STABILITY ASSESSMENT OF ROCK SLOPES FROM RANAU, SABAH USING MODIFIED D-SLOPE METHOD
Journal Title: Geological Behavior (GBR) - Year 2018, Vol 2, Issue 2
Abstract
An assessment of stability potential of rock slopes from Ranau, Sabah has been conducted using modified D-slope method. D-slope comprises of G-Rating determination and Potential Instability to assess the slope condition using field observations, laboratory analysis and microfabric analysis. 17 parameters have been done for G-Rating purpose including the type of rocks, weathering grade, existence of faults and joints, number of major sets, number of orientations, aperture, persistence and spacing of discontinuities, rainfall, hydraulic condition, height of slope, history of instability, porosity, strength, micro-petrographic and micro-fractures index. Kinematic analysis is used for Potential Instability analysis to determine the type of failures for each slope. This later is to determine the level of slope’s risk: No Risk, Low Risk, Moderate Risk or High Risk. Six slopes have been chosen from Trusmadi Formation and ultrabasic Rocks along Marakau – Ranau Sport Complex. Based on the results of G-Rating, only slope S1 and S4 have value more than 0.4 while other slopes have less than 0.4 which indicates stable slopes. Based on kinematic analysis, all slopes experienced wedge failures with S4 and S5 also have planar failure possibility which show that all slopes have potential instability. D-slope analysis indicates that slope S4 is considered as Moderate Risk with mitigation suggestions are rock anchor and soil nailing with further actions required. Slope S1 is categorized as Low Risk with suggestions of stream system inspection and vegetation on exposed area of the slopes, while other slopes (S2, S3, S5 and S6) have no suggestion for mitigation as been assessed as No Risk.
Authors and Affiliations
Hennie Fitria Wulandary Soehady Erfen, Aiman Nabila Abdul Malik
MEASURED SECTION FOR THE POSSIBLE STRATOTYPE OF THE MIRI FORMATION, AT MIRI HILL, NORTH SARAWAK, MALAYSIA
The Miri Formation is continuously studied by many researchers in various aspects and disciplines in geology due to the important petroleum reservoir since the period of production in 1920-1941. The aim of this study is...
TUNNEL EVALUATION IN CROCKER FORMATION BY GEOLOGICAL STRENGTH INDEX (GSI) SYSTEM: A CASE STUDY
This study was conducted to determine the value of Geological Strength Index (GSI), to predict rock mass properties, very unfavourable discontinuities combination and tunnel support pressure for rock bolts or shotcrete a...
Kampung Mesilou landslide: The controlling factors
This landslide study was conducted in Kampung Mesilou, Kundasang. Desk study, field study and data analysis used were based on recorded slides occurred in 2008, July 2013, November 2013 and June 2015. These episodic land...
Comparison of Cohesion (c’), and Angle of Internal Friction (Ф’) Distribution in Highland Area of Kundasang by using Ordinary Kriging and Simple Kriging
The objective of the research is to determine the distribution of cohesion (c’), and angle of internal friction (Ф’) values for the highland area of Kundasang, Sabah by using kriging. A set of data from two adjacent site...
Rock Slope Stability Assessment of Limestone Hills in Northern Kinta Valley, Ipoh, Perak, Malaysia
The uniqueness of karsttopography in Kinta Valley lies with the spectacular shape of the steep-sided limestone towers. However, theinstability ofthese hillslopes may affect the vulnerability of the surrounding area. Thus...