Analisis Pengaruh Getaran Peledakan Terhadap Kestabilan Lereng Pada Tambang Batubara Pit Roto Selatan Site Kideco, Kecamatan Batu Sopang, Kabupaten Paser, Provinsi Kalimantan Timur

In PT. BUMA site, there are some landslide which affected by blasting activity. Blasting activity iscarried out to destroy overburden material. The purpose of this research is to know the type oflandslide, the coefficient value of vibration decay from Peak Particle Acceleration (PPA), rock masscondition constant value from Peak Particle Acceleration (PPA), the Peak Particle Acceleration (PPA)value and the maximum acceleration (amax) which is at a point of safe in South Roto Pit. The researchmethods which used are the window mapping method in several sections at South Roto Pit.Description of rock mass that includes type of rock, rock strength, degree of weathering, block shape,type and shape of discontinuity, discontinuity filler and roughness level of discontinuity. ThisDescription of rock mass use Geological Strength Index (GSI) classification as a parameter to knowthe mechanical properties of rock mass (cohesion and internal shear angle). The research area has atype of toppling failure with eastward avalanche. The value of coefficient of vibration decay from PPA(k) is 44,66. The rock mass condition constant (α) is 1,802. The safe value of PPA highwall slopesarea of B STA 1 value is 0,184 g and the maximum acceleration (amax) value is 0,12 g. Highwall slopesarea B STA 2 with PPA value is 0,0769 g and maximum acceleration (amax) value is 0,05 g. Highwallslopes area C5 STA 3 with PPA value is 0,153 g and the maximum acceleration (amax) value is 0,1 g.Highwall slopes area C5 STA 4 with PPA value is 0,0307 g and the maximum acceleration (amax) valueis 0,02 g. Overall slopes area with PPA value is 0,0307 g and maximum acceleration (amax) value is0,02 g.

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Engineering Geological Characteristics Based on Rock Mass Rating (RMR) and Geological Strength Index (GSI) in Jlantah Dam Intake Tunnel, Karanganyar District, Central Java Province

E3S Web of Conferences ◽

10.1051/e3sconf/202132508003 ◽

2021 ◽

Vol 325 ◽

pp. 08003

Author(s):

Doni Apriadi Putera ◽

Heru Hendrayana ◽

I Gde Budi Indrawan

Keyword(s):

Rock Mass ◽

Research Area ◽

Geological Mapping ◽

Geological Strength Index ◽

Rock Mass Rating ◽

Strength Index ◽

Tunnel Support ◽

Weak Rocks ◽

Rock Mass Characterization ◽

Central Java

This paper presents the results of a geological engineering investigation in the form of rock mass characterization at the Jlantah Dam Intake Tunnel. The study was carried out through technical geological mapping, core drill evaluation and supported by laboratory test data. The determination of rock mass classification at the research site has been carried out using the Rock Mass Rating (RMR) method, but it is necessary to use another method that is more suitable based on rock mass for weak rocks, namely using the Geological Strength Index (GSI) method.The rock mass quality will be used as a parameter in determining the excavation method and tunnel support system that will be used in the Jlantah Dam intake tunnel. The results showed that the research area consisted of lithology in volcanic breccias and tuff lapilli. GSI rock mass value at the research location ranged from 15 - 65, while the RMR value ranged from 24 - 70. The correlation between RMR and GSI in the study area is different when compared to Hoek and Brown (1997) but has similarities with Zhang et al (2019).

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Study of Rock Mass Rating (RMR) and Geological Strength Index (GSI) Correlations in Granite, Siltstone, Sandstone and Quartzite Rock Masses

Applied Sciences ◽

10.3390/app11083351 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3351

Author(s):

Gabor Somodi ◽

Neil Bar ◽

László Kovács ◽

Marco Arrieta ◽

Ákos Török ◽

...

Keyword(s):

Rock Mass ◽

Linear Equations ◽

Geological Strength Index ◽

Gold Mine ◽

Strength Index ◽

Comprehensive Understanding ◽

Rock Types ◽

Mass Classification ◽

Waste Repository ◽

And Performance

A comprehensive understanding of geological, structural geological, hydrogeological and geotechnical features of the host rock are essential for the design and performance evaluation of surface and underground excavations. The Hungarian National Radioactive Waste Repository (NRWR) at Bátaapáti is constructed in a fractured granitic formation, and Telfer Gold Mine in Australia is excavated in stratified siltstones, sandstones and quartzites. This study highlights relationships between GSI chart ratings and calculated GSI values based on RMR rock mass classification data. The paper presents linear equations for estimating GSI from measured RMR89 values. Correlations between a and b constants were analyzed for different rock types, at surface and subsurface settings.

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Influence of the groundwater level on the bearing capacity of shallow foundations on the rock mass

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-021-02368-2 ◽

2021 ◽

Author(s):

Ana Alencar ◽

Rubén Galindo ◽

Svetlana Melentijevic

Keyword(s):

Rock Mass ◽

Bearing Capacity ◽

Groundwater Level ◽

Sensitivity Study ◽

Shallow Foundations ◽

Unit Weight ◽

Geological Strength Index ◽

Strength Index ◽

Mass Type

AbstractThe presence of the groundwater level (GWL) at the rock mass may significantly affect the mechanical behavior, and consequently the bearing capacity. The water particularly modifies two aspects that influence the bearing capacity: the submerged unit weight and the overall geotechnical quality of the rock mass, because water circulation tends to clean and open the joints. This paper is a study of the influence groundwater level has on the ultimate bearing capacity of shallow foundations on the rock mass. The calculations were developed using the finite difference method. The numerical results included three possible locations of groundwater level: at the foundation level, at a depth equal to a quarter of the footing width from the foundation level, and inexistent location. The analysis was based on a sensitivity study with four parameters: foundation width, rock mass type (mi), uniaxial compressive strength, and geological strength index. Included in the analysis was the influence of the self-weight of the material on the bearing capacity and the critical depth where the GWL no longer affected the bearing capacity. Finally, a simple approximation of the solution estimated in this study is suggested for practical purposes.

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