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  1. NUMERICAL ANALYSIS ON THE OCCURRENCE OF THERMAL CONVECTION IN FLOWING SHALLOW GROUNDWATER Download Article

    Junichiro Takeuchi, Makoto Kawabata and Masayuki Fujihara
    • Article Type: Research Article
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    • Pages (2688-2694)
    • No of Download = 475

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    The occurrence of thermal convection in groundwater could significantly change groundwater flows, and this phenomena could also alter solute transport. In the case of a shallow groundwater, thermal convection might affect the surface water quality because it directly interacts with surface waters such as lakes and marshes. Hence, understanding the conditions that induce thermal convection is important for groundwater management. In this study, the conditions for the onset and decay of thermal convection in a flowing shallow groundwater are investigated by conducting numerical experiments. Through the computational analysis using the attractor reconstruction technique, three flow regime types were found, showing that not only the Rayleigh number, which is a well-known influential factor, but also the groundwater flow rate affects the flow regime.

  2. REVIEW OF CORRELATION BASED ALGORITHMS IN SIGNAL AND IMAGE PROCESSING FOR PATTERN IDENTIFICATION Download Article

    Humera Rafique and Samina Rafique
    • Article Type: Research Article
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    • Pages (2695-2703)
    • No of Download = 969

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    This paper presents a review of applications of Digital Correlation algorithms in pattern identification in signal and image processing. The paper not only describes the correlation function, and its different variants descriptively and mathematically and the algorithms in which these can perform discrimination among several signals, images, video frames and objects within them, it also explains the implementation of these by using synthetic signals, audio signals and images, including alphabetic characters. Apart from this, the paper also includes the pseudo code for better understanding of algorithms from the implementation point of view. The results of all described techniques are presented from unprocessed original signals to their processed from, graphically, and spatially.
    As an extended version [11], this paper presents a few more applications of Digital Correlation related functions for more complex tasks and it has been found that, the Digital Correlation and its related functions are very useful and easy to implement for real life pattern identification problems with enough level of complexity with less computational efforts as an independent algorithm and as a part of a complex algorithm.

  3. CONTROL FRACTURE IN SAND FORMATION USING SMART DRILLING FLUID THROUGHOUT EXPERIMENTAL APPROACH Download Article

    Ahmed Z. NOAH
    • Article Type: Research Article
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    • Pages (2704-2711)
    • No of Download = 3503

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    Control losses in geological formations consider as an important issue in drilling operation. Lost of circulation can be one of the more serious problems that can arise during the drilling of an oil well or gas well. Loss of drilling fluid can result in increased cost, loss of time, plugging of potentially productive zones, blowouts from decreased hydrostatic pressure in formations other than the thief zone, excessive inflow of water, and excessive caving of the formation. Lost circulation occurs through existing high-permeability zones such as highly fractured, vuggy, or cavernous structures or induced fractures when the hydrostatic pressure of drilling fluid exceeds the breaking strength of the formation. Carbonates are good examples of the former case. The following preventive measures can be used however in other cases:1 a) set casing, b) maintain drilling fluid density, c) avoid excessive downhole pressures. d) using high energy ball milling to oil based mud to observe the reduction in fluid loss as a result of the nano-additive, the results were positive indicating up to 27.7% fluid loss reduction due to the ability of the suspended nano-material to form compact impermeable mud cake as a result of its physical properties and increased surface area and interaction potential. Core plugs with pre-determined properties were re-tested after the saturation test and showed encouraging results with up to 15% permeability reduction and 8% porosity reduction.

  4. DEW POINT ELEVATION AND OXYGEN AND HYDROGEN ISOTOPIC RATIOS FOR PRECIPITATION SAMPLED AT OSAKA AND MATSUE, JAPAN Download Article

    Tetsuya Fukano and Hiroyuki Ii
    • Article Type: Research Article
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    • Pages (2712-2716)
    • No of Download = 777

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    Dew point elevation was clarified to be an important factor determining stable isotope values of precipitation. When dew point elevation is high, stable isotope values for precipitation were clarified to increase due to the evaporation process which occurred during dropping from dew point elevation to the ground. In winter wet air from the Japan Sea passes over mountains in the center of Japan and dry air after precipitated at the mountains reaches at the Inland Sea. Subsequently, it is thought that when dew point elevation increases, stable isotope values for precipitation increase with the distance from dew point elevation to the ground then high dew point elevation raises the average isotope value of precipitation. Therefore, the elevation of the precipitation point decreases with an increase of the isotope value. Consequently, altitude effect is thought to be caused by precipitation with high dew point elevation. High dew point elevation and high stable isotope values for precipitation in winter were observed at Osaka in the Inland Sea. On the other hand, these high values at Matsue on the Japan Sea side in winter were rarely observed because of low dew point elevation with wet air.

  5. PREDICTION OF SOIL SETTLEMENT BASED ON CONSTANT PLASTIC INDEX METHOD Download Article

    Abdull Halimand Muhaimin Bin Sulam
    • Article Type: Research Article
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    • Pages (2717-2722)
    • No of Download = 619

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    The development of Constant Plastic Index (CPI) method is an approach model based on the theory of consolidation. The objective behind the development CPI method is to predicts critical state settlement whereby CPI is to achieved secondary settlement and reduced time of consolidation. The development CPI has been derived base on the ultimate soil settlement where soils are classified accordingly using initial void ratio, final void ratio and thickness of soil layers. The linear and non linear soil was developed by the relationship between an exponential stress - void ratio and the parabolic permeability – void ratio. The external forces is normally consolidated soil layers and develop Stratum index factor (SIF) and Void ratio function(VRF) which is composed of such a soil varies non- linearly in deposition. Development of CPI will used to predicts critical state settlement, using Eurelian method By combination of these elements, the Potential Instability of settlement was develop and integrate CS- Rating makes concerted effort to produce CS- statement guidelines and better design strategy for geo -mechanics engineer to involve in soil development settlement analysis. Finally, modification of CPI method can be determine soil settlement by using CS- Rating.

  6. SHEAR RESISTANCE IMPROVEMENT OF OIL-CONTAMINATED BALLAST LAYER WITH RUBBER SHRED INCLUSIONS Download Article

    Chee-Ming Chan and Siti Farhanah S.M Johan
    • Article Type: Research Article
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    • Pages (2723-2729)
    • No of Download = 520

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    Railway ballast, which form an integral part of rail tracks, is highly susceptible to subsistence due to both vibration transmitted by the passing trains, as well as the breakage of ballasts with repeated impact. The resulting subsistence necessitates regular monitoring and maintenance, involving cost- and time- consuming remedial actions, such as stone-blowing and ballast renewal. Measures to minimize the wear and tear effect are therefore desirable to prolong the lifespan of the ballast layer. It is even more critical when the ballast is contaminated with oil and grease from braking wheels and leakages. This paper describes the inclusion of rubber shreds (≤10 mm in length, 1.5 mm thick) derived from the inner tubes of motorcycle tyres in oil-contaminated ballast layer for shear resistance improvement. The tests are mainly carried out in a standard direct shear test setup, i.e. shear box measuring 60 mm x 60 mm. Granitic stones of suitable sizes were sieved and used as representative samples of typical ballast. The samples were soaked in lubricant oil for 14 days to simulate the contamination. The direct shear test results indicated rubber shreds inclusion could effectively improve the shear resistance of ballast and expedient in deformation control with increased ductility of the composites. This could potentially improve absorption of impact, hence reduction of breakages of the ballasts. Clearly both mechanisms contribute to the overall reduced subsistence, accompanied by an increase in the shear resistance. However, further investigations in a dynamic test setup are necessary for verifications prior to field implementation.

  7. DETERMINATION AND STUDY OF RESIDUAL CAPACITY IN OLD BUILDINGS: CASE STUDY OF A VERY OLD BUILDING IN RABAT - MOROCCO Download Article

    Ibtissam Kourdou and Toufik Cherradi
    • Article Type: Research Article
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    • Pages (2730-2733)
    • No of Download = 648

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    The rehabilitation of old buildings implies a change of destination and use of the building. But the change of destination involves renovation works and therefore different live and operating loads. Indeed, the purpose of this article is to determine the influencing factors on the bearing capacity of old buildings: reinforced concrete buildings (poles structure - beams) or masonry buildings (walls bearing structure and metal floor).In order to answer this issue, we will review the different diagnostic methods and study their performance and their applicability in this particular case. The example of this old building presents a case study of calculating the actual capacity of an old building in the historic center of the city of Rabat. The discussed building has structural pathologies. The aim of this study is to recalculate the building’s capacity using the actual characteristics (reinforcing section, coating, concrete quality, masonry quality and the current operating loads based on the current building use) in order to determine the rate of the building’s load. To identify the supporting structure of the building, we have conducted a survey of structural elements on site, which has also identified the structural pathologies. The diagnostic work, developed in this article, has confirmed the structural elements and allowed us to conclude about the bearing capacity of the structure.

  8. STRENGTH IMPROVEMENT CHARACTERISTIC OF CEMENT-SOLIDIFIED DREDGED MARINE CLAY WITH RELATION TO WATER-CEMENT RATIO Download Article

    Chee-Ming Chan
    • Article Type: Research Article
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    • Pages (2734-2740)
    • No of Download = 642

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    Dredged marine sediments were retrieved from a maintenance dredge site for examination on the solidification efficacy. The high plasticity clay (CH) sample had low shear strength and high compressibility, making it unacceptable as a geomaterial for construction purposes. Due to its poor engineering properties, the material was destined for disposal offshore: incurring cost, time as well as contamination risks along the transportation route. With solidification, the soil could be improved for potential reuse in reclamation works, for instance. The laboratory investigation involved admixing ordinary Portland cement with the soil at different water-cement (WC) ratios, ranging from 1.5 to 3.5. Left to mature in a confined, damp environment for periods up to 56 days, the solidified specimens were subjected to the unconfined compression test. The measurements were conducted at predetermined intervals of 3, 7, 14, 28 and 56 days. Duplicate specimens were tested using the unconfined compression apparatus in accordance with BS1377 (1990). The unconfined compressive strength (qu) and Young’s modulus (EP) were derived from the stress-strain plots. Both the strength and stiffness were found to increase with lower WC ratio and prolonged maturing, where the solidified soil transformed from a soft, weak material to that of a hard, strong one. The strength improvement was as high as 2.5 times that of the 3-day old specimens, while the stiffness increased by 4 times for the large strain range, as derived from the compression tests. Expediency of solidifying the soil with cement was further examined by correlating the strength, stiffness and deformation with WC as well as rest period.

  9. STRIP FOOTING SETTLEMENT ON SANDY SOIL DUE TO ECCENTRICTY LOAD Download Article

    Kraker Saber Braim, Syarifah Nur Atiqah Syed Ahmad, Ahmad Safuan A Rashid and Hisham Mohamad
    • Article Type: Research Article
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    • Pages (2741-2746)
    • No of Download = 933

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    This study investigates the effect of eccentricity load on settlement of shallow foundation rested on sandy soil model. A series of small-scale 1g physical modeling tests was carried out by preparing a model of medium dry sand with 50% of relative density on a rigid testing chamber. A rigid plate was used to replicate a strip footing foundation. Three different locations of loading were created which located at the centre, 0.05 B and 0.1 B from the centre with respect to the width of the footing to investigate the eccentricity effect applied from the footing. Close range photogrammetry and particle image velocimetry (PIV) methods were used to examine the failure mechanisms under the eccentricity design load. In this study, the ultimate, allowable bearing capacity and bearing capacity factor (Nγ) under the eccentricity loading were investigated. It was found that with the increasing of footing eccentricity, the bearing capacity decreased with increasing settlement.

  10. A ROBUST HARMONY SEARCH ALGORITHM BASED MARKOV MODEL FOR NODE DEPLOYMENT IN HYBRID WIRELESS SENSOR NETWORKS Download Article

    Abdulqader Mohsen, Walid Aljoby, Khaled Alenezi and Abdulrahman Alenezi
    • Article Type: Research Article
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    • Pages (2747-2754)
    • No of Download = 1219

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    The performance of the wireless sensor networks, composed of static sensor nodes, is significantly influenced by the random deployment. Often, the sensors are scattered incorrectly and hence positioned inaccurately. A frequent criticism of the random deployment of stationary nodes is that it might cause coverage holes in the field being monitored. In this paper, we propose adding mobile sensor nodes after the initial deployment of the stationary nodes to overcome the coverage holes problem. To achieve optimal coverage, we first described the network dynamics using Markov chain model, and then harmony algorithm is employed to find the optimal solution for the added mobile nodes intended for covering of the holes. The proposed algorithm determines the best locations of the mobile nodes that need to be added after the initial deployment of the stationary nodes. The performance of the proposed algorithm was evaluated using several metrics, and the simulation results demonstrated that, compared to similar state-of-the-art algorithms, the proposed algorithm can optimize the network coverage in terms of the overall coverage ratio, coverage degree and the number of additional mobile nodes.

  11. OPTIMIZATION OF LOCAL PARALLEL INDEX (LPI) IN PARALLEL/DISTRIBUTED DATABASE SYSTEMS Download Article

    Mohamed Chakraoui and Abderrafiaa El Kalay
    • Article Type: Research Article
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    • Pages (2755-2762)
    • No of Download = 483

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    The widespread growth of data has created many problems for businesses, such as delay requests; in this paper, we propose several methods of partitioning an index B*Tree in multi-processor machines in parallel/distributed database systems and collaboration between processors when executing multi-queries. When optimizing, indexing automatically comes to mind; we distinguish two types of indexing: B*Tree and Bitmap. Since the advent of multicore computers (multi processors) parallelism becomes an indispensable part of optimization. Our work will focus on partitioning each table on three parts following indexing key partitioning; each processor will host a partition of the index, and the first processor that will finish will immediately take another partition of the index pending according to the priority. The parallelism will reduce the CPU cost then reduces execution time; collaboration between processors will further reduce these costs.

  12. TEMPORAL PATTERNS OF WATER QUALITY VARIATION IN KHLONG U-TAPAO RIVER BASIN, THAILAND Download Article

    Saudee Maprasit, Chaisri Suksaroj and Rotchanatch Darnsawasdi
    • Article Type: Research Article
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    • Pages (2763-2770)
    • No of Download = 499

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    Temporal patterns of water quality variation in Khlong U-Tapao river basin of Thailand were analyzed for 21stations along the river basin. This research objective is to study correlation of water quality by temporal variation of climatic-hydrology in years of 2007-2013. Using multivariate statistical analysis to analyze water quality of dataset 9 parameters such as pH, water temperature (WT), turbidity (TB), conductivity (CD), dissolved oxygen, (DO) biochemical oxygen demand (BOD), total coliform bacteria (TCB), fecal coliform bacteria (FCB) and Ammonia Nitrogen (NH3-N). The results show that seasonal change has affected to water quality by variation of climatic-hydrologic parameters. The climatic-hydrologic water quality relationship is maximum climatic temperature had positive with WT but negative with NH3-N. The temporal hydrologic-water quality relationship is precipitation had positive with TB but negative with WT, pH and DO. Water inflow had positive with TB but negative with WT and CD. Water outflow had positive with TB and DO but negative with WT. Water level had positive with TB, BOD and TCB. The spatial-temporal hydrologic-water quality relationship is river cross-section had positive with WT and CD but negative with DO. The assessment from multiple linear regression equations can explain water quality variations by climatic-hydrologic factors. Therefore, water quality management should be consideration climatic-hydrologic variation to provide basal information for developing improved water pollution control procedures of Khlong U-Tapao river basin.

  13. SEISMIC VULNERABILITY STUDY OF SIMULATED UNDERGROUND STRUCTURES USING NUMERICAL APPROACH Download Article

    Akinola Johnson Olarewaju
    • Article Type: Research Article
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    • Pages (2771-2776)
    • No of Download = 564

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    Solution to the complex phenomenon involving seismic action like accidental explosion could not be easily and accurately achieved except through the use of numerical tool. Various accidental explosion scenarios involving underground structures will require the interaction of quite a number of parameters such as the structures, blast loads, blast duration, ground media, contact definition between the components under consideration, material definition, boundary condition, etc. The numerical tool that is capable of analyzing all these variables to yield the required observed parameters should be examined. This tool should be able to incorporate one or more numerical methods of analysis in its program formulation with a view to simplifying and widening research horizon as well as expanding the application of the numerical tool to other field of research. In the case of modeled underground structures, the required observed parameters after analysis are displacement, pressure, stress and strain which could still be subjected to further analysis.

  14. MODEL DEVELOPMENT FOR OUTBREAK OF DENGUE FEVER SURVEILLANCE SYSTEM IN DISTRICT LEVEL Download Article

    Pongmada Damapong, Peerada Damapong and Supat Jumparwai
    • Article Type: Research Article
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    • Pages (2777-2781)
    • No of Download = 561

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    There is reportedly confirmed that the number of epidemics of dengue fever has increased. Use of health surveillance system on epidemic of dengue fever at the district level is restricted. A study to develop a suitable Model for Outbreak of Dengue Fever Surveillance System (MODFSS) in district level. The 60 participants, including 3 government officers leaders, 10 local leaders, 3 specialists, and 44 village health volunteer of participating in the development of the model. The present study utilized three sets of a database, reported on a monthly basis. These included dengue fever cases, notification in advance of the mosquito breeding sources, problems and obstacles of the related organization and epidemic of dengue fever by the local community leaders. The five approaches to develop of the MODFSS included situational analysis, prototype system design, system test, system improvement and model dissemination. This study was conducted in 10 communities. The MODFSS model application was created at the district level. The model evaluated and monitored epidemic of dengue fever practices of prevention and control actions in communities. The five important constituents of the MODFSS were 1) organizations of epidemiology networks, 2) indicators of epidemic, 3) data collection tools, 4) data analysis and 5) dissemination of information. The MODFSS consisted of six core activities (detection, registration, confirmation, reporting, analysis and suggestion) and four support activities (communication through meeting and brainstorming, training, supervision and resource-provision). The developed MODFSS is an effective of health surveillance suitable for district level.

  15. CHARACTERISATION OF NATURAL POZZOLAN OF "DJOUNGO" (CAMEROON) AS LIGHTWEIGHT AGGREGATE FOR LIGTWEIGHT CONCRETE Download Article

    Willy Juimo, Toufik Cherradi, Larbi Abidi and Luiz Oliveira
    • Article Type: Research Article
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    • Pages (2782-2789)
    • No of Download = 872

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    Cameroon has an appreciable quantity of volcanic pozzolanic materials, but a very low proportion is used as cement additions. These materials are abundant but are rarely or very little used because of the lack or limited of studies to develop, promote and popularize its use naturally as an addition or as aggregates in the production lightweights aggregates concretes. The main objective of this study is to promote these sources of low environmental impact construction materials. Its aim is to characterize and value the natural pozzolan source "Djoungo" as lightweight aggregate for lightweight concrete. Analyses and tests conducted in this study were performed on aggregates produced from this resource. It’s concern the chemical and mineralogical analysis, the production of aggregates (Crushing and Sieving), physical properties (appearance and shape, natural water content, porosity, density and water absorption) and mechanical (Compressive strength, tensile strength and elastic modulus) to optimize the mechanical properties and durability of lightweight aggregate concrete obtained from this resource. Chemical composition is according with ACI (American Concrete Institute) standard on natural pozzolans. Two categories of lightweight aggregates were obtained. Those derived by simply sieving have more than 82% of rolled particles and those obtained after crushing have more than 84% of flatter and elongate particles. The bulk density is ranging around 560-820 kg/m3 and specific density around 1,580-2,730 kg/m3. The water absorption after 48 hours is around 12 to 28% and depending of grading class.

  16. A GENETIC ALGORITHM–BASED APPROACH TO PREDICT PAVEMENT MAINTENANCE STRATEGIES: IRAQI EXPRESSWAY NO.1 CASE STUDY Download Article

    Namir G. Ahmed Alkawaaz
    • Article Type: Research Article
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    • Pages (2790-2795)
    • No of Download = 528

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    The present paper articulates the applicability of genetic algorithms (GAs) as an optimization tool capable of supporting decision-makers (DMs) to make the right decisions throughout the selection of an optimal pavement maintenance strategy and to predict future pavement condition. GAs efficiently take advantage of historical information to locate search points with improved performance. In this regard, pavement condition index (PCI) for the in-service pavement of the selected case study (Expressway No.1 (R4/A) in Iraq) is estimated based on ASTM D6433-11 and using MicroPAVER 6.5.2 software. Moreover, the related field measurements of the in-service pavement distresses are carried out and classified. To predict the optimal maintenance strategy for the pavement segments within the selected pavement portion case study, a GA optimization technique is implemented as an application of stochastic approach using EVOLVER 6.3.1 software to evaluate the pavement performance based on PCI. For the required validation process of the predicted PCI results obtained by the GA technique, predicted PCI results obtained by experts’ opinions based on the design questionnaire were estimated and applied. The statistical validation analyses showed that the predicted PCI values obtained via EVOLVER 6 Genetic Algorithm software seem to be close to those obtained via the analyses of the experts’ questionnaires. Based on the research outcomes, it is concluded that one can recognize using the presented procedure throughout the implementation of stochastic approach in the form of GA to predict the optimal pavement maintenance strategy for in-service pavement.

  17. FLOOD ANALYSIS IN LANGAT RIVER BASIN USING STOCHATIC MODEL Download Article

    Yuk Feng Huang, Majid Mirzaei and Wai Kit Yap
    • Article Type: Research Article
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    • Pages (2796-2803)
    • No of Download = 787

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    This study analyzed the annual maximum stage readings of three rivers in Langat River Basin for flood forecasting using Autoregressive Integrated Moving-average(ARIMA) model. Model identification was done by visual inspection on the Autocorrelation Function(ACF) and Partial Autocorrelation Function(PACF). The model parameters were computed using the Maximum Likelihood (ML) method. In model verification, the chosen criterion for model parsimony was the Akaike Information Criteria Corrected(AICC) and the diagnostic checks include residuals’ independence, homoscedasticity and normal distribution. The best ARIMA models for the Dengkil, Kg. Lui and Kg. Rinching series were (1,1,0), (1,1,0) and (1,1,1) respectively, with their AICC values of 133.736, 55.348 and 42.292. Homoscedasticity was confirmed with the Breusch-Pagan test giving p-values of 0.145, 0.195 and 0.747 for the Dengkil, Kg. Lui and Kg. Rinching models respectively. Forecast series up to a lead time of eight years were generated using the accepted ARIMA models. Model accuracy was checked by comparing the synthetic series with the original series. Results show that the ARIMA models for the rivers and the forecast series were adequate. In conclusion, the Box-Jenkins approach to ARIMA modelling was found to be appropriate and adequate for the rivers. The flood forecast up to a lead time of eight years for the three models exhibit a straight line with near constant streamflow values showing that the forecast values were similar to the last recorded observation.

  18. MESSAGE PASSINGAND LOOPS SOLUTION ALGORITHM BASED ON CUT-NODE TREE Download Article

    Zhang Huanming, Xian Kaiyi, Feng Lijun and Hu Chaokang
    • Article Type: Research Article
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    • Pages (2804-2807)
    • No of Download = 429

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    Low-density parity-check (LDPC) codes are forward error-correction and linear block codes. An LDPC code can be described by a bipartite graph called Tanner graph[1]. Loops, especially short loops in tanner graph, degrade the performance of LDPC decoder, because they affect the independence of the extrinsic information exchanged in the iterative decoding. In this paper, based on graph theory and Tanner graph, the loop structure in LDPC codes are studied carefully, a new notion, cut-node tree, is proposed to describe LDPC codes. Cut-node tree has full information of Tanner graph. So all loop features in LDPCs can be calculated relatively easy by a computer. Traditional message passing in graph is improved to avoid repeated iteration of information, a new decoding schemes for LDPC codes is proposed and can suppress repeated iteration of information in SPA. The results help to further research on related field.

  19. BACK-ANALYSIS OF HOEK-BROWN CRITERION: ROCK SLIDE CASE IN MANADO Download Article

    Rini Kusumawardani, Togani Cahyadi Upomo and Muhammad Faizal
    • Article Type: Research Article
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    • Pages (2808-2814)
    • No of Download = 824

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    The discontinuity of geological structure on tuff layer of rock slopes in Manado triggered a phenomenon of rock slope instability. Mohr-Coulomb criterion which is commonly used as a method of analysis is not suitable to solve the slope stability problem because this criterion does not consider the condition of the geological structure as one of its factors. This paper analyzed the rock slope stability by accommodate the condition of the geological structure using Hoek-Brown criterion. Geological structure effect in Hoek-Brown criterion was realized in the form of GSI (Geological strength index). Poor geological structure will reduce GSI. In this paper, GSI of tuff has been determined by discontinuities of mapping and back analysis. The results from discontinuities mapping revealed that the rock structures were very blocky to blocky and surface conditions were very poor to poor. GSI value ranges between 20-30. From back analysis with shear strength reduction, GSI value was 20 and UCS value was 230 kN. The results are quite close with the field observation.