Articles

  1. MECHANISM AND CHARACTERISTICS OF THE LANDSLIDES IN BONE BOLANGO REGENCY, GORONTALO PROVINCE, INDONESIA Download Article

    Indriati Martha Patuti, Ahmad Rifa’i and Kabul Basah Suryolelono
    • Article Type: Research Article
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    • Pages (1-8)
    • No of Download = 880

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    One of the regencies in Gorontalo Province, Indonesia, Bone Bolango is an area in which landslides occur frequently. This study was at identifying the mechanism and characteristics of landslides in Bone Bolango Regency. This study is important to minimize hazards caused by this disaster. Data were obtained from the results of site survey, surface geological survey and geotechnical investigation. Cohesion during the dry season ranged between 0-15kPa, and the angle of internal friction ranged between 30o-44o. The topography of this area indicates a steep slope (>40°), with weathered rock and discontinuity. These internal factors made the slopes prone to landslide. Meanwhile, external factors that trigger landslides are high precipitation (>100mm), the absence of vegetation covering the slopes, as well as land use on the slopes. In general, the types of the landslide in the study area were debris flows, rotational slides, and rock falls. At the period of high precipitation, the rate of infiltration of rainwater into the soil was slower than the rate of the increase in the volume of rainwater deposited and flowing into the slope surface, resulting in the debris flow. Slope-forming material became soft due to the rise of groundwater levels. This caused a decrease in shear strength and pore water pressure that turned into positive. In the rock slope, rainwater filled the crack of slope discontinuity area so that rock got loose and fell freely. Therefore, a further research is necessary to conduct in order to determine the most accurate and efficient method for slope stability.

  2. COMPARISON OF BEARING CAPACITY OF FOOTINGS WITH SAME AREA RESTING ON REINFORCED SAND Download Article

    Masoud Makarchian and Ehsan Badakhshan
    • Article Type: Research Article
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    • Pages (9-16)
    • No of Download = 5217

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    The Paper presented from an experimental study for circular and square footing with same area that resting on sand bed. The steel model footing with 12 cm diameter (113 cm2) and square footing with 10.6 cm width in sand with relative density 60% were used. For reinforced conditions geogrid layers were used. The settlement-load responses of the tests were investigated. Results indicated that ultimate bearing capacity increased in square footing in comparison with circular footing, and when reinforcements used with embedment depth (u/D=0.42 or u/B=0.47), the bearing capacity ratio (BCR) was increased greatly in circular footing in comparison with square footing. The BCR increases with increasing the number of geotextile layers for both of the footings (square and circular) but for reinforced conditions the geogrid layers have a better effect for circular footing in comparison with square footing and the rate of increasing BCR for circular footing is higher than square footing.

  3. RETENTION STUDIES ON ARSENIC FROM AQUEOUS SOLUTIONS BY LIME TREATED SEMI ARID SOILS Download Article

    Arif Ali Baig Moghal, Krishna R Reddy, Syed Abu Sayeed Mohammed, Mosleh Ali Al-Shamrani and Waleed M Zahid
    • Article Type: Research Article
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    • Pages (17-24)
    • No of Download = 516

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    In this study, locally available semi-arid soils (Al-Ghat and Al-Qatif) having different chemical and mineralogical characteristics are considered as barrier materials, and their response to arsenic adsorption at varying initial concentrations, pH conditions, temperature and dilution ratios is studied. Empirical models (Langmuir and Freundlich) are applied to ascertain monolayer or heterogeneous adsorption. Lime is added to these soils in order to enhance their geotechnical properties. Kinetic models are employed to validate the type and nature of arsenic sorption onto these soils (whether pseudo first-order or second-order). Also Elovich and intraparticle diffusion models revealed that along with surface adsorption, chemisorptions and diffusion are the other processes occurring concurrently in the system, but it was not able to identify the dominant phenomenon among these models. It was concluded that both Al- Ghat and Al- Qatif soils when amended with lime can attenuate arsenic, and the experimental results correlate well with selected empirical models.

  4. THE GEOTECHNICAL PROPERTIES OF RECYCLED CONCRETE AGGREGATE WITH ADDITION OF RUBBER CHIPS DURING CYCLIC LOADING Download Article

    Wojciech Sas, Andrzej Głuchowski and Alojzy Szymański
    • Article Type: Research Article
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    • Pages (25-32)
    • No of Download = 634

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    The following paper presents the results of tests performed on the reclaimed waste, namely the Recycled Concrete Aggregate (RCA). Geotechnical study was undertaken, in order to obtain physical and mechanical properties of RCA improved with rubber grains. Such a mix could exhibit increased elastic strain development during load cycles, which are typical for traffic. For better understanding of its exceptional behaviour under repeated loading, cyclic CBR tests were conducted in various stages of loading. For the purpose of bearing capacity analysis, uniaxial test was also conducted. While the cyclic loading and mechanical stabilization are a cause of aggregates crushing, another particle size distribution could occur and may not fulfil quality requirements. Determination of resilient modulus Mr on the basis of a repeated loading test and development of displacements during the tests have also been presented. The Mr value for pure RCA was equal to 495.6MPa. The addition of rubber chips in amount 0.5% and 1% results in rise of resilient modulus value, equal to 632.4MPa and 698.0MPa respectively. During the tests the plastic strain abate was recognised. The plastic displacement analysis shows increase of the permanent settlement due to cyclic loading in case of 0% and 1% rubber chips content. The 0.5% rubber chips addition results in smaller plastic displacement. The plastic and elastic displacement was later analysed in order to characterize the deformation behaviour of RCA. The paper proposes also a possible guideline for using the RCA mix as a material in pavement subbase construction.

  5. ENHANCING TENSILE STRENGTH IN CLAYS USING POLYPROPYLENE FIBERS Download Article

    Muawia A Dafalla, Arif Ali Baig Moghal and Abdul Kareem Al-Obaid
    • Article Type: Research Article
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    • Pages (33-37)
    • No of Download = 641

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    The geotextile industry research and development is growing at a fast rate and new products of variable specifications are now available for earthworks and design engineers. The polypropylene fiber material is non-biodegradable which can stand aggressive chemical exposure when placed along with soil media. This research is conducted on a polypropylene fiber reinforced soil treated with chemical admixture in order to study the interlocking mechanism and to study the extent of improvement on their tensile behaviour. Locally available plastic clay was selected for this investigation. The extent of improvement by the polypropylene fibres inclusion on the tensile behaviour was evaluated by carrying out a series of Brazilian tensile strength tests. The dominant mechanism responsible for the increase in tensile strength properties has been proposed. The effect of various geotechnical parameters like grain size distribution, density and moisture content on the tensile strength improvement has been discussed. The study shows that the addition of polypropylene fibers alone to highly plastic clay will not suffice the tensile strength requirements. The polypropylene fibers when added with lime of 6% can improve the tensile strength by further 13 to 28% depending on the dose or fiber content.

  6. ADSORPTION STUDIES OF LEACHATE ON COCKLE SHELLS Download Article

    Zawawi Daud, Mahmoud Hijab Abubakar, Aeslina Abdul Kadir, Abdul Aziz Abdul Latiff, Halizah Awang, Azhar Abdul Halim, Aminaton Marto
    • Article Type: Research Article
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    • Pages (46-52)
    • No of Download = 856

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    Sanitary landfills are important means of disposing municipal solid waste in developing countries. However, these landfills are associated with the generation of leachate, which if untreated may pose severe public health risk and may damage the ecosystem in the long term. In this study, cockle shells were explored as an adsorbent media for the treatment of a stabilized landfill leachate. The optimum shaking speed, pH, and dosage for chemical oxygen demand (COD) parameter removal were investigated using the adsorbent media of particle sizes ranging from 2.00 mm to 3.35 mm. Leachate characteristics were then determined. Results indicated that leachate is non-biodegradable with high concentrations of COD (1763 mg/L), ammonia nitrogen (573 mg/L), and biochemical oxygen demand/COD (0.09). The optimum conditions for shaking were determined at 150 rpm according to the adsorption of COD by the media. Optimum pH and dosage was 5.5 and 35 g/L, respectively. The adsorption isotherms indicated that Langmuir isotherm is better fitted than Freundlich isotherm.

  7. EVALUATION OF FLOW-ABILITY ON FLUIDIZATION TREATED SOILS BASED ON FLOW ANALYSIS BY MPS METHOD Download Article

    Shinya Inazumi, Masaki Kaneko, Yoshio Tomoda, Yuji Shigematsu and Ken-ichi Shishido
    • Article Type: Research Article
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    • Pages (53-58)
    • No of Download = 757

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    Recently, fluidization treated soils have come to be used as landfill materials or fillers in such landfill of underground space in Japan. However, the design and construction of the fluidization treated soils at present is based only on empirical knowledge. Therefore, taking into account the findings based on a theory is thought to be useful. In this study, it has evaluated the flow-ability of the fluidization treated soils based on the flow analysis by the MPS method and the experimental evaluation. Favorable results have been obtained in the numerical flow analysis by using the Bingham model to the MPS method. In addition, the authors have developed a fluidization treated soil with increased flow-ability (super-fluidization treated soil). It has evaluated from two aspects of mechanical properties and flow properties of the high flow of the super-fluidization treated soil. The flow properties show that it has a high flow-ability than the fluidization treated soil.

  8. A DEVELOPED PROCEDURE FOR PREDICTING THE RISK OF LIQUEFACTION: A CASE STUDY OF RASHT CITY Download Article

    Mehran Naghizadeh rokni, Mohamadreza Hassanlo and Mohamadreza Ramzani
    • Article Type: Research Article
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    • Pages (59-65)
    • No of Download = 541

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    Soil liquefaction is one of the most important and complex seismic geotechnical and engineering topics. Most experimental methods in the study of liquefaction have been based on deterministic analysis, and parameters, such as soil resistance and earthquake loads, have been considered without dispersion and fault. Statistical analysis, particularly reliability analysis, is a new and comprehensive approach used to solve and evaluate problems, as well as entering of uncertainties in calculations. In this study, information on 50 boreholes were obtained using a database of Standard Penetration Test (STP), and diverse experimental procedures, such as NCEER2001, Idriss and Boulanger, Highway bridge of Japan, OCDI and reliability approach, were used in the evaluation of soil liquefaction in Rasht and finally, the results were compared with each other. By comparing the different methods, it was observed that these methods do not correspond with clay soils and their results were different from each other. Also, safety factor of greater or lesser than one is the mean of safety and occurrence of liquefaction, therefore, reliability analysis was used to ensure the probability of liquefaction. Finally, two empirical relationships based on the probability of liquefaction (PL) and safety factor (FS) were proposed from which the liquefaction potential can be calculated directly. Soil liquefaction risk can be assessed by the proposed relationship between (PL) and (FS) based on deterministic approaches.

  9. AN ALGEBRAIC AND COMBINATORIAL APPROACH TO THE CONSTRUCTION OF EXPERIMENTAL DESIGNS Download Article

    Julio Romero and Scott H. Murray
    • Article Type: Research Article
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    • Pages (66-72)
    • No of Download = 485

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    Experimental design is a well-known and broadly applied area of statistics. The expansion of this field to the areas of industrial processes and engineered systems has meant interest in an optimal set of experimental tests. This is achieved through the use of combinatorial and algebraic approaches. As such, the present study states the theoretical basis to construct and enumerate experimental designs using non-isomorphic mathematical structures in the form of matrix arrangements called orthogonal arrays (OAs). These entities are characterized by their number of rows, columns, entries (symbols), and strength. Thus, each different column could represent some measurable feature of interest (temperature, pressure, speed). The runs, expressed through OA rows, define the number of different combinations of a particular design. Similarly, the symbols allocated in OAs’ entries could be the distinct levels of the phenomenon under study. During the OA construction process, we used group theory to deal with permutation groups, and combinatorics to create the actual OAs following a particular design. The enumeration process involved the use of algebraic-based algorithms to list all possible combinations of arrays according to their isomorphic equivalent. To test isomorphism, we used graph theory to convert the arrays into their corresponding canonical graph.
    The outcomes for this study are, firstly, a powerful computational technique to construct OAs from 8 to 80 runs; and secondly, additions in the published list of orbit sizes and number of non-isomorphic arrays given in [1] for 64, 72, and 80 runs.

  10. EFFECT OF NANO SILICA ON CONCRETE BOND STRENGTH MODES OF FAILURE Download Article

    Mohamed I.Serag, Ahmed M.Yasien, Muhammad S. El-Feky and Hala Elkady
    • Article Type: Research Article
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    • Pages (73-80)
    • No of Download = 551

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    Steel bars are required in order to provide the concrete with the tensile strength that is needed in structural concrete. Bond means the interaction between reinforcing steel and the surrounding concrete, which allows transferring of tensile stress from the steel into the concrete and vice versa. The best ways to enhance the concrete bond strength are by improving the ITZ between aggregates and the mortar between aggregates and the steel re-bars. Recently, those ways were achieved by using pozzolanic materials. The presented research aims to study the effect of adding nano silica (up to 4.5%) on the concrete-steel bond modes of failure. The results revealed that by the addition of 3% nano silica as partial replacement of cement (wt.%), the compressive, splitting tensile, splitting bond and pull out bond strengths increased by 43.5, 12, 16 and 38.5% respectively as compared to normal concrete. It was also concluded that Nano silica enhanced the bond strength for both modes of failure, Pullout and splitting, due to the improvement in the mechanical properties.

  11. ANALYSIS OF FRACTIONAL FLOW AND RELATIVE PERMEABILITY OF HEAVY OIL AND KEROSENE DURING RECOVERY IN PETROLEUM RESERVOIR Download Article

    Abdul Jamil Nazari and Shigeo Honma
    • Article Type: Research Article
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    • Pages (81-88)
    • No of Download = 850

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    This paper evaluates and compares the effect of fractional flow and relative permeability of heavy oil and Kerosene during recovery in a petroleum reservoir. Water fingering is one of the challenging problems during oil recovery and another comprehensive problem is, to exactly evaluate the amount of recover oil from a petroleum reservoir. To address these problems, the fractional flow and relative permeability of heavy oil and Kerosene are analyzed. The fractional flow approach is originated in the petroleum engineering literature and employs the saturation of one of the phases and a pressure as the independent variables. The fractional flow approach treats the multi-phases flow problem as a total fluid of a single mixed fluid and then describes the individual phases as fractional of the total flow. Laboratory steady state flow experiments are performed in two different types of oils (Heavy oil and Kerosene), to empirically obtain relative permeability and fractional flow curves, which have great influence in recovery efficiency calculation. Therefore, the famous Buckley-Leverett displacement mechanism has been used to calculate the performance of waterflooding. With Buckley-Leverett method, oil recovery from waterflooding is calculated and required water injection volume to achieve that oils recovery are estimated for heavy oil, which the total amount of oil produced up to the breakthrough is A φ B ×RF = 15901.92 m3 (= 99864.05 barrels) and for Kerosene is A φ B ×RF = 24992.06 m3 (156950.16 barrels). Additionally, the front flow of heavy oil is approximately spread to 80 m, and the front flow of light oil is approximately spread to 300 m. As a result indicates that fractional flow theory predicates a stable frontal displacement of all mobility ratios contrary to observed experimental facts. Therefore, fractional flow theory is suitable for describing the performance of stable displacement of oils by water.

  12. SPECTROSCOPIC CHARACTERIZATION OF A NIGERIAN STANDARD SAND: IGBOKODA SAND Download Article

    Oluwapelumi O. Ojuri, Jonas Shai, Abiodun D. Aderibigbe
    • Article Type: Research Article
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    • Pages (89-98)
    • No of Download = 804

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    The characterization of the Nigerian Igbokoda Standard Sand was performed by X-ray diffraction, IR and Raman Spectroscopy, and nuclear magnetic resonance techniques. The principal reflections occurring at the d-Spacings of 4.25745, 3.34359, 2.45705, 2.28172, 2.23697, 2.12754, 1.98036, 1.81827, 1.54178 and 1.37190 Å confirm the presence of α-quartz crystalline structure in the cample. The calculated unit cell parameters are: a = 4.9133(2) Å, c = 5.4053 Å, V = 113.00 Å. Presence of Si-O asymmetrical stretching vibrations at 1119.61 – 967cm-1, Si-O asymmetrical stretching vibration at 1180 – 1120cm-1 and Si-O Symmetrical Bending Vibration 693cm-1 reveal the presence of quartz and that it is in the crystalline form. Bands at around 800cm-1 - 822.79cm-1 and 786.23cm-1, reveal that the silica is in the form of α-Quartz. The Raman spectrum of the sample has two peaks at around 203cm-1 and 463.07cm-1 for A1 vibrational mode characteristic of quartz. These peaks reflect that the sample studied belongs to the low temperature quartz. The occurrence of the Raman shift at 463.07cm-1 supports the observation from XRD studies which establishes that the quartz observed in this work is α-Quartz. The 29Si NMR spectrum shows a prominent signal at –107.95 ppm correlating to quartz.

  13. STATE OF AMBIENT AIR QUALITY IN MARRAKECH CITY (MOROCCO) OVER THE PERIOD 2009 – 2012 Download Article

    Manal Inchaouh, Mohamed Tahiri, Bouchra El Johra and Rachid Abboubi
    • Article Type: Research Article
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    • Pages (99-106)
    • No of Download = 620

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    The strong urbanization and the socio-economic development of a city cause serious effects on its environment and its population; our study focuses on the air quality of Marrakech city in Morocco, it’s the first integral study done for that city. We will give a synthesis of air pollutants measurement results; conducted in the city over the period 2009-2012; in order to determine the spatial and temporal variations of major pollutants (NOx; SO2; O3; PM10) measured at the air quality monitoring stations; as well as the weather parameters which are essential to understand the dispersion of this pollution. The results showed that the NOx levels are depending on the local emissions density and the nature of the road network. The concentrations of SO2 are low compared to the admitted Emission Limit values (ELV); this is owing to the weak industrial activity of the city and the use of less polluting fuel (350 ppm diesel).As of particles (PM10); related to road traffic; industry and natural sources; their levels exceed the thresholds limits over all sites. The city is also subject to photochemical pollution mainly due to its geographical location (strong sunlight). During the spring and the summer; the concentrations of O3 reaches an alarming levels with significant overshoot periods of the permitted limits. This study allows us to establish a first approach on the state of the air quality of Marrakech without assessing the contribution of each source; which requires a further study to identify the phenomenon.

  14. IDENTIFICATION OF VULNERABLE AREAS TO FLOODS IN KELANTAN RIVER SUB-BASINS BY USING FLOOD VULNERABILITY INDEX Download Article

    Nurul Farahen Ibrahim, Noorul Hassan Zardari, Sharif Moniruzzaman Shirazi, Mohd Ridza Bin Mohd Haniffah, Shazwin Mat Talib, Zulkifli Yusop and Siti Mariam Akilah Binti Mohd Yusoff
    • Article Type: Research Article
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    • Pages (107-114)
    • No of Download = 845

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    Flood vulnerability indices for the Kelantan River sub-basins were developed from various flood-related variables. The vulnerability indices of the Kelantan River sub-basins involved flood depth-inundation area, soil erosion potential, and potential of soil for agricultural use, population vulnerability, road infrastructure vulnerability and market infrastructure vulnerability. These indices were developed from the use of Geographic Information System (GIS) technique. The result indicates that the flood vulnerability indices of sub-basins were mostly ranked high in the areas with high concentration of development activities and densely populated region with large infrastructure existence that are more flood-prone group than others especially in major metropolitan areas. In order to steer against probable damage caused by flood, it remains important to develop a tool that is most beneficial for river basin managers and policy makers, so that they can conduct vulnerability assessment and flood risk in term of human lives losses and property damages during future massive floods. The output of this study can guide decision makers to reduce flood risks Kelantan River basin in future.

  15. PHYSICO-CHEMICAL AND GEO-ENVIRONMENTAL BEHAVIOR OF SEMI ARID SOILS Download Article

    Waleed M Zahid, Arif Ali Baig Moghal, Ali Abdul Kareem Obaid, Mosleh Ali Al-Shamrani and Syed Abu Sayeed Mohammed
    • Article Type: Research Article
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    • Pages (115-123)
    • No of Download = 734

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    Soil is a basic building block for the most terrestric ecosystems and a complex heterogeneous medium consisting of both solid and fluid phases. Their physico-chemical characterization is of prime importance in understanding their prospective in various civil engineering applications. On the other hand, the ability of soils in absorbing and desorbing metal ions from the aqueous phase assumes importance since it governs both the environmental and agricultural issues. In this study, two different types of soils originating from diversified terrains of Saudi Arabia have been chosen and their potential application in various geotechnical and geo-environmental applications validated by carrying out typical characterization tests, including particle size distribution, density, shear and swelling characteristics. Further, in order to validate their potential applicability in typical landfill liners to retain toxic metal ions, their relative performance in retaining the heavy metal ions has been evaluated. Heavy metal ions such as copper and chromium were used to carry out sorption studies. Experimental data was used to plot adsorption isotherms. Langmuir isotherm was found to be more suitable than Freundlich isotherm for both the soils. It is observed both the soils, exhibited different physical and chemical characterization due to their difference in particle size gradations, as well as in mineralogy and surface morphology. Further, it is concluded that Al-Qatif soil can be used as a filter material and Al-Ghat soil as the main liner material to attenuate selected heavy metals, when they are used in the construction of a typical industrial landfill liner.

  16. RANKING OF SKUDAI RIVER SUB-WATERSHEDS FROM SUSTAINABILITY INDICES – APPLICATION OF PROMETHEE METHOD Download Article

    Irena Naubi, Noorul Hassan Zardari, Sharif Moniruzzaman Shirazi, Nur ‘Asikin Roslan, Zulkifli Yusop and Mohd Ridza Bin Mohd Haniffah
    • Article Type: Research Article
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    • Pages (124-131)
    • No of Download = 853

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    In this study, ranking of sub-watersheds in the Skudai River watershed was developed from the sustainability index. The watershed sustainability index (WSI) was developed by considering two important parameters such as potential flood damages (PFD) and potential water quality deterioration (PWQD) parameters. Preference Ranking Organization Method (PROMETHEE), a multicriteria decision making (MCDM) method, was used and WSI scores for 25 Skudai River sub-watersheds were produced. Based on the WSI score, a ranking of sub-watersheds was developed to locate the more problematic areas in the Skudai River watershed. The middle and lower parts of the Skudai River watershed were found to have considerably low sustainability score which suggested the degradation of sub-watersheds from water quality and flood damage parameters. The ranking of sub-watersheds in this study will assist planners and decision makers to identify the problematic areas within the watershed so that priority interventions can be built before the problem gets worse and affects other areas of the Skudai River watershed.

  17. GENERAL REGRESSION NEURAL NETWORK MODELING OF SOIL CHARACTERISTICS FROM FIELD TESTS Download Article

    Dahlia H. Hafez, A.G. Mahgoub and Mostafa A. Abu Kiefa
    • Article Type: Research Article
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    • Pages (132-139)
    • No of Download = 792

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    The Standard Penetrating Test (SPT) can be considered as one of the most common in-situ popular and economic tests for subsurface investigation. Therefore, many empirical correlations have been developed between the SPT N-value, and other properties of soil. The principle objective of the current study is to demonstrate the feasibility and efficiency of using artificial neural networks (ANNs) to predict the soil angle of internal friction (Φ), the soil modulus of elasticity (E) and tip resistance (qc) of cone penetration test (CPT) results from SPT results considering the uncertainty and non-linearity of the soil. In addition, ANNs are used to study the influence of different input parameters that can be used to improve the prediction. A large amount of field and experimental data including SPT/CPT results, plate load tests, direct shear box, grain size distribution was obtained from a project in the United Arab Emirates to be used in the training and the validation of the ANNs. The ANN results are compared with some common traditional correlations. The results show that the developed ANNs can efficiently predict the aimed parameters from the SPT results. The predicted parameters from ANN are in very good agreement with the measured results compared to the predicted values from available traditional correlations.

  18. INTRINSIC COMPRESSION CHARACTERISTICS OF AN EXPANSIVE CLAY FROM WESTERN AUSTRALIA Download Article

    Farzad Habibbeygi, Hamid Nikraz and Amin Chegenizadeh
    • Article Type: Research Article
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    • Pages (140-147)
    • No of Download = 1381

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    Intrinsic compression behaviour of an expansive clay from Western Australia is investigated using the intrinsic framework in this study. Oedometer results conform with the intrinsic concept at post-yield phase. However, there is a great impact of initial water content on the compression curves at pre-yield stage. It specifies that there is an initial structure similar to a natural clay structure which resists applied forces at this phase and it is related to the amount of initial water content at the preparation stage. Nonetheless, this interparticle bonding is demolished when vertical stress becomes greater than remoulded yield stress. The findings also show that the remoulded yield stress of a reconstituted clay decreases non-linearly with the increase of initial water content, and is remarkably affected by its clay mineralogy. The remoulded yield stress of a soil with the predominant clay of smectite is far greater than those of other clay minerals despite having the same normalised initial void ratio value. Moreover, remoulded yield stress of an expansive soil with main clay mineral of smectite decreases more abruptly than for other clay minerals reported in the literature. Reconstituted compression indexes for clays with a considerable amount of smectite are also greater than respective values for other clay minerals.

  19. SCREW-IN SOIL NAIL FOR SLOPE REINFORCEMENT AGAINST SLIP FAILURE: A LAB-BASED MODEL STUDY Download Article

    Chee-Ming Chan and Muhammad Halim Ab. Raman
    • Article Type: Research Article
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    • Pages (148-155)
    • No of Download = 13059

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    Slope failures occur when the shear resistance along the slip plane is exceeded. This can be caused by excessive load imposed at the slope crest or compromised stability of the slope, e.g. disturbed dimensions of the slope. In order to prevent slope failure, stabilisation or reinforcement measures need to be taken. A common solution is to intercept the slope failure plane with reinforcement elements, such as soil nails and ground anchors. In soil nailing, reinforcement bars are installed on the slope to effectively resist the additional shear forces from the imposed loads, hence reducing the probability of failure in the long run. This paper describes the innovation of soil nail with screw-in installation mechanism instead of the conventional push-in approach. The screw-in installation ensures better soil-nail grip and less disturbance during the slope stabilisation procedure, especially in terms of noise and spoils. In addition, the novel nail has a hollow stem which improves shear resistance with greater soil-nail surface contact on the inner wall. The opening at the nail head also enables displaced air to escape as the nail is screwed into the slope and soil pushed into the inner hollow cavity. The prototype nails were tested in a slope model with different configurations, and were found to reduce the Angular Distortion Ratio by 37 % and the Volumetric Deformation Index as much as 33 % respectively. The novel screw-in soil nail could be potentially used to stabilize natural and man-made slopes, though full-scale simulations are recommended to formulate the installation procedure and to validate the effectiveness.

  20. DISPERSIVE CLAY STABILISED BY ALUM AND LIME Download Article

    Mahmoud Hassanlourad, Mehran Naghizadeh rokni, Mohamadreza Hassanlo and Akbar Badrlou
    • Article Type: Research Article
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    • Pages (156-162)
    • No of Download = 3154

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    Dispersion phenomenon can cause erosion problems during hydraulic construction projects such as earth dams, channels, hydraulic installations and embankments. However, aluminum sulfate can be used to stabilize dispersive clay. Tests were done to consider the effects of alum and lime additions on shear strength parameters of clay as secondary effects. Clay for samples was taken from the Mirzakhanluo Dam, located in Tarom County, northwestern Zanjan Province of Iran. In this research, the clay sample was subjected to direct shear testing; the clay was tested with optimum moisture under varying percentages of alum (0, 0.3, 0.6, 1, 3, and 5 as percentage of dry soil weight) for 28 days. Also, unconfined tests were conducted on samples with equal amounts of moisture, alum and lime under the different treatment durations of 7, 14, and 21 and 28 days, separately. Results for the direct shear test indicated that the maximum cohesion was recorded in the sample with 1% alum. Results also showed that the internal friction angle decreased in samples with alum percentage up to the level of 0.6% and at levels higher than that it showed an increase. Generally, results showed that soil shear strength was higher in soil stabilized by alum than in unstabilized soil. Results of the uniaxial test, determined that alum and lime additions to dispersive soil and its treatment, compression strength was not limited and elastic modulus showed an increase. The highest evaluations were determined for amounts of elastic modulus and uniaxial strength in soil with 3% lime or 5% alum on the 28th day of treatment.

  21. ASSESSMENT OF POTASSIUM SILICATE BASED SURFACE PENETRATION MATERIALS WITH LOW VISCOSITY IN THE REPAIR OF CONCRETE STRUCTURES Download Article

    Shinya Inazumi, Tomohiro Inazawa, Suttisak Soralump, Osamu Saiki and Hikaru Matsumoto
    • Article Type: Research Article
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    • Pages (163-170)
    • No of Download = 564

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    In recent years, surface penetration has attracted attention as a repair method for concretes structures. Silicate based penetration materials have been used in this method. In this study, visual appearance, water permeability, water absorption, water-vapor permeability, neutralization (carbonation) and chloride ion penetration testing of a silicate based surface penetration material are performed. The protection and waterproofing effects of a silicate based surface penetration material are evaluated based on the results. The silicate based surface penetration material penetrates deeply into the concrete surface, shows self-repair functionality, is effective to the neutralization (the carbonation) of the concrete and improves the performance of waterproofing. The penetration depth of the silicate based surface penetration materials plays an important role in the surface penetration method. Therefore, permeability testing of a mortar specimen, penetration depth testing of the mortar specimens with various silicate based surface penetration materials, viscosity testing of the materials and modelling of the one dimensional penetration into the mortar specimens are performed. The results of viscosity testing and coefficient of permeability suggest that these silicate based surface penetration materials will perform well surface penetration materials.

  22. ASSESSING EARTHQUAKE DAMAGE FOR GAS DISTRIBUTION NETWORKS: UNCERTAINTY ANALYSIS APPLICATION IN TLEMCEN (ALGERIA) Download Article

    Soulimane Ilyas and Zendagui Djawad
    • Article Type: Research Article
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    • Pages (171-177)
    • No of Download = 621

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    It is currently admitted that Repair Rate per kilometer (RR) is one of the most suitable tools to measure the fragility of lifeline structures after earthquake. Many models have been developed during last decades and use seismic parameters. These later are derived from ground motion prediction equations (GMPE). Most of the above mentioned models do not take into account the inherent variability of the GMPE. This paper aims to establish a methodology to derive the repair rate by taking account the variability associated with the GMPE. Through this methodology average as well as weighted average repair rates will be established. In order to apply the developed methodology, a model based on Peak ground velocity (PGV) is chosen. Through a sensitive case study it has been found that the weighted average repair rate is the most suitable. Indeed the obtained results show that the proposed approach leads to stable values of the repair rate whereas values obtained from other methods are not stable. Finally, weighted average values of RR obtained from the developed methodology are compared to conventional values obtained for a single GMPE and without uncertainty at the level of urban area (District of Tlemcen, Algeria). This comparative study shows that the developed methodology leads to interesting results.

  23. EVALUATION OF SAFETY ENGINEERING SYSTEM IN OIL AND GAS CONSTRUCTION PROJECTS IN UAE Download Article

    Ghanim Kashwani and Yasemin Nielsen
    • Article Type: Research Article
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    • Pages (178-185)
    • No of Download = 1090

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    Risk assessment is one of the most critical tools used in the safety engineering system in oil and gas construction projects due to it providing the required protection for the construction activities such as pilling, materials fabrication, and structure installation. The main purpose of risk assessment tool is to provide full protection to the four main elements that are crucial to the oil industry: People, Environment, Assets and Reputation (PEAR). The failure or defect in the risk assessment implementation in the construction stage can potentially lead to catastrophes in the advanced stages such as operation and productions. In oil and gas construction projects many historical oil spill and blow outs occurred due to a lack of efficient risk assessment in the construction phase, resulting in financial and human life losses. There are various factors that contribute to the implementation problem in the construction phase, thus, different aspects should be analyzed in the risk assessment structures to determine how the system is very closely linked. Through data analysis, it is evident that the weakness in the implementation can be related to inadequate policy and framework of the risk assessment. Organizational culture affecting employee safety behavior is another contributing reason for faulty implementation. Many scholars try to analyze the implementation problem in the oil and gas sector, along with other heavy industries, through risk regulations, risk planning and human error. This research exposes the defects and challenges in the risk assessment tool in oil and gas construction projects in UAE through a questionnaire survey. The research shows a gap in the understanding and practice of the risk assessment tool between management and operation, especially in the behavioral effects.

  24. SIMULATION OF CO2 EMISSION AND LAND SUBSIDENCE IN RECLAIMED TIDAL PEAT SWAMP IN BERBAK DELTA, JAMBI-INDONESIA Download Article

    Aswandi, R. H. Susanto, E. Saleh, M. R. Abdillah, and I. Iskandar
    • Article Type: Research Article
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    • Pages (186-194)
    • No of Download = 383

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    Environmental impacts of agricultural drainage in a reclaimed tidal peat swamp in Jambi, Indonesia are investigated. A 3-Dimensional (x,y,t) model is developed to simulate the drainage-driven CO2 emission and land subsidence. The initial condition of water table was obtained from a coupled groundwater-canal model. In the first simulation, several scenarios of drainage width ranged from 0.1 m to 1.5 m are analyzed. Model output for 100-year simulation shows that the 0.8 m drainage (e.g. real condition) releases about 794,000 ton of CO2 or equal to IDR 61.2 billion. In addition, the 0.8 m drainage also causes land subsidence of about 52 cm, and reduces the drainable area up to 62.3%. Note that the impacts are robustly lower (higher) when shallower (deeper) drainage depths are applied. The second simulation uses drainages that are appropriate for particular plants and analyze the selling-profit/emission-loss ratio. Among 16 plantation scenarios, it is found that the highest CO2 emission and land subsidence is caused by industrial forest (e.g., oil palm). Therefore, it reduces the profit significantly. On the other hand, the food crops, such as paddy field, have higher profit/loss ratios than the industrial forests.

  25. RESERVOIR EVALUATION OF BAHARIYA FORMATION IN TUT OIL FIELD, NORTH WESTERN DESERT, EGYPT Download Article

    Neamat Aboelhassan, Elhamy Tarabees and Mohamed Alaa
    • Article Type: Research Article
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    • Pages (195-203)
    • No of Download = 959

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    Tut Oil Field is located in the northwestern part of the Western Desert, Egypt. This work aims to study the subsurface and reservoir characteristics to evaluate the hydrocarbon potential of Bahariya Formation based on subsurface data available from open-hole well log records of nine wells distributed in the area of study. The subsurface geologic setting, in terms of determining the stratigraphic and structural settings, is gained through the construction of different aligned stratigraphic and structural cross sections, isopach and lithofacies maps. The petrophysical evaluation, in terms of determining the petrophysical characteristics; net pay thickness, effective porosity, shale content, water saturation and hydrocarbon saturation, is acquired through quantitative computer processed interpretation. The petrophysical characteristics are illustrated laterally in the form of iso-parametric maps and vertically in the form of litho-saturation cross-plots. According to subsurface study and petrophysical evaluation the most productive area is located in central and southern parts of Tut field. 

  26. OVERVIEW OF ROCK BURST RESEARCH IN CHINA AND ITS APPLICATION IN IVORY COAST Download Article

    Kouame Arthur Joseph KOUAME, Fuxing Jiang, Sitao Zhu1, Yu Feng
    • Article Type: Research Article
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    • Pages (204-211)
    • No of Download = 1163

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    Rock bursts and mining-induced seismic events have serious socio-economic consequences for the Chinese mining industry, as its mines are extended to a specific depth. This paper mainly discusses deep mine hazards and rock burst problems in China. First, the definition of a 'rock burst' is given. The paper also introduces the current situation of deep mining and predicts its influences in Ivory Coast over the next ten years. Second, it explains the dynamic hazards arising from deep mining (the most dangerous hazard in deep mining in China).It then emphasizes that dynamic hazard control is a complex technology system that involve many techniques: evaluation, control, prevention and treatment. The burst technique system involves devices that are highly complex. Finally, the paper presents cases of controlled rock burst using the control technologies described, and considers their applications in Ivory Coast’s deep mining industry.

  27. THE EFFECT OF LIMESTONE AND REHEATING TEMPERATURE ON COLD PAVING HOT MIX ASPHALT Download Article

    Ludfi Djakfar, Hendi Bowoputro, Ricky Akbariawan and Rendi Fadiansyah
    • Article Type: Research Article
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    • Pages (212-219)
    • No of Download = 435

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    The objective of the study is to evaluate the effect of the limestone proportion and reheating temperature to the Marshall characteristics of the cold paving hot mix asphalt (CPHMA) using a natural asphalt from Buton, Indonesia. The mix is prepared and mixed in hot temperature like hot mix asphalt, but laid and compacted at normal temperature. The normal application of this mix is for patchwork, due to its lower performance. In order to upgrade its performance, the research attempts to add limestone material and reheat the mix before laying and compacting.  As many as 60 Marshall specimens were prepared with varied asphalt content, percentage of limestone, and reheating temperatures. The specimen were prepared in two stages: mixing process and compaction process. The mixing process was performed like regular hot mix asphalt. After the mixing, the specimens were placed in a batch for 24 hours. The mixes were then placed in the Marshall tube to prepare the Marshall specimens, compacted, and tested. The results showed that heating the mix to about 42oC significantly improves the mix performance, particularly on its Marshall stability. The existence of limestone in the mix also improved its performance. Based on the results it can be concluded that given some treatments, the CPHMA can be used not only as patching material but also as structural layer material, particularly for low to medium traffic rural road.

  28. PERFORMANCE OF MULTI BLEND CEMENT CONTAINING FLY ASH, GRANULATED BLAST FURNACE SLAG AND LIMESTONE Download Article

    S K Chaturvedi and A K Sahu
    • Article Type: Research Article
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    • Pages (38-45)
    • No of Download = 158

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    Investigations carried out revealed that multi blend cements containing fly ash, granulated blast furnace slag (GBFS), and low- and cement-grade limestone have performance (particularly strength development characteristics) comparable in their respective mortar samples. This paper highlights the impact of the addition of low-grade limestone on the performance of mortar samples prepared using multi blend cements and on the hydration mechanism of neat pastes of multi blend cement. The results indicate that in a multi blend cement of fly ash, GBFS, low-grade limestone and clinker, up to 70 % of clinker can be replaced gainfully and the performance of resultant mortar samples prepared using multi blend cement containing cement-grade and low-grade limestone were comparable. Investigations on the hydration mechanism indicated that hydrated multi blend cements containing low- and cement-grade limestone contained the additional phase of calcium carbo aluminate. Further, the rate of formation of calcium carbo aluminate is comparable in hydrated systems containing both low- and cement-grade limestone. The investigations revealed that the quality of limestone, particularly its calcium carbonate content, did not affect the hydration mechanism in multi blend cement. Therefore, low-grade limestone can be gainfully utilised in the manufacture of multi blend cement.