvolvida para um volume de 28.107 m3 a partir de 4.736 dados de entrada obtidos de 143 sondagens rotativas e considerando voxel 3D com resolução horizontal de 25 m e vertical de 3 m, que gerou cerca de 149.330 voxels, resultando em uma média de dados de entrada de 0,032/voxel. Os dados de entrada de RQD apresentaram média aproximada de 80, mediana 87, desvio padrão 23, coeficiente de variação de cerca de 30% e variância de 529; enquanto os dados interpolados resultaram em média 74, coeficiente de variação de 27%, variância de 400 e desvio padrão 20. O resultado da interpolação mostrou que o método utilizado é eficiente e os programas GRASS e PARAVIEW adequados e de fácil domínio para estudos de interpolação. Por outro lado, reforçou que apesar da quantidade de dados iniciais, a distribuição espacial dos dados de entrada interfere na interpolação, o que reforça a importância de um plano de investigação geológico-geotécnico adequado para obter um zoneamento com baixa incerteza.
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Зарьяб, Абдулхалим, Мохаммад Ибрагим Наджаф, and Мохаммад Зия Джамал. "Анализ инженерных свойств горных пород участка плотины Шах-и-Арус, Кабул, Афгани." Central Asian Journal of Water Research 5, no. 1 (April 15, 2020): 35–48. http://dx.doi.org/10.29258/cajwr/2019-r1.v5-1/35-48.rus.
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В настоящее время на реке Шакардара примерно в 22 км к северо-западу от г. Кабул, Афганистан, ведется строительство плотины Шах-и-Арус. Ее высота и длина составляют 77,5 м и 303 м, соответственно, а объем водохранилища оценивается примерно в 9,38 млн м 3 . Данное многоцелевое сооружение возводится из роликового уплотненного бетона (RCC) и предназначено для хранения оросительной воды, сдерживания наводнений и выработки электроэнергии. Плотина располагается в тектонически активной зоне, чем обусловливается значительное воздействие на нее тектонических процессов. В настоящей статье представлены результаты сопоставления показателей нарушенности горных пород (Rock Quality Designation, RQD) и параметров Люжона, основанных на обзоре и анализе материалов первоначальных инженерно-геологических изысканий и дополнительных полевых наблюдений. Результаты значений Люжона и показателей RQD прошли статистически-графическую оценку, и далее данные полученных графиков были сопоставлены со всеми другими естественными условиями зоны строительства плотины. Полученные результаты указывают на то, что комплекс природных условий в определенной степени характеризуется взаимосвязью между значениями Люжона и параметрами RQD. Кроме этого, массив горных пород основания плотины был охарактеризован в соответствии с классификацией скальной породы RMR (Rock Mass Rating).
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Lei, Jin Sheng, Lei Bao, Liang Wen, and Jian Fei Chen. "Application of Improved Gray Correlation Analysis Model to the Estimation of Country Rock Stability." Advanced Materials Research 594-597 (November 2012): 28–32. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.28.
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The estimation of country rock stability in underground engineering is the important basis for carrying out engineering design and formulating corresponding engineering measures. The interval form of quality standard, the value of resolution coefficient ρ and the weight of correlation degree are seldom takend consideration by the traditional gray correlation analysis model, an improved gray correlation analysis model is used to analyze the five indices of influencing the country rock stability: rock quality designation RQD, moisture compressive strength Rw, integrity coefficient Kv, structure surface strength coefficient Kf, groundwater seepage measurement W/L. The results show that the improved correlation analysis model is superior in its objectivity and applicability as well as certain practical value in evaluating country rock stability or other evaluation problems.
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Nkpadobi, Johnbosco Ikenna, John Kuna Raj, and Tham Fatt Ng. "Classification of cut slopes in weathered meta-sedimentary bedrocks." Earth Sciences Research Journal 20, no. 2 (July 1, 2016): 1. http://dx.doi.org/10.15446/esrj.v20n2.52781.
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In order of abundance, the meta-sedimentary rocks along Pos Selim Highway in Perak state Malaysia comprise quartz mica schist, graphitic schist, and quartzite layers. Field investigations revealed that these meta-sedimentary rocks have gradational weathering profile based on differences particularly in textures, hardness, lateral changes in colour, and consistency of material extension. The results from uniaxial compressive strength tests confirmed field observations whereby failure occurred mostly on outcrops having joints almost perpendicular to foliation. From the kinematic analyses, the investigated cut slopes are unstable with possibilities of wedge and planar failures. Application of rock mass classification schemes including Rock Quality Designation (RQD) and Rock Mass Rating (RMR) yielded almost similar poor to good quality ranges for each investigated rock mass. While Slope Mass Rating (SMR) classified the cut slopes from stable to unstable slopes, this study categorized them into one actively unstable, four marginally stable and five stable slopes. ResumenEn orden de abundancia, las rocas metasedimentarias a lo largo de la carretera Pos Selim, en el estado Perak de Malasia, se componen de esquistos de cuarzo mica, esquistos de grafito y capas de cuarzo. Las investigaciones de campo revelan que estas rocas metasedimentarias tienen perfiles de meteorización progresiva basados en diferencias particulares como textura, dureza, cambios laterales de color y consistencia del material de extensión. Los resultados de los ensayos uniaxiales de esfuerzo de compresión confirmaron las observaciones de campo por las cuales se estableció que las fallas ocurrieron mayormente en los afloramientos con coyunturas perpendiculares hacia la foliación. De los análisis cinemáticos se desprende que los taludes de corte investigados son inestables con posibilidades de fallas planas y de cuña. La utilización de esquemas de clasificación rocosa como el índice RQD (del inglés Rock Quality Designation) y la clasificación geomecánica de Bienawski o RMR (del inglés Rock Mass Rating) evidencia rangos similares de baja y buena calidad para cada masa rocosa estudiada. Mientras que el índice de taludes SMR (del inglés Slope Mass Rating) clasificó los taludes de corte de estables a inestables, este estudio los categorizó de uno activamente inestable, cuatro marginalmente estables y cinco estables.
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Syaeful, Heri, and Dhatu Kamajati. "Analisis Karakteristik Massa Batuan di Sektor Lemajung, Kalan, Kalimantan Barat." EKSPLORIUM 36, no. 1 (May 30, 2015): 17. http://dx.doi.org/10.17146/eksplorium.2015.36.1.2768.
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Karakterisasi massa batuan diperlukan dalam suatu rancangan bukaan batuan, dimana perhitungan sifat-sifat teknis dari massa batuan menjadi hal yang penting untuk diperhatikan. Sektor Lemajung merupakan salah satu area prospek untuk penambangan uranium di Kalan, Kalimantan Barat. Tujuan penelitian adalah mendapatkan data karakteristik massa batuan yang merupakan data dasar bagi perencanaan pengembangan teknik penambangan cebakan bahan galian. Metodologi yang digunakan adalah dengan pengambilan contoh batuan untuk analisis laboratorium mekanika batuan, pengamatan rekahan, dan pengamatan kondisi airtanah. Parameter batuan yang dianalisis meliputi uniaxial compressive strength (UCS), rock quality designation (RQD), jarak rekahan, kondisi rekahan, dan airtanah. Hasil analisis menyimpulkan bahwa metalanau sebagai litologi yang mengandung uranium di Sektor Lemajung mempunyai nilai rock mass rating (RMR) sebesar 56 atau kelas massa batuan III: fair rock pada kedalaman sekitar 60 m, dan pada kedalaman 280 m nilai RMR mencapai 82 atau kelas massa batuan I: very good rock. Data nilai RMR tersebut selanjutnya dapat digunakan dalam analisis pembuatan terowongan pada model tambang bawah tanah atau analisis kestabilan lereng pada model tambang terbuka. Rock mass characterization is required in design of rock opening, which calculation of engineering characters of rock mass become one important parameter toconsider. Lemajung sector is one of prospect area for uranium mining in Kalan, West Kalimantan. Purpose of research is to acquire rock mass characteristicsas basic data for planning the development of mining technique of ore deposit. Methodology applied is rock sampling for rock mechanic laboratory analysis, observation of joints, and observation of groundwater condition. Rock parameters analyzed includes uniaxial compressive strength (UCS), rock quality designation (RQD), joint spacing, joint condition, and groundwater. Analysis concluded that metasiltstonewhich is lithology contained uranium in Lemajung Sector has rock mass rating (RMR) value of 56 or rock mass class III: fair rock in the depth of around 60 m, and in the depth of 280 m RMR value reach 82 or rock mass class I: very good rock. RMR value data furthermore could be used for analysis of tunneling in the model of underground mine or slope stability analysis in the model of open pit mine.
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Shaorui, Sun, Lu Yexu, Xu Yuanyuan, Liu Jin, and Wei Jihong. "Study on Analog Theory of Rock Mass Simulation and Its Engineering Application." Mathematical Problems in Engineering 2013 (2013): 1–11. http://dx.doi.org/10.1155/2013/491069.
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During construction of 3D geological models, it is difficult to determine the uniform between geological model and true model. As a comprehensive index, rock quality designation (RQD) is reliable to assess the rationality of geological models. Unfortunately, The RQD of rockmass is determined completely by the deterministic threshold value and directions of the scan lines presently. To avoid this drawback, the modified method of the RQD value based on the threshold value and 3D space is proposed in this paper. Simultaneously, the analogue-simulation method based on rupture mechanism and classification of discontinuities is proposed. The elliptical discontinuity is considered for general discontinuity, and the special discontinuities, such as bedding, fault, and interlayer are dealt with individually. The accuracy of the 3D model is verified by the modified RQD. The 3D model of the rockmass is analogue simulated through repetitively obtaining data from the interval confidence of geometrical parameters of discontinuities, which are determined by a mass of data derived from field investigation. Besides, the dam base of the Xiangjiaba hydropower station is taken as an example, and the 3D model of the dam base is analog-simulated; its stability is evaluated by DDA method. The safety coefficient of the dam base is obtained by utilizing the overload method.
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Duda, Robert. "Methods of Determining Rock Mass Freezing Depth for Shaft Sinking in Difficult Hydrogeological and Geotechnical Conditions/Określenie Głębokości Zamrażania Górotworu Dla Potrzeb Głębienia Szybów W Trudnych Warunkach Hydrogeologicznych I Geotechnicznych." Archives of Mining Sciences 59, no. 2 (June 1, 2014): 517–28. http://dx.doi.org/10.2478/amsc-2014-0038.
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Abstract Methods of determining the depth of rock mass freezing for the purpose of shaft sinking in solid rocks in difficult hydrogeological and geomechanical conditions are analyzed in this paper. There are presented factors on the basis of which the freezing depth can be determined in heterogeneous rocks media. The author focuses on the source of problems with establishing parameters used for defining the freezing depth. A method of interpreting hydrogeological and geomechanical source data is presented on two examples of weak and medium compact sandstones freezing for the purpose of shaft sinking in the Legnica-Głogów Copper Mining District, south-western Poland. Moreover, a general algorithm for determining the rock mass freezing depth is given. The following main criteria of freezing depth evaluation have been assumed: hydraulic conductivity values, porosity, rock quality designation index (RQD) and Protodiakonow’s rock compaction index. The outflow of drilling fluid in the exploration borehole was taken into account as a complementary criterion. The practical use of the algorithm was exemplified by a geological profile.
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Singh, Jaya Laxmi, and Naresh Kazi Tamrakar. "Rock Mass Rating and Geological Strength Index of rock masses of Thopal-Malekhu River areas, Central Nepal Lesser Himalaya." Bulletin of the Department of Geology 16 (October 11, 2013): 29–42. http://dx.doi.org/10.3126/bdg.v16i0.8882.
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The rock slopes of the Thopal-Malekhu River areas, Lesser Himalaya, were characterized applying various systems of rock mass classification, such as Rock mass Rating (RMR) and Geological Strength Index (GSI), because the study area comprises well exposed rock formations of the Nawakot and Kathmandu Complexes, across the Thopal-Malekhu River areas. In RMR system, mainly five parameters viz. Uniaxial Compressive Strength (UCS) of rock, Rock Quality Designation (RQD), spacing of discontinuity, condition of discontinuity, and groundwater condition were considered. The new GSI charts, which were suitable for schistose and much disintegrated rock masses, were used to characterize rock slopes based on quantitative analysis of the rock mass structure and surface condition of discontinuities. RMR ranged from 36 to 82 (poor to very good rock mass) and GSI from 13.5±3 to 58±3 (poor to good rock mass). Slates (of the Benighat Slate) are poor rock masses with low strength, very poor RQD, and close to very close spacing of discontinuity, and dolomites (Dhading Dolomite) are fair rocks with disintegrated, poorly interlocked, and heavily broken rock masses yielding very low RMR and GSI values. Phyllites (Dandagaun Phyllite), schist (Robang Formation) and quartzite (Fagfog Quartzite, Robang Formation and Chisapani Quartzite), dolomite (Malekhu Limestone), and metasandstone (Tistung Formation) are fair rock masses with moderate GSI and RMR values, whereas quartzose schist and gneiss (Kulekhani Formation) are very good rock masses having comparatively higher RMR and GSI. The relationship between GSI and RMR shows positive and good degree of correlation. DOI: http://dx.doi.org/10.3126/bdg.v16i0.8882 Bulletin of the Department of Geology Vol. 16, 2013, pp. 29-42
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Choi, S. Y., and H. D. Park. "Variation of rock quality designation (RQD) with scanline orientation and length: a case study in Korea." International Journal of Rock Mechanics and Mining Sciences 41, no. 2 (February 2004): 207–21. http://dx.doi.org/10.1016/s1365-1609(03)00091-1.
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Pells, P. J., and S. E. Pells. "Reply to the discussion by Koutsoftas on “Rock quality designation (RQD): time to rest in peace”." Canadian Geotechnical Journal 55, no. 4 (April 2018): 593. http://dx.doi.org/10.1139/cgj-2017-0550.
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Adjiski, Vancho. "METHODOLOGY FOR AUTOMATED APPROACH IN DETERMINING THE ROCK QUALITY DESIGNATION (RQD) INDEX FROM DRILL CORE PHOTOGRAPHS." Природни ресурси и технологии 15, no. 1 (2021): 27–36. http://dx.doi.org/10.46763/nrt211510027a.
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Roslee, Rodeano, Jeffery Anak Pirah, Mohd Fauzi Zikiri, and Ahmad Nazrul Madri. "APPLICABILITY OF THE ROCK MASS RATING (RMR) SYSTEM FOR THE TRUSMADI FORMATION AT SABAH, MALAYSIA." Malaysian Journal of Geosciences 4, no. 2 (November 18, 2020): 96–102. http://dx.doi.org/10.26480/mjg.02.2020.96.102.
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Rock Mass Classification Systems (RMCS) can be of considerable use in the initial stage of a project when little or no detailed information is available. There is a large number of RMCS developed for general purposes but also for specific applications such as Rock Quality Designation (RQD), Rock Mass Rating (RMR), Rock Structure Rating (RSR), Geological Strength Index (GSI), Slope Mass Rating (SMR), etc. In this paper, we present the results of the applicability of the Rock Mass Rating (RMR) System for the Trusmadi Formation in Sabah, Malaysia. The RMR system is a RMCS incorporated with five (5) parameters: Strength of intact rock material, Rock Quality Designation (RQD), Spacing of joints, Condition of joints, and Groundwater conditions. A total of ten (10) locations were selected on the basis of exposures of the lithology and slope condition of the Trusmadi Formation. Trusmadi Formation is Paleocene to Eocene in aged. The Trusmadi Formation generally shows two major structural orientations NW-SE and NE-SW. Trusmadi Formation is characterized by the present of dark colour argillaceous rocks, siltstone and thin-bedded turbidite in well-stratified sequence. Some of the Trusmadi Formation rocks have been metamorphosed to low grade of the greenish-schist facies; the sediment has become slate, phyllite and metarenite. Cataclastic rocks are widespread and occur as black phyllonite enclosing arenitic and lutitic boudins with diameter up to a meter or demarcating thin to thicker fault zones or as flaser zones with hardly any finer grain matrix or as zones of closely spaced fractures. Quartz and calcite veins are quite widespread within the crack deformed on sandstone beds. The shale is dark grey when fresh but changes light grey to brownish when weathered. The RMR system for 10 outcrops ranges from 33.0 to 50.0 and its classified as “Fair” (Class III) to “Poor” (Class IV) rocks. The Fair Rock (Class III) recommended that the excavation should be top heading and bench 1.5 m – 3 m advance in the top heading. Support should be commencing after each blast and complete support 10 m from face. Rock bolts should be systematic with 4 m long spaced 1.5 m – 2 m in crown and walls with wire mesh in crown. Shotcrete should be 50 mm – 100 mm in crown and 30 mm in sides. While for the Poor Rock (Class IV), the excavation should be top heading and bench 1.0 m – 1.5 m advance in top heading. Support should be installed concurrently with excavation, 10 m from face. Rock bolt should be systematic with 4 m – 5 m long, spaced 1.5 m – 1.5 m in crown and walls with wire mesh. Shotcrete of 100 m – 150 mm in crown and 100 mm in sides. The steel sets should be light to medium ribs spaced 1.5 m only when required.
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Yasrebi, A. B., A. Hezarkhani, P. Afzal, and N. Madani. "Application of an Inverse Distance Weighted Anisotropic Method for Rock Quality Designation distribution in Eastern Kahang deposit, Central Iran." Journal of Mining and Metallurgy A: Mining 55, no. 1 (2019): 1–15. http://dx.doi.org/10.5937/jmma1901001y.
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Sánchez, L. Katherine, Xavier Emery, and Serge A. Séguret. "Geostatistical modeling of Rock Quality Designation (RQD) and geotechnical zoning accounting for directional dependence and scale effect." Engineering Geology 293 (November 2021): 106338. http://dx.doi.org/10.1016/j.enggeo.2021.106338.
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Syam, Muhammad Amin, Tommy Trides, and Heryanto Heryanto. "ANALISIS KESTABILAN LERENG BEDASARKAN NILAI SLOPE MASS RATING DI DESA SUKAMAJU, TENGGARONG SEBERANG, KUTAI KARTANEGARA, KALIMANTAN TIMUR." JURNAL GEOCELEBES 2, no. 2 (October 22, 2018): 53. http://dx.doi.org/10.20956/geocelebes.v2i2.5158.
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Penelitian ini dilakukan untuk menganalisis kestabilan lereng berdasarkan nilai Slope Mass Rating lereng batuan pada desa Sukamaju, Tenggarong Seberang, Kutai Kartanegara. Slope Mass Rating adalah sistem klasifikasi massa batuan yang dirancang khusus untuk lereng batuan dengan menggabungkan nilai Rock Mass Rating dan penyesuaian terhadap arah orientasi kekar. Parameter yang digunakan dalam metode ini adalah nilai kuat tekan, Rock Quality Designation (RQD), spasi bidang kekar, kondisi bidang kekar, dan kondisi airtanah. Nilai kuat tekan batuan pembentuk lereng adalah 27.14 Mpa dengan bobot 4, nilai RQD sebesar 85% dengan bobot 17, spasi kekar rata-rata 48 cm dengan bobot 10, kondisi kekar dengan bobot 20, kondisi airtanah dengan bobot 15, arah orientasi lereng tidak menguntungkan dengan bobot -24, dan lereng masih merupakan lereng alamiah sehingga tidak ada aktifitas akan dieskavasi denan bobot 15. Dengan menjumlahkan setiap parameter, maka diperoleh nilai Slope Mass Rating (SMR) sebesar 57. Nilai ini bermakna bahwa kondisi batuan tergolong lereng dengan kualitas massa batuan yang normal, stabil pada sebagian lereng, dan dapat terjadi longsoran berupa jatuhan batuan dari kekar dan longsoran baji.
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Zheng, Jun, Xiaojuan Yang, Qing Lü, Yu Zhao, Jianhui Deng, and Zhenjie Ding. "A new perspective for the directivity of Rock Quality Designation (RQD) and an anisotropy index of jointing degree for rock masses." Engineering Geology 240 (June 2018): 81–94. http://dx.doi.org/10.1016/j.enggeo.2018.04.013.
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Yan, Xiao Ming, Xiang Yun Chen, and Feng Qiang Gong. "Instability Identification of Goaf Risky in Mines Based on Distance Discriminant Analysis Method." Advanced Materials Research 255-260 (May 2011): 3740–43. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.3740.
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The instability identification of goaf risky is an important work in the mine engineering. Based on distance discriminant analysis, a method to identify the instability of goaf risky in mines was presented in this paper. Nine factors influencing the stability of goaf risky, including uniaxial compressive strength of rock, elastic modulus of rock, rock quality designation (RQD), area ration of pillar, ratio of width to height of pillar, depth of ore body, volume of goaf, dip of ore body and area of goaf, were selected as discriminant indexes in the stability analysis of goaf. The actual data of 40 goafs were used as training samples to establish a discriminant analysis model to identify the stability of goaf. The results show that this discriminant analysis model has high precision and misdiscriminant ratio is 0.025 in re-substitution process. The instability identification of a metal mine was discriminanted by using this model and the identification result is identical with that of practical situation.
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Aalizad, Seyed Ali, and Farshad Rashidinejad. "Prediction of penetration rate of rotary-percussive drilling using artificial neural networks – a case study / Prognozowanie postępu wiercenia przy użyciu wiertła udarowo-obrotowego przy wykorzystaniu sztucznych sieci neuronowych – studium przypadku." Archives of Mining Sciences 57, no. 3 (December 1, 2012): 715–28. http://dx.doi.org/10.2478/v10267-012-0046-x.
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Abstract Penetration rate in rocks is one of the most important parameters of determination of drilling economics. Total drilling costs can be determined by predicting the penetration rate and utilized for mine planning. The factors which affect penetration rate are exceedingly numerous and certainly are not completely understood. For the prediction of penetration rate in rotary-percussive drilling, four types of rocks in Sangan mine have been chosen. Sangan is situated in Khorasan-Razavi province in Northeastern Iran. The selected parameters affect penetration rate is divided in three categories: rock properties, drilling condition and drilling pattern. The rock properties are: density, rock quality designation (RQD), uni-axial compressive strength, Brazilian tensile strength, porosity, Mohs hardness, Young modulus, P-wave velocity. Drilling condition parameters are: percussion, rotation, feed (thrust load) and flushing pressure; and parameters for drilling pattern are: blasthole diameter and length. Rock properties were determined in the laboratory, and drilling condition and drilling pattern were determined in the field. For create a correlation between penetration rate and rock properties, drilling condition and drilling pattern, artificial neural networks (ANN) were used. For this purpose, 102 blastholes were observed and drilling condition, drilling pattern and time of drilling in each blasthole were recorded. To obtain a correlation between this data and prediction of penetration rate, MATLAB software was used. To train the pattern of ANN, 77 data has been used and 25 of them found for testing the pattern. Performance of ANN models was assessed through the root mean square error (RMSE) and correlation coefficient (R2). For optimized model (14-14-10-1) RMSE and R2 is 0.1865 and 86%, respectively, and its sensitivity analysis showed that there is a strong correlation between penetration rate and RQD, rotation and blasthole diameter. High correlation coefficient and low root mean square error of these models showed that the ANN is a suitable tool for penetration rate prediction.
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Liu, Yang, Yicheng Ye, Qihu Wang, and Xiaoyun Liu. "Stability Prediction Model of Roadway Surrounding Rock Based on Concept Lattice Reduction and a Symmetric Alpha Stable Distribution Probability Neural Network." Applied Sciences 8, no. 11 (November 5, 2018): 2164. http://dx.doi.org/10.3390/app8112164.
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To combat the uncertainty of the multiple factors affecting roadway surrounding rock stability, five initial indexes are selected for reduction according to concept lattice theory: rock quality designation (RQD), uniaxial compressive strength (Rc), the integrity coefficient of rock mass, groundwater seepage, and joint condition. The aim of this study is to compute correlation coefficients among various indexes and verify the effectiveness of lattice reduction. Alpha stable distribution is used to replace the commonly used Gauss distribution in probabilistic neural networks. A prediction model for the stability of roadway surrounding rock is then established based on a concept lattice and improved probabilistic neural network. 100 groups of training sample data are plugged into this model one by one to examine its rationality. The established model is employed for engineering application prediction with ten indiscriminate sample groups from the Jianlinshan mining area of the Daye iron mine, revealing accuracy of up to 90%. This demonstrates that our prediction model based on a concept lattice and improved probabilistic neural network has high reliability and applicability.
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Aprilliana, Taufik Toha, and Budhi Kuswan Susilo. "GEOMETRI PELEDAKAN BERDASARKAN ROCK MASS RATING (RMR) DAN FRAGMENTASI HASIL PELEDAKAN." Jurnal Pertambangan 4, no. 4 (November 1, 2020): 209–15. http://dx.doi.org/10.36706/jp.v4i4.620.
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Peledakan merupakan salah satu metode pembongkaran lapisan batuan. Hasil dari peledakan ini adalah fragmentasi batuan yang berukuran beragam. Salah satu faktor yang mempengaruhi ukuran fragmentasi ini sangat dipengaruhi oleh geometri peledakan. Geometri peledakan sulit untuk dievaluasi karena belum pernah melakukan analisis fragmentasi hasil peledakan menggunakan software. Tujuan dari penelitian ini adalah mengevaluasi geometri peledakan, Identifikasi kelas massa batuan menggunakan Rock Mass Rating (RMR), dan menganalisis fragmentasi hasil peledakan. Metode identifikasi kelas massa batuan dalam penelitian ini menggunakan metode rock mass rating (RMR) meliputi kuat tekan batuan, rock quality designation (RQD), jarak diskontinuity, kondisi diskontinuity, dan air tanah. Sedangkan fragmentasi hasil peledakan dianalisis menggunakan software split desktop. Pada analisis ini foto fragmentasi hasil peledakan di front dan di disposal diambil langsung sebagai data utama yang menjadi dasar dari analisis ini. Berdasarkan hasil analisis RMR diketahui bahwa batuan yang dibongkar adalah jenis claystone dengan rating kuat tekan 1, RQD 8, Jarak diskontinuitas 15, kondisi diskontinuitas 0, kondisi air tanah 15. Jadi total rating RMR 39 yang berarti batuan ini tergolong batuan jelek atau lunak. data diketahui bahwa batuan yang diledakkan merupakan jenis claystone kelas IV yang berarti jelek atau lunak, Hasil analisis fragmentasi hasil peledakan di disposal lebih kecil dan seragam dibandingkan dengan fragmentasi di front, perbedaan ukuran fragmentasi ini akibat adanya pengaruh dari aktivitas gali muat dan angkut material dari front ke disposal. Produktivitas excavator sudah sesuai dengan buku panduan yang berarti fragmentasi hasil peledakan sudah baik sehingga geometri peledakan tidak perlu diperbaiki.
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Zheng, Jun, Xiaohong Wang, Qing Lü, Jianfeng Liu, Jichao Guo, Tiexin Liu, and Jianhui Deng. "A Contribution to Relationship Between Volumetric Joint Count (Jv) and Rock Quality Designation (RQD) in Three-Dimensional (3-D) Space." Rock Mechanics and Rock Engineering 53, no. 3 (October 22, 2019): 1485–94. http://dx.doi.org/10.1007/s00603-019-01986-3.
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Dimitrov, Ivan. "Structural geological methods in the geotechnical practice – rock mass rating. Advantages and problems of the rating methods." Review of the Bulgarian Geological Society 81, no. 1 (2020): 35–54. http://dx.doi.org/10.52215/rev.bgs.2020.81.1.3.
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This paper presents a review of the most common geotechnical rock rating methods. The directional properties of the rock’s anisotropies are exemplified, by a case of resolution of stresses in folded and foliated metamorphic rocks. In such rocks, depending on the geometry of the folds, the ambient stress field can generate varying shear potential along the foliation planes in different parts of the excavation. The commonly used rating schemes, with accent on the geological feasibility of the classifications, are discussed – Protodiakonov’s rock scale, Terzaghi’s grading for construction of tunnels, then the rock quality designation of Deere, the Bieniawski’s rock mass rating (RMR), the Hoek, and Brown’s GSI and the Barton’s Q-system. It is emphasized that in spite of its broad use, the RQD is distorting the statistical weight of the joint groups as some steeply dipping joints may be completely neglected. It is recognized that the RMR is the simplest to use but underestimates the directional properties of the rock anisotropies, which require better definition and has no provision for lithologically varying rock packages, although it has the advantage of using the uniaxial compressive strength, which other systems do not employ. The Hoek and Brown’s criterion went too far with complex empirical relationships, which rely on extensive laboratory testing, so it is no more field criterion. Besides, its geological descriptive powers are rather poor and now, new form of GSI classification is offered for nearly every lithological type. Barton’s Q-system, being best suited to case studies of actual underground constructions, suffers from the fact that is centered nearly exclusively on joints, which may be justified in Norway, where mainly magmatic and high grade metamorphic rocks are present but should be applied cautiously in areas, where sedimentary, volcanic and strongly foliated rocks are exposed. In general, for all the discussed geomechanical classification systems (RMR, GSI, Q) the rule is valid, that they work better in an isotropic, strong but jointed rock masses and do not work well in week layered and foliated rocks.
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Hawkins, A. B. "Rock Descriptions." Geological Society, London, Engineering Geology Special Publications 2, no. 1 (1986): 59–66. http://dx.doi.org/10.1144/gsl.1986.002.01.13.
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AbstractThe paper critically reviews the description and classification of rocks for engineering purposes given in BS 5930. It makes a number of recommendations. These are concerned principally with the naming of carbonate rocks, weathering terms, the use of saturated strengths, correlation factors for use with point load strengths, the use of solid core rather than axial core measurements for ROD and not using a legend when the core recovery is less than 80%. The paper introduces the concept of an RQD300 and proposes the use of a lithological quality designation (LQD100 and LQD300). A change is suggested in the descriptive word order.
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Sui, Haoyue, Wei Gao, and Ruilin Hu. "A New Evaluation Method for the Fracability of a Shale Reservoir Based on the Structural Properties." Geofluids 2019 (December 4, 2019): 1–14. http://dx.doi.org/10.1155/2019/2079458.
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The fracability of shale reservoirs is one of the key indicators used for evaluating whether or not the shale can be used as a “sweet spot zone.” It has been determined that the structural properties of rock have important influences on the evaluation of the fracability of reservoirs. In the current study, five rock quality designation (RQD) calculation methods were compared and analyzed for the purpose of selecting an RQDI for characterizing rock structures. Focused on the lack of structural factors included in the previous fracability evaluation methods, a new model for fracability evaluation based on the combination of the brittleness index, structural index, and fracture toughness was constructed using a linear elastic fracture theory. The model showed that good fracability not only included higher brittleness but also required less energy to produce cracks. Meanwhile, good fracability also required more discontinuous structural planes. In the current study, a formation with a higher fracability index was considered to be a fractureable interval and a formation with a lower fracability index was a fracture barrier. Finally, the reservoir fracability index was modeled using the Xike 2 well in the north of Guizhou Province as a case study. Subsequently, a fracability logging evaluation method based on the fracability index model was determined, which will potentially provide a new technical tool for future fracturing optimization processes.
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Albarelli, D. S. N. A., O. C. Mavrouli, and P. Nyktas. "Identification of potential rockfall sources using UAV-derived point cloud." Bulletin of Engineering Geology and the Environment 80, no. 8 (June 5, 2021): 6539–61. http://dx.doi.org/10.1007/s10064-021-02306-2.
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AbstractRecent advances in remote sensing techniques and computer algorithms allow accurate, abundant, and high-resolution geometric information retrieval for rock mass characterization from 3D point clouds. The automatic application of the extracted information for local scale rockfall susceptibility assessment, where discontinuities characteristics play a major role in rocky slope stability, requires step by step logical procedures. This paper presents a novel methodology to use the extracted discontinuity set characteristics for a local scale rockfall susceptibility assessment, tailored for Uncrewed Aerial Vehicle (UAV) data acquisition. The method consists of 4 steps: (i) 3D slope model reconstruction using UAV digital photogrammetry, (ii) automatic characterization of discontinuity sets, (iii) slope stability analysis, and (iv) susceptibility assessment using a new Rockfall Susceptibility Index. The proposed method was applied to a road cut rocky slope in a mountainous area of the Samaria National Park, in Crete Island, Greece. Visual validation indicates that the areas of higher and moderate rockfall susceptibility on the 3D model of the rocky slope are adjacent to rockfall source areas marked by the presence of fallen blocks on the foot of the slope. The proposed methodological workflow presents novelties related to the use of point clouds for the estimation of the Rock Quality Designation (RQD) index, the visualization of discontinuity set spacing, the evaluation of the persistence and the Slope Mass Rating (SMR) index, as well as the incorporation of the persistence of overhangs into the rockfall susceptibility assessment and visualization.
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Milus, Archan, Eko Santoso, and Hafidz Noor Fikri. "Kajian pengaruh faktor batuan terhadap fragmentasi batuan overburden hasil peledakan berdasarkan model Kuz-Ram." Jurnal Himasapta 6, no. 2 (August 31, 2021): 79. http://dx.doi.org/10.20527/jhs.v6i2.3963.
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Distribusi fragmentasi hasil peledakan dipengaruhi oleh beberapa faktor ialah massa batuan, jenis bahan peledak, jumlah bahan peledak yang digunakan, deskripsi massa batuan didalam faktor batuan pada daerah penelitian yaitu powdery dan blocky. Penelitian ini berfokus pada pengaruh factor batuan terhadap fragmentasi hasil peledakan overburden.Metode yang digunakan pada penelitian ini adalah pengamatan secara langsung dilapangan untuk mendapatkan gambaran mengenai kondisi situasi aktual seperti keterdapatan rock mass description (RMD), joint plane spacing (JPS), joint plane orientation (JPO), specific gravity (SGI), hardness. Pada penelitian faktor batuan hanya nilai RQD yang memiliki pengaruh sangat besar dalam peledakan. Analisis faktor batuan terhadap fragmentasi batuan menggunakan perangkat lunak Split Desktop 2.0 untuk menghitung hasil fragmentasi aktual hasil peledakan sedangkan untuk teoritis menggunakan metode model Kuz-Ram. Berdasarkan kajian nilai rock quality designation terhadap fragmentasi batuan hasil peledakan didapatkan nilai fragmentasi 80 cm ≥ 80% dikatakan ideal, hasil fragmentasi pada 2 lokasi penelitian dengan kegiatan peledakan 6 kali ialah 93,61%, 87,68%, 90,91% (powdery) dan 72,68%, 74.56%, 76.04% (blocky) untuk perhitungan model Kuz-Ram. Jadi pada satu lokasi penelitian masih di jumpai hasil distribusi fragmentasi yang kurang bagus dengan ukuran saringan 80 cm ≤ 80%, yaitu pada deskripsi massa batuan blocky. Kata Kunci: factor batuan, fragmentasi batuan, hasil peledakan, massa batuan
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Kayabasi, Ali, and Candan Gokceoglu. "An Assessment on Permeability and Grout Take of Limestone: A Case Study at Mut Dam, Karaman, Turkey." Water 11, no. 12 (December 15, 2019): 2649. http://dx.doi.org/10.3390/w11122649.
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The main purposes of the present study are to evaluate pilot grouting and to develop regression equations for prediction of grout intake. There are no permeability problems with the sandstone-siltstone-claystone alternations and basement clayey limestone at the dam site. Karstic limestone block is permeable due to karstification and heavy discontinuities. For the purpose of the study, Q system, geological strength index (GSI), secondary permeability index (SPI), joint spacing (JSP), joint apertures (Ap), Lugeon (Lu), and the permeability coefficient (k) were determined. Karstic limestone block rock mass properties correlated with grouting material amount. A series of simple and multiple nonlinear regression analyses was performed between grout take material amount (Gt) and average values of these rock mass properties. Significant determination coefficients were determined. Prediction capacity of the empirical equations were also examined with root mean square error (RMSE), values account for (VAF), mean absolute percentage error (MAPE), and prediction error evaluations. Considering simple regression analyses, the equation derived with Gt-SPI gives the best performance. The best prediction is determined with the equation derived with rock quality designation values (RQD), SPI, and joint aperture as input parameters with the multiple nonlinear regression analysis, in addition to this, other empirical equations also provide acceptable results.
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Assari, Amin, and Zargham Mohammadi. "Analysis of rock quality designation (RQD) and Lugeon values in a karstic formation using the sequential indicator simulation approach, Karun IV Dam site, Iran." Bulletin of Engineering Geology and the Environment 76, no. 2 (May 24, 2016): 771–82. http://dx.doi.org/10.1007/s10064-016-0898-y.
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Jumaidi, Jumaidi, Munirwansyah Munirwansyah, and Sofyan M. Saleh. "KUAT TARIK ANGKER KANTILEVER DENGAN METODE PENDEKATAN JRC (STUDI KASUS JALAN KANTILEVER KM. 461+480 TAPAKTUAN)." Jurnal Teknik Sipil 1, no. 3 (January 15, 2018): 647–56. http://dx.doi.org/10.24815/jts.v1i3.10010.
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Abstract: The Tapaktuan-Bakongan is the national road access to the South-West part of Aceh. Topographically shows that the road consist of canyon and a very steep cliff, which will be impossible to build more infracstructure using either blasting or cut and fill method with heavy equipment. Referring to the situation, the study about anchor tensile strength, which is used in construction of road access expansion using cantilever method is conducted. The research methode is begin by collecting the real data which are Standard Penetration Test data (SPT) SNI 4153-2018 and tensile graund anchor proving test (Bristish Satndard 8081:1981) and geological data taken from SPT drilling data. Furthermore, the data involved N-SPT, Joint Roughness Coefficient (JRC), shear stress will be analyzed and yield loading test value. Finally, from the loading test value, the reseacher will evaluate the stability of tensile capacity and safety factor (SF) of ground anchor. From the data analysis obtained that rock mass of STA 1+ 280 or KM. 461 +480 geologically contain unrigid and very strong limestone with N-SPT value greater than 50 where the rock condition is solid concrete and could be crushed using blasting method. Five samples are taken from the 10 meters driling for the laboratory test and obtain the minimum compressive strength is 51,10 MPa and maximum is 103,89 MPa with JRC from 2 to 20. In addition, the rock quality designation (RQD) calculation yield the average stone quality is 60,8% which means the rock has medium quality. Ground anchor failure if the proving test over 80% UTS(ultimate tensile strength) i.e. the load increment reaches 92,55% UTS or 54 MPa. Therefore, the proving test maximum capacity for ground anchor is 54 Mpa and safety factor is 1,85 which are suitable to geological condition research area.Abstrak: Ruas jalan Tapaktuan – Bakongan merupakan ruas jalan nasional lintas Barat – Selatan Aceh. Kondisi topografi ruas jalan terdiri dari tebing yang terjal dan lereng yang curam sehingga tidak memungkinkan dilaksanakan pelaksanaan kontruksi pembangunan/peningkatan dengan metode blasting (penggunaan bahan peledak) maupun metode cut and fill yang menggunakan alat-alat berat. Dari permasalahan tersebut dilakukan sebuah kajian mengenai kuat tarik angker yang digunakan pada pelaksanaan pembangunan pelebaran badan jalan dengan menggunakan metode kantilever untuk daerah dengan kondisi topograsi tebing yang terjal dan lereng yang curam. Metode yang diterapkan pada penelitian ini diawali dengan pengumpulan data riil yang meliputi data Standard Penetration Test (SPT) SNI 4153-2008 dan uji tarik proving test ground anchor (British Standard 8081:1981) dan data geologi yang dihasilkan dari data pengeboran SPT. Selanjutnya dari data-data yang diperoleh dilakukan analisis data yang meliputi analisis nilai N-SPT, Joint Roughnes Coefficient (JRC), gaya geser, yang menghasilkan angka loading test. Dari data hasil loading test dapat dievaluasi stabilitas kapasitas tarik dan safety factor (SF). Dari data analisis didapatkan bahwasanya kondisi geologi batuan di STA 1+ 280 atau KM. 461 + 480 terdiri dari batu gamping tidak lapuk dan sangat keras dan dapat dipecahkan dengan peledakan dengan nilai N-SPT lebih besar dari 50 dimana kondisi batuan sangat padat. Dari hasil pengeboran sepanjang 10 meter diambil lima sampel untuk di uji laboratorium dan diperoleh nilai compressive strength minimal 51,10 MPa dan maksimum 103,89 MPa dengan nilai JRC 2-20. Selain daripada itu hasil perhitungan rock quality designation (RQD) menunjukkan kualitas batuan pada lokasi kajian rata-rata 60,8% yang berarti kualitas batuannya adalah sedang. Ground anchor putus pada saat uji tarik proving test diatas pembebanan 80% UTS yaitu pembebanan sampai 92,55% UTS (ultimate tensile strength) atau sebesar 54 MPa. Dengan demikian kapasitas maksimum hasil uji tarik proving test ground anchor yaitu sebesar 54 MPa dengan faktor keamanan 1,85 sesuai dengan kondisi geologi daerah kajian.
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Harraden, Cassady L., Matthew J. Cracknell, James Lett, Ron F. Berry, Ronell Carey, and Anthony C. Harris. "Automated Core Logging Technology for Geotechnical Assessment: A Study on Core from the Cadia East Porphyry Deposit." Economic Geology 114, no. 8 (December 1, 2019): 1495–511. http://dx.doi.org/10.5382/econgeo.4649.
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Abstract The Cadia East porphyry deposit, located approximately 20 km south of Orange, New South Wales, Australia, contains a significant resource of copper and gold. This resource is hosted within the Forest Reefs Volcanics and is spatially and temporally associated with the Cadia Intrusive Complex. To extract ore, the underground mine currently uses the block cave mining method. The Cadia East geotechnical model provides data inputs into a range of numerical and empirical analysis methods that make up the foundation for mine design. These data provide input into the construction of stress models, caveability models, ground support design, and fragmentation analysis. This geotechnical model encompasses two commonly used rock classification systems that quantify ground conditions: (1) rock mass rating (RMR) and (2) rock tunneling quality index (Q index). The RMR and Q index are calculated from estimates of rock quality designation (RQD), number of fracture sets, fracture roughness, fracture alteration, and fracture spacing. Geologists and geotechnical engineers collect information used to produce these estimates by manually logging sections of drill core, a time-consuming task that can result in inconsistent data. Modern automated core scanning technologies offer opportunities to rapidly collect data from larger samples of drill core. These automated core logging systems generate large volumes of spatially and spectrally consistent data, including a model of the drill core surface from a laser profiling system. Core surface models are used to extract detailed measurements of fracture location, orientation, and roughness from oriented drill core. These data are combined with other morphological and mineralogical outputs from automated hyperspectral core logging systems to estimate RMR and the Q index systematically over contiguous drill core intervals. The goal of this study was to develop a proof-of-concept methodology that extracts geotechnical index parameters from hyperspectral and laser topographic data collected from oriented drill core. Hyperspectral data from the Cadia East mine were used in this case study to assess the methods. The results show that both morphological and mineralogical parameters that contribute to the RMR and Q index can be extracted from the automated core logging data. This approach provides an opportunity to capture consistent geologic, mineralogical, and geotechnical data at a scale that is too time-consuming to achieve via manual data collection.
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Roslee, Rodeano, Jeffery Anak Pirah, Ahmad Nazrul Madri, and Mohd Fauzi Zikiri. "APPLICABILITY OF THE GEOLOGICAL STRENGTH INDEX (GSI) CLASSIFICATION FOR THE TRUSMADI FORMATION AT SABAH, MALAYSIA." Earth Science Malaysia 4, no. 1 (November 18, 2020): 77–81. http://dx.doi.org/10.26480/esmy.01.2020.77.81.
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During the feasibility and preliminary design stages of a project, when very little detailed information on the rock mass and its geomechanic characteristics is not available, the use of a Rock Mass Classification Scheme (RMCS) can be of considerable benefit. Various parameters were used in order to identify the RMCS. The parameter comprised of Rock Quality Designation (RQD), Rock Mass Rating (RMR), Rock Structure Rating (RSR), Geological Strength Index (GSI), Slope Mass Rating (SMR), etc. In this paper, we present the results of the applicability of the Geological Strength Index (GSI) classification for the Trusmadi Formation in Sabah, Malaysia. The GSI classification system is based on the assumption that the rock mass contains a sufficient number of “randomly” oriented discontinuities such that it behaves as a homogeneous isotropic mass. In this study, the GSI relates the properties of the intact rock elements/blocks to those of the overall rock mass. It is based on an assessment of the lithology, structure and condition of discontinuity surfaces in the rock mass and is estimated from visual examination of the rock mass exposed in outcrops or surface excavations. A total of ten (10) locations were selected on the basis of exposures of the lithology and slope condition of the Trusmadi Formation. The Trusmadi Formation regionally experienced of two major structural orientations NW-SE and NE-SW. It consists mostly of dark grey shale with thin bedded sandstones, typical of a turbidite deposit. This unit has been subjected to low grade of metamorphism, producing slates, phyllites and meta-sediments and intense tectonic deformation producing disrupted or brecciated beds. Quartz vein are quite widespread within the joints on sandstone beds. The shale is dark grey when fresh but changes light grey to brownish when weathered. The results are classified as “Poor Rock” to “Fair Rock” in term of GSI. The poor categories (TR2 and TR7) represent slickensided, highly weathered surfaces with compact coatings or fillings or angular fragments. It is also characterized as blocky/ disturbed/seamy, which folded with angular blocks formed by many intersecting discontinuity sets. The fair categories can be divided into two (2) types; type 1 (TR1, TR6 and TR8) which represent as smooth, moderately weathered and have altered surfaces. It is also characterised as very blocky rock, which indicates interlocked, partially disturbed ass with multi-faceted angular blocks formed by 4 or more joint sets. Type 2 (TR3, TR4, TR5, TR9 and TR10) which represent as smooth, moderately weathered and have altered surfaces but characterized as blocky/disturbed/seamy, which folded with angular blocks formed by many intersecting discontinuity sets. It also has persistence of bedding planes or schistosity.
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Wang, Qiqing, Wenping Li, and Qiangqiang Liu. "Geological Composition and Structure of the Filling Zone and Its Water-Resisting Property Evaluation on the Top of Ordovician Limestone." Geofluids 2019 (April 14, 2019): 1–15. http://dx.doi.org/10.1155/2019/5140605.
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With the gradual increase in mining depth of coal fields in North China, the threat posed by karstic Ordovician limestone water to the safe stoping of mines is becoming increasingly prominent. Investigating the water-resisting property of the filling zone on the top of the Ordovician limestone provides the key to safe mining under pressure. This paper analyzed the formation process of the filling zone on the top of Ordovician limestone in North China, and by combining analysis results of several geological field investigations on Ordovician outcrops, the filling zone on the top of Ordovician limestone was divided into three water-resisting structures: (1) completely filled, (2) incompletely filled, and (3) nonfilled. Based on the lithological composition, logging curves, and the water inflow status of several field boreholes, various characteristics of these clay-filled zones were used to determine the mudstone content from top to bottom. Using the interbedded mudstone thickness ratio, relative argillaceous content, impermeable filling zone thickness, rock quality designation (RQD), and faulting as evaluation factors, this paper evaluated the water-resisting property of the filling zone in the study area based on feature-weighted fuzzy C-means clustering (WFCM) algorithm and determined the extent of each zone. The completely filled zone accounts for 46.9% of the total area, incompletely filled zone accounts for 23.9%, and the zone not filled with clay material accounts for 29.2%. As indicated by field investigations on the boreholes, the actual percent of each zone is similar to the theoretical results. The study results present a vital guide for Ordovician limestone water control in deep mining.
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Şen, Zekâi, and Elsayed A. Eissa. "Volumetric Rock Quality Designation." Journal of Geotechnical Engineering 117, no. 9 (September 1991): 1331–46. http://dx.doi.org/10.1061/(asce)0733-9410(1991)117:9(1331).
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Iswandaru, Iswandaru, Rully Nurhasan R., Made Astawa Rai, and Ridho K. Wattimena. "Probabilistic Of Slope Failure Grasberg Open Pit Mining PT Freeport Indonesia." PROMINE 7, no. 1 (June 28, 2019): 01–07. http://dx.doi.org/10.33019/promine.v7i1.1064.
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The stability of a slope in mining activities is highly influenced by geology, especially thenature of rocks and geological structures. Slope stability analysis will be faced with severalproblems in the uncertainty of rock properties and rock mass. Slope stability analysis usingprobabilistic methods offers a more systematic way of treating conditions of uncertainty andprovides other alternatives to the value factor approach to security regarding information onthe probability of a slope failure.Grasberg Open Mine rock type classification based ongeotechnical parameters or Geotechnical Rock Code (GTRCK) classifies rocks based onrock type, rock mechanical properties, hydrothermal alteration type, clay content and RockQuality Designation (RQD) to 46 types of GTRCK. The GTRCK type which has a low rockmass strength value is a change in intrusive rock minerals and a low RQD value such as alot of clay material is exposed in the Northeast and Southwest of the Grasberg Open PitMine.The overall slope probabilistic modeling of the Grasberg mine uses a cross section of220o (northwest) with the effect of a 0.02g seismic factor which is the maximum criterionaccording to the probability of slope failure received with the average FK 1.13 and PK 0%.
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Wu, Xiao Guang, Zhi Qiang Yang, Qian Gao, and Duo Heng Ba. "The Classification and Quality Evaluation of Rock-Mass Based on Limited Geological Information." Applied Mechanics and Materials 580-583 (July 2014): 870–74. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.870.
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This paper takes the No. 1 ore body of Jinchuan 3rd mining area as an example, obtains the corresponding relation of surrounding rock quality evaluation index and spatial location.Through RMR rock classification method , using Rockware modeling system and limited geological informations, the statistical analysis of RMR and RQD showed that the rock of No. 1 ore body belongs to III~V type. Its rock mass is between normal to unstable. Through Rockware modeling system, we established the 3D rock properties model of UCS, RQD and RMR, and found that in the 5 to 6 rows of east hanging wall exists rock not conducive to the block caving method which belongs to the type of V. Finally, Statistical analysis was made based on the numerical model of strata. We find that , basically ,the rock block has good cavability because it belongs to the IV type of rock masses. However when design blocks and manage drawing, we must pay particular attention to the III type of rock, which is of moderate stability, and the V type of rock, which is less stable. All of these make a useful exploration for the research of key technology in the field of the interior of the earth.
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Talukder, Mohammad Kamruzzaman, Philippe Rosset, and Luc Chouinard. "Reduction of Bias and Uncertainty in Regional Seismic Site Amplification Factors for Seismic Hazard and Risk Analysis." GeoHazards 2, no. 3 (September 3, 2021): 277–301. http://dx.doi.org/10.3390/geohazards2030015.
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Site amplification factors in National Building Codes are typically specified as a function of the average shear wave velocity over the first 30 m (Vs30) or site class (A, B, C, D and E) for defined ranges of Vs30 and/or ranges of depth to bedrock. However, a single set of amplification factors may not be representative of site conditions across the country, introducing a bias in seismic hazard and seismic risk analyses. This is exemplified by significant differences in geological settings between East and West coast locations in North America. Western sites are typically characterized by lower impedance contrasts between recent surface deposits and bedrock in comparison to Eastern sites. In North America, site amplification factors have been derived from a combination of field data on ground motions recorded during West Coast earthquakes and numerical models of site responses that are meant to be representative of a wide variety of soil profiles and ground motions. The bias on amplifications and their impact on seismic hazards is investigated for the Montreal area, which ranks second for seismic risks in Canada in terms of population and hazard (PGA of 0.25 g for a 2475 years return period). Representative soil profiles at several locations in Montreal are analyzed with 1-D site response models for natural and synthetic ground motions scaled between 0.1 to 0.5 g. Since bedrock depths are typically shallow (<30 m) across the island, bedrock shear wave velocities have a significant influence on the impedance contrast and amplifications. Bedrock shear wave velocity is usually very variable due to the differences in rock formations, level of weathering and fracturing. The level of this uncertainty is shown to be greatly decreased when rock quality designation (RQD) data, common information when bore hole data are logged, is available since it is highly correlated with both shear and compression wave velocities. The results are used to derive region-specific site amplification factors as a function of both Vs30 and site fundamental frequency and compared to those of the National Building Code of Canada (2015). The results of the study indicate that there are large uncertainties associated with these parameters due to variability in soil profiles, soil properties and input seismic ground motions. Average and confidence intervals for the mean and for predictions of amplification factors are calculated for each site class to quantify this uncertainty. Amplifications normalized relative to class C are obtained by accounting for the correlation between site class amplifications for given ground motions. Non-linearity in the analysis of equivalent linear 1-D site response is taken into account by introducing the non-linear G/Gmax and damping ratios curves. In this method, it is assumed that the shear strain compatible shear modulus and damping ratio values remains constant throughout the duration of the seismic excitation. This assumption is not fully applicable to a case when loose saturated soil profile undergo heavy shaking (PGA > 0.3 g). In this study, all simulations with input motion PGA >0.3 g have been performed by using the EL method instead of the NL method considering that cohesive soils (clay and silt) at Montreal sites are stiff and cohesionless soils (sand and gravel) are considerably dense. In addition, the field and laboratory data required to perform NL analyses are not currently available and may be investigated in future works.