Articles

  1. BURIED PIPE RESPONSE SUBJECTED TO TRAFFIC LOAD EXPERIMENTAL AND NUMERICAL INVESTIGATIONS Download Article

    Ahdyeh Mosadegh and Hamid Nikraz
    • Article Type: Research Article
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    • Pages (1-8)
    • No of Download = 545

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    In this paper, a flexible buried pipe response subjected to traffic load is investigated through laboratory experiments and numerical analysis. A series of laboratory tests and numerical simulations were carried out to investigate the impact of surface pressure and burial depth on the model response. Experimental tests were carried out using UTM25 to apply load on surface of a tank in which pipe was buried. Numerical simulations were conducted using the Finite Element Method, ABAQUS software to develop a better understanding of the pipe behavior. Results indicate that a good agreement between numerical and experimental test results was observed. In addition, experimental and numerical analysis reveal that increasing burial depth decreases pipe deflection, increases soil surface settlement and decreases pressure on pipe while increasing surface pressure increases all mentioned parameters. From all numerical and experimental results and using the Curve Fitting analysis in Matlab, equations were developed to predict soil surface settlement, pipe vertical diametric strain and pressure on pipe. Cumulative error analysis shows that all predicted parameters have less than 10% error.

  2. COMPARISON OF DIRECT AND INDIRECT MEASURED SOIL-WATER CHARACTERISTIC CURVES FOR A SILTY SAND Download Article

    T. Abeykoon, R.S. Udukumburage, C. Gallage and T. Uchimura
    • Article Type: Research Article
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    • Pages (9-16)
    • No of Download = 368

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    It is time consuming and needs sophisticated testing apparatus to determine unsaturated soil properties such as hydraulic conductivity and shear strength. Therefore, engineers hesitate to use unsaturated soil properties in economical geotechnical problem solving. To promote the use of unsaturated soil properties in geotechnical engineering designs, numbers of methods have been developed to estimate/predict unsaturated soil properties. The Soil-water characteristic curve (SWCC) defines the relationship between the soil suction and water content. During past few decades, different measuring and estimation/prediction methods have been developed by researchers to ascertain SWCC of soils. Among them, direct and indirect methods are widely used to measure the SWCC of soil. Indirect methods such as axis-translation technique are commonly used in the laboratory to determine SWCC. It is important to understand how well the indirectly measured SWCC is related to actual soil-water retention properties of soil during drying and wetting process. Bridging that research gap, in this study, Soil water characteristic curve (SWCC) of sandy soil was measured using both indirect (Axis translation method using Tempe Pressure Cell) and direct methods. The direct measured SWCCs were obtained by subjecting the instrumented soil column and model embankment to wetting and drying cycles. When comparing SWCCs measured by direct and indirect methods, it was found that the indirect method provides a very close agreement with the outcomes of direct methods. This ensures that the SWCCs measured in the laboratory by using indirect methods can be used in Geotechnical Engineering practice.

  3. HYDROCHEMICAL ASSESSMENT OF UNCONFINED AQUIFER SYSTEM IN BAYAT MELANGE COMPLEX, KLATEN, INDONESIA Download Article

    Putranto, T.T., Hidajat, W.K. and Wijaya, H.
    • Article Type: Research Article
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    • Pages (17-24)
    • No of Download = 347

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    The geological setting of Bayat that has a complexity in structural geology as well as a variety of lithology because this region is interesting to be investigated from the hydrogeological point of view. Hydrogeological assessments were conducted based on the hydrogeological and geological mapping, as well as hydrochemical analysis. Groundwater level measurements were carried out at 51 measurement points. There were 25 groundwater samples to be analyzed the ion content by using Ion Chromatography and ICP-OES. There are seven lithology units i.e. Schist-phyllite-marble, Nummulities limestone, Diorite intrusion, Pebbly sandstone, Layered limestone, Colluvial and Alluvial deposit based on the surface geological mapping. The geological structure investigation in Temas Hill conduct the trends of structural orientation that are northeast to southwest. They become the point of infiltration and circulation pathways in the crystalline bedrock. Hydrochemical analysis obtain five (5) groundwater facies. They are Ca-Mg-HCO3, a mix of Ca-Na-HCO3-Cl, Na-HCO3, Ca-SO4 and Na-Cl. The concentration abundances of cation are Na+>Ca2+>Mg2+>K+while HCO3->Cl->SO42->NO3 - represent anion content. A Gibbs diagram shows that the dissolved ions are dominated by rock weathering process. Na+ ion is derived from the weathering of feldspar-rich mineral, Ca2+ and Mg2+ indicate through limestone dissolving. The high Cl- ion content in some samples is predicted from
    the mixing of upwelling fossil water through Trembono strike-slip fault.

  4. EVALUATION OF POROUS HOTMIX ASPHALT PERFORMANCE UNDER ACCELERATED LOADING Download Article

    Ludfi Djakfar, Yulvi Zaika and Harimurti
    • Article Type: Research Article
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    • Pages (25-32)
    • No of Download = 297

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    The purpose of the study is to evaluate the performance of porous hot mix asphalt under accelerated loading. The parameters measured were stresses and deformation (rutting) occurred in the test section. To achieve the objective, a test section was constructed and tested with a loading device, simulating truck loading. Subbase and base layers were constructed using similar materials. The variable is on the surface layers, which consist of two conventional and two porous hotmix asphalt. The pavement material conforms to the Indonesian Directorate General of Highway for the conventional HMA and Australian standard for Porous HMA. The thickness of the test section was prepared to simulate the real condition of the pavement structure. The simulated load applied to the pavement test section was equivalent to the 9,600 kg, which was more than the standard 8,160 kg axle load, and applied for more than 1,500 passes. For every 100 passes, stresses and deformation were recorded. The result shows porous HMA relatively has a comparable performance when compared to the conventional one. Hence, the application of porous HMA needs to be pushed particularly in the area where rain intensity is high.

  5. THERMAL INFRARED REMOTE SENSING OF HYDROCARBON IN LAGOS- SOUTHERN NIGERIA: APPLICATION OF THE THERMOGRAPHIC MODEL Download Article

    Moses E. Emetere, Samuel E. Sanni, Jennifer M. Emetere and Uno E. Uno
    • Article Type: Research Article
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    • Pages (33-45)
    • No of Download = 331

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    The paper presents a technique for investigating remote sensing imagery to explore hydrocarbon sites, oil traps and spills. This research adopts a model approach to oil exploration against conventional or traditional methods. The model used here is the Environmental Thermographic Model (ETM). Key parameters such as surface emissivity, surface temperature, long wave radiation and geological mapping which constitute the model were used alongside data generated from the Moderate Resolution Imaging Spectro-radiometer (MODIS) in order to identify the location of prospective oil or gas reservoir in Lagos-Southern Nigeria. MODIS data generated over a period of ten years was analyzed. The ETM model and a temperature polynomial expansion scheme (TPES) were used to validate the remote sensing data by using calculated surface emissivity and long wave technique. Two thermal infrared sources were deployed to aid oil field investigations. The consistency of the Landsat 8 OLI and ETM imagery further confirms the reliability of the method in determining the characteristics of the hydrocarbon habitat, as well as the lineaments.

  6. DEVELOPMENT FLOW DURATON CURVE FOR CRITICALITY ASSESMENT OF RIVER BASIN APPLIED AT THE UPPER CITARUM RIVER BASIN, INDONESIA Download Article

    Hadi Nurcahyo, Indratmo Soekarno, Iwan K. Hadihardaja Arief Rosyidie
    • Article Type: Research Article
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    • Pages (46-53)
    • No of Download = 382

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    A river basin is a landscape unit in which a hydrologic cycle completely occurs in every respect. River basins, initially healthy and natural, are slipping into critical conditions, affected by urbanization processes. Hydrologic imbalance happens due to land-use change resulting in increased runoff and reduced soil infiltration capability. The change of a river basin from a fine healthy hydrologic condition into a critical state is shown by flow duration curve and its least square line. Having been applied at the Upper Citarum river basin using ArcSWAT hydrologic model and SWAT-CUP calibration program, the curves could map the health range of the river basin showing wheather the river basin was heading towards a critical condition. Based on modeling of FDC on natural and fully utilized condition, the criticality feature is the increase in high flow and decrease in low flow. The upper Citarum river basin was in criticality process which shown by high flow increases and low flow decreases over the period 1981-2010. Using model of FDC’s gradient, the criticality value of the period 1981-1986 was 3.15 and it increased to 3.35 in the period of 2005-2010. The increase is correlated with land use change in increasing settlements, dry crops, barrenland, and forest decline.

  7. DETERMINATION OF THE COMPRESSION INDEX OF RECONSTITUTED CLAYS USING INTRINSIC CONCEPT AND NORMALIZED VOID RATIO Download Article

    Farzad Habibbeygi, Hamid Nikraz and Fred Verheyde
    • Article Type: Research Article
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    • Pages (54-60)
    • No of Download = 399

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    Measurement of the compression indexes of clayey soils, particularly reconstituted clays with
    a high initial water content, is generally time-consuming and costly. A mitigation of these constraints could include a correlation between the compression indexes and the consistency limits of the clay soil that can be measured reliably. In this paper, the time-tested concepts of intrinsic framework and normalisation methods were used to derive a correlation between the compression indexes of reconstituted clays and the soil void ratios at consistency limits. The proposed method is based on the assumption that a unique relationship exists between consolidation pressures and consistency limits. Furthermore, the equation was simplified to estimate the compression index as a function of consistency indexes. Then, the equation was validated via comparison with a wide range of results reported in the literature regarding various types of clay. Results of this comparison suggest that there is an exclusive relationship between compression index and consistency limits for reconstituted clays.

  8. MEASUREMENT OF ARITHMETICAL MEAN ROUGHNESS OF CONCRETE BY TRANSCEIVER TYPE AERIAL ULTRASONIC SENSOR Download Article

    Nagaoka Seiya, Islam Mohammad Raihanul, Okajima Kenji, Ishiguro Satoru, Ito Ryoei, Watanabe Ken and Ito Tetsu
    • Article Type: Research Article
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    • Pages (61-66)
    • No of Download = 325

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    The roughness coefficient of the concrete irrigation canal is one of the important evaluation criteria to ensure the hydraulic performance or malfunction between water and wall surface. In this study, the roughness coefficient of the concrete irrigation canal was measured using the aerial ultrasonic wave of the transceiver type sensor. The effect of the dispersion of measurement values in relation to the arithmetical mean roughness and the peak to peak value of the reflected wave were demonstrated. The influence of wet and dry conditions of concrete surface and the verification of the measurement range were taken into account. Results obtained showed that the peak to peak value of the reflected wave could measure the arithmetical mean roughness of concrete. It was observed that the average of 15 measured values was sufficient for accuracy. The peak to peak value of the reflected wave was affected slightly under wet condition. The range of the measured diameter of aerial ultrasonic wave sensor was approximately 300 mm and 600 mm from the distance of 550 mm and 1000 mm respectively. It is concluded that the development of the measurement method of arithmetical mean roughness of concrete surface by the transceiver type aerial ultrasonic sensor can be achieved.

  9. COMBINATION TECHNOLOGY OF GEOTEXTILE TUBE AND ARTIFICIAL BEACHROCK FOR COASTAL PROTECTION Download Article

    Md. Al Imran, Kazunori Nakashima and Satoru Kawasaki
    • Article Type: Research Article
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    • Pages (67-72)
    • No of Download = 342

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    In recent years, traditional forms of river and coastal structures have become very expensive to build and maintain, because of the shortage of natural rock. Therefore, the materials used in hydraulic and coastal structures are changing from traditional rubble and concrete systems to cheaper, sustainable, and eco-friendly materials and systems such as artificial rock, gabion, slags, geosynthetics, and so on. Moreover, shorelines are being continually eroded by the wave action of the sea, and the river and coastal structures are frequently damaged by both anthropogenic and natural causes such as over wash and storm. How to deal with eroding coastal problems is a main topic of this article. Recently, artificial beachrock and geotextile tube technology has changed from being an alternative construction technique and, in fact, has advanced to become the prime solution of choice. Therefore, the objectives of the present study is to find out the feasibility to protect coastal erosion in Asia along with using artificial beachrock and geotextile tube technology in a cheaper, sustainable and eco-friendly way.

  10. IMPROVED SOIL-PILE INTERACTION OF FLOATING PILE IN SAND WITH SHAFT TREATMENT Download Article

    Chee-Ming Chan and Nurul Ain Mansor
    • Article Type: Research Article
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    • Pages (73-79)
    • No of Download = 333

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    The present study explored the efficacy of pile shaft surface treatment on the improvement of soil-pile frictional resistance for floating or friction piles. 4 surface conditions of model piles measuring 200 mm long and 20 mm in diameter were examined, namely smooth (control), roughened, fishbone and checked shafts. A pile cap made of plywood was fixed to the top of the pile with 10 mm embedment depth, leaving 190 mm clearance for installation in the sand bed. The test chamber was a see-through glass tank with a footprint of 100 mm x 200 mm and 300 mm height. Coarse sand of D50 = 1.5 mm were loosely placed in the chamber by layers up to 200 mm height before the piles were installed either in single or triple group formations. The incremental load test of conducted via application of dead load ranging between 0.01-0.08 kPa on the pile cap, and the corresponding settlement was recorded. The test results revealed settlement to be reduced by the piles in the order of roughened > fishbone > checked > smooth for the single pile configuration, with maximum reduction of 40 % recorded by the roughened pile. As for the pile group, settlement reduction of the piles with surface treatment clearly outperformed the control pile by almost 50 %, though differences between the former were marginal with seemingly overlapping stress-strain plots. All in all the surface treatment of pile shaft enhanced the shaft friction for the piles installed in sand, but field implementation would require further examination of the pile-driving efficiency as the improved piles could cause additional resistance during installation.

  11. APPLICATION OF INDUSTRIALIZED BUILDING SYSTEM: A CASE STUDY IN KANO STATE, NIGERIA Download Article

    Ibrahim Zakari, A.S.M Abdul Awal, Rozana Zakaria, Abdul Halid Abdullah and M. Zakaria Hossain
    • Article Type: Research Article
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    • Pages (80-86)
    • No of Download = 357

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    Development of infrastructures are needed due to the growing population, increasing demand for housing and other building activities and the improvement in the quality of life of the populace. This study has been conducted with the aim to capture the perspective of Nigerian construction industries on the industrialized building system (IBS), specifically in Kano State. The methods adopted for this study comprises of interview session with 5 expert respondents and questionnaire survey with 73 respondents of professionals within the Nigerian construction industries. Data obtained was analyzed using content, frequency and factor analysis through SPSS software. Research findings shows that majority of the construction industry in Kano are commonly practicing traditional cast on site method and IBS implementation is considered in early stage. The setback of IBS application in Kano found from this study is due to insufficient IBS manufacturer, unfamiliarity and resistance to change, enormous capital cost and lack of government interest. In order to overcome these barriers, majority of the respondents agreed that improving the educational curriculum and adopting intensive training for the related parties will help in improving IBS implementation in Kano state and indirectly to Nigeria. The study further concludes that Government support and increase awareness on IBS benefits will result in successful IBS implementation in the state.

  12. EFFECT OF GGBFS AND MICRO-SILICA ON MECHANICAL PROPERTIES, SHRINKAGE AND MICROSTRUCTURE OF ALKALI-ACTIVATED FLY ASH MORTAR Download Article

    Yuyun Tajunnisa,Masaaki Sugimoto, Takahiro Uchinuno, Takahiro Sato, Yoshinori Toda, Arisa Hamasaki, Toru Yoshinaga, Kenji Shida and Mitsuhiro Shigeishi
    • Article Type: Research Article
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    • Pages (87-94)
    • No of Download = 336

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    Performance of drying shrinkage, flow rate, mechanical properties, and microstructure of three materials - alkali-activated fly ash (FA); ground granulated blast-furnaced slag (GGBFS); and un-densified micro-silica (M) are investigated. Mixtures used herein are referred to as AAM – alkali activated materials – of four types according to composition: AAM-IV, AAM-V, AAM-VI and AAM-VII (note: types 1 through 3 were investigated in previous research) with corresponding mixture FA, GGBFS and M ratios of 47.5/47.5/5, 45/45/10, 42.5/42.5/15, 40/40/20 by weight percentage. The AAM samples were air-cured under a sealed condition for 6 days followed by unsealed curing up to the test at 18-20° C and a low relative humidity of 30-50%. The samples AAM-IV through VII were composed of a progressive decrease of fly ash and GGBFS and an increase in M content. Results show that flow rate and compressive strength increased from AAM-IV to AAM-VI; contrarily, it decreased in AAM-VII. Both flexural strength – a positive aspect - and drying shrinkage – negative as it leads to cracking - increased in all samples. Incorporation of both GGBFS and M in alkali-activated fly ash mortar was found to improve performance compared to that incorporated solely of GGBFS in alkali-activated fly ash. The incorporation of M of certain values improves strength and flowability of AAM; conversely, it results in a higher drying shrinkage value, which leads to increased cracking. SEM and XRD results confirm these results. Unreacted particles of AAM-VI and AAM-VII appear to act as a ‘micro-aggregate,’ resulting in increased compressive and flexural strength.

  13. STABILITY CHARTS FOR UNSUPPORTED CIRCULAR TUNNELS IN COHESIVE SOILS Download Article

    Jim Shiau, Brian Lamb, Mathew Sams and Jay Lobwein
    • Article Type: Research Article
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    • Pages (95-102)
    • No of Download = 412

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    This paper investigates the stability of a plane strain circular tunnel in cohesive soils. A strength reduction technique and the finite difference program FLAC, are used to determine the factor of safety for unsupported circular tunnels. Results from the finite difference approach are presented alongside rigorous upper and lower bound limits computed using Optum G2. A thorough comparison between these two methods finds very good agreement. As the model is shown to be accurate, design charts are presented for a wide range of practical scenarios using dimensionless ratios. The potential usefulness of this approach is demonstrated using a number of examples. This is considered a simpler way of analysing the stability of an unsupported tunnel that may be as practical as similar methods used in slope stability analysis, such as the commonly used Taylor’s design charts.

  14. ESTABLISHING RELATIONSHIP BETWEEN MODULUS OF ELASTICITY AND STRENGTH OF NANO SILICA MODIFIED ROLLER COMPACTED RUBBERCRETE Download Article

    Bashar S. Mohammed, Musa Adamu and Nasir Shafiq
    • Article Type: Research Article
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    • Pages (103-110)
    • No of Download = 550

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    Roller compacted concrete (RCC) pavement is subjected to repetitive loadings and bending stresses from moving vehicles. Therefore, they are susceptible to cracks due to fatigue. Dowel bars, tie rods, or steel reinforcement cannot be placed on RCC pavement due to the way they are placed, compacted and consolidated, Therefore, all loads and deformations are resisted by the concrete alone. One of the ways of reducing such effect is producing a more durable RCCP that will undergo higher deformation before cracking. This can be done by partially replacing fine aggregate with crumb rubber (CR) in RCC to produce roller compacted rubbercrete (RCR). In this study, RCR was produced by partially replacing fine aggregate with CR at levels 0%, 10%, 20%, and 30% by volume. Nano silica (NS) was then added at 0%, 1%, 2%, and 3% by weight of cementitious materials to mitigate loss in strength, and their effect on modulus of elasticity (MOE) was studied. The MOE of RCR decreases with increase in CR and increases with NS addition. Also at 10% CR the MOE of RCR increases. Conversely, NS decreases the ductile behavior of RCR by making it more rigid. Power function was not suitable for the relationship between MOE and compressive strength of RCR as recommended by ACI 318, therefore linear model was developed.

  15. A NEW MECHANISTIC FRAMEWORK FOR EVALUATION OF CYCLIC BEHAVIOUR OF UNSATURATED UNBOUND GRANULAR MATERIALS Download Article

    Peerapong Jitsangiam, Suphat Chummuneerat, Korakod Nusit, Tawatchai Tanchaisawat and Hamid Nikraz
    • Article Type: Research Article
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    • Pages (111-123)
    • No of Download = 427

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    The unsaturated unbound granular materials (UUGMs) as a base course layer play a major role in the overall performance of the multi-layered flexible pavement system. In theory, the cyclic response of UUGMs (under traffic loading) depends greatly upon moisture content and matric suction, but these effects have been conventionally difficult to quantify. This paper presents a new mechanistic framework for characterising the cyclic behaviour of UUGMs with differing levels of moisture content and density, and in various in-service stress conditions in pavements without real cyclic testing on UUGMs. These parameters would typically be considered to gain a more precise pavement evaluation. In this study, a normalisation procedure was performed to incorporate matric suction into the cyclic response evaluation of UUGMs with a range of moisture contents and without actual suction measurement. A new soil suction model with three density-independent parameters was derived from a series of static triaxial compression tests based on the traditional triaxial facilities. The suction model developed can be used, with the Bishop effective stress constitutive model, to successfully evaluate the resilient response of UUGMs under the stated conditions. With the inclusion of matric suction, this new mechanical framework provides a more reliable resilient modulus prediction model.

  16. FIELD MEASUREMENT AND NUMERICAL MODELING OF TIDAL CURRENT IN LARANTUKA STRAIT FOR RENEWABLE ENERGY UTILIZATION Download Article

    Harman Ajiwibowo, Kanisius Sagari Lodiwa, Munawir Bintang Pratama and Andojo Wurjanto
    • Article Type: Research Article
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    • Pages (124-131)
    • No of Download = 887

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    The amount of electricity consumed is growing rapidly, along with population growth and technological development. Meanwhile, Indonesia’s energy supply is predominantly supported by non-renewable sources, so an approach to renewable energy is urgently needed. This study uses a numerical model to determine the potency of tidal current power at Larantuka Strait, East Nusa Tenggara Province, Indonesia. The output of the study is the electricity generated with a conversion device at several locations. The numerical model is generated using MIKE 3. In order to validate the numerical model, field measurements are conducted to obtain the detailed bathymetry, tidal surface elevation, and tidal current velocity data. The numerical model shows good agreement with the field measurement data; the average errors of tidal surface elevation and tidal current velocity are 4.04 and 9.79%, respectively. Furthermore, the tidal current model is analyzed and two potential sites are found at the narrowest part of the strait. The generated power is calculated for a D10 Sabella turbine. The calculation shows that the amounts of power generated are 522.972 and 324.12 MWh for the two sites, respectively, in 2014. The study shows that Larantuka Strait is very promising and suitable as a site for a tidal current power plant with its tidal current and water depth. A detailed analysis, including financial, navigation, and environmental studies, needs to be conducted to present the feasibility of the realization.

  17. ESTIMATION OF TUNNELING INDUCED GROUND SETTLEMENT USING PRESSURE RELAXATION METHOD Download Article

    Jim Shiau and Mathew Sams
    • Article Type: Research Article
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    • Pages (132-139)
    • No of Download = 404

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    The prediction of ground settlement caused by tunnelling is frequently estimated using a specified tunnel volume loss, and by applying a semi-empirical method involving the Gaussian equation, and relying on engineer's experiences. One of the key parameters in the semi-empirical method, K, is generally estimated using basic soil classifications, which has the potential to lead to inaccurate judgement from engineers. Better estimation of this constant K has had limited attention by other studies. This research uses a force relaxation technique and the finite difference program, FLAC, to estimate the transverse settlement profile for a range of different scenarios. A number of particular cases are numerically simulated with variation in the factors that influence the tunnel transverse settlement including tunnel depth to diameter ratios (C/D), clay strength ratios (γD/Su), Young’s Modulus (E), and volume loss (% of tunnel). Using these settlement profiles, a K parameter can be accurately fitted for each case. Results from this study compare favourably with previous empirical and analytical studies. A range of K values is proposed for any combination of soil strength, Young’s Modulus, tunnel geometry, and volume loss.

  18. STUDY ON STRENGTH BEHAVIOR OF CEMENT STABILIZED SLUDGE REINFORCED WITH WASTE CORNSILK FIBER Download Article

    Khiem Quang Tran, Tomoaki Satomi and Hiroshi Takahashi
    • Article Type: Research Article
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    • Pages (140-147)
    • No of Download = 441

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    This study was carried out to investigate the strength behavior of cemented sludge reinforced with cornsilk fiber considered as a by-product from corn. Hence, a series of unconfined compression test was conducted at different levels of water, cement, and fiber content. Water contents considered in this study were 40, 50, and 60%; cement content used for sludge stabilization was changed from 5 to 40 kg/m3; meanwhile, fiber content was used at different levels from 5 to 30 kg/m3. In addition, the relationship between failure strength and the amount of water, cement, and fiber was investigated in the present work. The experiment results showed that there was an improvement in failure strength, failure strain, ductility, and stiffness with fiber inclusion. Besides, stiffness improvement was based on the amount of cement used. The relationship between failure strength with and without fiber inclusion and water, fiber, and cement content was described as following power or exponential function with a strong correlation coefficient. It was concluded that there was a good performance of cornsilk fiber in reinforcing cemented sludge. Furthermore, the utilization of waste material to modify soft soil or sludge will bring about many benefits not only for geotechnical engineering but also for the environment and social economy.

  19. LIQUEFACTION POSSIBILITY OF SOIL LAYERS DURING EARTHQUAKE IN HANOI Download Article

    Gospodarikov Alexandr and Thanh Nguyen Chi
    • Article Type: Research Article
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    • Pages (148-155)
    • No of Download = 499

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    Earthquakes are one of the most unpredictable natural phenomena that can damage buildings on the surface as well as underground structures. It is therefore necessary to have an effective and accurate assessment of the impact of earthquakes on existing structures. Hanoi is the capitol and second largest city in Vietnam and contains many historical and important buildings. Previous studies suggest that Hanoi may be affected by earthquakes occurring along the Lai Chau - Dien Bien - Son La and Red River faults. Parameters of earthquakes that could occur in Hanoi are studied using common methods (e.g. Campbell and Seed, etc.). Based on the data collected from the studies about some characteristics of the strongest earthquakes that can occur in the Hanoi area, this study presents an estimate of the possibility of liquefaction of soil layers in Hanoi during an earthquake in combination with experimental results obtained under relevant geological and hydrogeological conditions. 

  20. INVESTIGATION OF THE BEHAVIOR OF SUPPORTING STRUCTURE SYSTEMS AND FINDING THE OPTIMAL METHOD FOR URBAN EXCAVATION Download Article

    Mohsen Farzi, Hesam o Din Aminpour, Alireza Lork and Mohamad Alizadeh Moghadam
    • Article Type: Research Article
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    • Pages (156-163)
    • No of Download = 293

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    Today, the increasing growth of urban construction as a result of urban development necessitates deep excavation in highly dense urban areas, therefore, supporting and securing excavation by appropriate methods have become of crucial importance. In such conditions, common and widely used methods of excavation support will be used by designing engineers. However, each of these methods has its own disadvantages and limitations. Therefore, these methods cannot be used in various conditions with different geotechnical and site properties. In such cases, an accurate analysis of the condition can help the engineers to select and design the supporting and stabilizing system. In this regard, different methods have been used by engineers, among which numerical methods have led to appropriate results. In this study, a series of numerical analyses by the finite element code PLAXIS2D was used for investigating the behavior of an excavated zone in the central region of Ahvaz which has complicated geotechnical and site features. For this purpose, four different and common methods of excavation support including tangent piles with anchorage, a deep soil mixing system with anchorage, tangent piles with struts, and a deep mixing system with struts were examined. The results clearly showed that tangent piles with struts gave the best results due to the rigid-like behavior of its components.

  21. PROMOTION OF ICT UTILIZATION BY ELECTRIC RESISTIVITY MANAGEMENT IN FLUIDIZATION TREATMENT PROCESS FOR GROUND IMPROVEMENT Download Article

    Yasuhide Mochida and Indra Hardi
    • Article Type: Research Article
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    • Pages (164-171)
    • No of Download = 383

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    This research introduced a new method for monitoring the quality of a ground improvement body by measuring the electrical resistivity of the body using an ICT device attached to the bucket mixer. This method shows engineers the unevenness of the electrical resistivity of the ground improvement body, which indicates imperfections in the mixing process or inconsistency of the compound within the ground improvement body. The monitoring is intended to perform real-time two-dimensional cross-section observation of the ground improvement body. The experiment yielded results enabling engineers to observe the mixing condition of the cement–soil mixture within the ground improvement body by monitoring the level of unevenness of the electrical resistivity of the body, and provides a very accurate quality control process. Quality assurance using wet grab sampling was performed and a uniaxial compressive strength test was conducted and the experimental results showed that the compressive strength of the ground improvement cement–soil mixture at any curing age could be predicted. The quality control and quality assurance method introduced in this research could minimize uncertain judgments in the current methods.

  22. DEVELOPMENT AND CHARACTERIZATION OF A COMPOSITE MATERIAL REINFORCED BY PLASTIC WASTE: APPLICATION IN THE CONSTRUCTION SECTOR Download Article

    Youssef Halimi, Manal Inchaouh, Souad Zyade and Mohamed Tahiri
    • Article Type: Research Article
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    • Pages (172-178)
    • No of Download = 170

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    Waste reuse is subject to an increasing amount of research aimed at reducing the negative impact of such material on the environment. This study explores the possibility of using plastic waste as reinforcement in composite materials. A family of materials was developed using an unsaturated polyester resin (UPR) organic matrix and various mineral fillers (marble powder, expanded perlite, sand, etc.), potentially allowing their use in wall and floor coverings and as raw materials in the manufacture of traditional ceramic tables. Selected mechanical properties of these materials were verified, including flexural strength, tensile strength, and density. The results demonstrate the role of reinforcement in oriented fibers or matt fabric in improving the mechanical properties of the materials. Flexural strength is improved via reinforcement in the form of random or woven plastic fibers (32.44 MPa). However, the use of expanded perlite as a filler results in a lower mechanical strength (31.16 MPa) than marble powder or sand because of its friability.

  23. THE BEHAVIOR OF CARBON FIBER REINFORCED POLYMER (CFRP) STRENGTHENED BEAMS UNDER A MARINE ENVIRONMENT Download Article

    Hamed Fazli, Airil Yasreen Mohd Yassin, Nasir Shafiq and Teo Wee
    • Article Type: Research Article
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    • Pages (179-184)
    • No of Download = 311

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    Marine concrete structures are subjected to a harsh environment and potential climate change variables. Deterioration of the structure demands drastic measures for repair and rehabilitation. Advanced composite materials exhibit unique advantages compared to conventional construction materials. Over the years, carbon fiber reinforced polymer (CFRP) composite material has been used widely for the repair and rehabilitation of structures. Many studies have been conducted on the performance of FRP flexural strengthened reinforced concrete (RC) members. Still, experimental studies investigating the performance of shear strengthening under real environmental conditions are lacking. This paper helps fill this gap because it is an experimental investigation of the behavior of CFRP shear strengthened RC beams under a marine environment. Specimens were exposed to cyclic (wet/dry) and full exposure to the elements for a 3-month period. Six strengthened beams and one unstrengthened beam were tested; the tested control beam failed due to a diagonal-tension crack. The increase in the concrete shear capacity of the strengthened specimens was in the range of 14–18% compared to the control beam. Thus, the results lead to the conclusion that CFRP strengthening increases the shear capacity of specimens considerably.

  24. TIME REVERSE MODELING OF HYDROCARBON DETECTION FOR PASSIVE SEISMIC SOURCE LOCALIZATION: A CASE STUDY OF SYNTHETICS AND REAL DATA FROM THE SOUTH SUMATRA BASIN, INDONESIA Download Article

    Abdul Haris, Stevanus Parlindungan Silaban, Agus Riyanto, Reza Syahputra, Sri Mardiyati, and Adriansyah
    • Article Type: Research Article
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    • Pages (185-190)
    • No of Download = 488

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    Subsurface passive seismic source localization, which is associated with hydrocarbon indication, has become an important tool for passive seismic data modeling. A time-reverse modeling (TRM) algorithm, which was applied to passive seismic data, has been developed and implemented to locate passive seismic sources by using an acoustic finite difference technique. By performing TRM, the recorded passive seismic amplitudes can be focused at their source depth, even though the focused point cannot be warranted as a source point. This paper aims to verify the ability of the developed TRM algorithm in localizing the passive seismic source associated with reservoir depth by means the possible movement of fluid. TRM was applied to synthetic and recorded passive seismic data from a gas reservoir area in the South Sumatra Basin. Synthetic passive seismic data were generated within a two-dimensional velocity model and calculated by using a finite difference algorithm simulating acoustic low-frequency wave propagation. TRM application to the synthetic data showed that passive seismic sources can be properly located in the same position as the original source. In addition, our application to the real passive seismic data sets showed that the passive seismic source is distributed randomly in the depth range of 700 m up to 1500 m, which was represented by high particle velocities.

  25. PRELIMINARY STUDY OF THE COMPRESSIBILITY OF MUNICIPAL SOLID WASTE IN INDONESIAN LANDFILL Download Article

    Febrian Hadinata, Enri Damanhuri and Benno Rahardyan
    • Article Type: Research Article
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    • Pages (191-197)
    • No of Download = 344

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    The lack of studies on the compressibility of Municipal Solid Waste (MSW) increase the uncertainty in the design and monitoring of the landfill settlement in Indonesia. This study aims to assess the compressibility of MSW in Indonesian landfill. Compression cell was made with a diameter and height of the mold at 350- and 500 mm. Compression test performed with the initial pressure of 2.04 kPa, and was increased every 24 hours, with the constant addition of 2.04 kPa, until reached a pressure of 10.20 kPa. Test performed on; paper waste with medium density (PaperMD), paper waste with high density (PaperHD) and compost with medium density (CompostMD). For PaperMD and PaperHD, moisture content of the sample was reduced by 4.45% and 1.39% (% of wet weight), whereas in CompostMD, the moisture content of the samples did not change. End of immediate compression (εEOI) detected after 6 hours for PaperMD, and 4 hours for PaperHD and CompostMD. Immediate compression ratio (Cc’) obtained at 0.2949, 0.0696 and 0.0932, each for PaperMD, PaperHD and CompostMD. While, secondary compression ratio (Cα) for PaperMD, PaperHD and CompostMD, respectively - each 0.0211, 0.0056 and 0.0060. The bulk density of the sample at the end of the test for PaperMD and CompostMD, respectively increased by 20.12% and 6.70%, while the bulk density at PaperHD was not increased. From this study, it was shown that the compressibility of the waste sample is inversely proportional to the initial density, and directly proportional to the ability to drain the leachate.

  26. CORROSION DAMAGE MEASUREMENT ON REINFORCED CONCRETE BY IMPRESSED VOLTAGE TECHNIQUE AND GRAVIMETRIC METHOD Download Article

    Emel Ken Benito, Marish S. Madlangbayan, Nimfa Maren S. Tabucal, Marloe B. Sundo, and Perlie P. Velasco
    • Article Type: Research Article
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    • Pages (198-205)
    • No of Download = 309

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    This study investigated the effect of sea water on the corrosion behavior of reinforcing steel in concrete. A 3% sodium chloride solution was used to simulate sea water. The solution was used as mixing water as well as immersion media. Combinations of mixing and immersion media considered in this study were normal-normal water (NN), normal-sea water (NS), seawater-normal water (SN), and seawater-seawater (SS). Corrosion measurement used were Impressed Voltage Test (IVT) and gravimetric method. Results showed that corrosion current curves, gravimetric mass loss, the average and maximum current passed are severe in SS but negligible in NN. The difference between NS and SN, however, is not well defined but was shown to differ in terms of corrosion current behavior before and after cracking. Incorporating chloride in the mix, regardless of its environment, was found to cause rapid crack development in concrete. Statistical analysis suggested that the presence of chloride had no influence on the outcome of percent mass loss with respect to the control sample except in SS combination.

  27. SOLUTION OF RESERVOIRS' SILTATION PROBLEM FOR HYDROPOWER DEVELOPMENT AND COASTAL PROTECTION Download Article

    Lia Matchavariani, Giorgi Metreveli, Lamzira Lagidze, Davit Svanadze and Zaza Gulashvili
    • Article Type: Research Article
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    • Pages (206-212)
    • No of Download = 265

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    Georgia, as a seaside mountain country, faces three opposing issues: hydropower development, coastal protection, and flooding risks for riparian settlements and infrastructure. Present climate change will even more strengthen processes of beach abrasions. For study of silting prisms formation process and forecasting of the equilibrium channel on it, field natural experiment has been carried out on the small mountain rivers. The experiment showed that approximately for a year silting prism on some rivers closely reached its limited size and the equilibrium channel was formed. The silting prism in the tributaries, forms the sediment train that extended till the boundary of the top water level in the river. Length of train (L) is a function of the maximum flow discharge (QM), the deposit of runoff (R), diameter of bottom sediment (d) and initial inclination of riverbed (I). With the purpose of harmonious decision of all problems, eroded beaches periodically should be artificially filled by the river sediment, accumulated in the reservoirs. It’s necessary to organize a system of the quarries in reservoirs.

  28. THE INFLUENCE OF CIRCULAR PROCESSES ON CHANGES IN PRECIPITATION IN THE SCOPE OF CLIMATE CHANGE Download Article

    Lamzira Lagidze, Lia Matchavariani and Nino Paichadze
    • Article Type: Research Article
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    • Pages (213-219)
    • No of Download = 269

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    Global climate change is one of the main problems in the world along with terrorism and poverty. Samtskhe-javakheti region, located in the south of Georgia, is very different from other regions of the country in terms of climate conditionings which is mainly due to local circular processes. Absolute altitude of Samtskhe-Javakheti varies in the 900-3300 m range. It is surrounded by high ridges. Meridian disposition of mentioned ridges weakens the impact of large-scale atmospheric circulation processes developed in the territory of the South Caucasus and significantly strengthens the influence of local complex orographic factors (tablelands, plateaus, basins) that has considerable effect on the cloud regime. Data used in the study is mainly based on observations on atmospheric precipitation (key indicators of precipitation, their monthly and annual amounts), obtained from the following (formerly existing and currently acting in Samtskhe-Javakheti) meteorological stations and weather shelters, namely: Akhalkalaki (1967-2006), Akhaltsikhe (1971-2010) and Paravani (1967-2006). Statistical, climatological and graphical analyses of multi-year (40 year period) meteorological data is used for research. Based on analyses of data, obtained for Samtskhe-Javakheti region, observed for the 10 year periods, a sharp change of monthly and annual amounts (the increase, as well as a reduction in precipitations), was observed.

  29. DECISION MAKING ON THE OPTIMISED CHOICE OF PNEUMATIC FORMWORK TEXTILE FOR FOAM-FILLED STRUCTURAL COMPOSITE PANELS Download Article

    Saeed Nemati, Maria Rashidi and Bijan Samali
    • Article Type: Research Article
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    • Pages (220-228)
    • No of Download = 302

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    The selection of an appropriate formwork system not only affects the entire construction duration and cost, but also affects subsequent construction activities such as electrical, mechanical, and finishing work. The current intuitive judgment approach in the selection of fabric formwork systems cannot assure an optimal and consistent result. This paper introduces a decision-making method for selection of the most appropriate pneumatic fabric formwork for foam-filled structural panels in rapidly assembled buildings (RABs) that will be used in semi-permanent housing such as post disaster sheltering. First, using a questionnaire survey, six most effective criteria for a suitable pneumatic fabric formwork; permeability, strength, relative cost, durability, sew-ability, and aesthetics are identified. Some experimental tests were conducted to determine the selection indicators for the criteria like durability and strength for each candidate. Then a value matrix for these factors has been defined and calculated, and the best pneumatic formwork candidate for foam-filled structural composite panels is selected from a list of seven potential candidates, using Analytical Hierarchy Process (AHP).

  30. LATERAL LOAD CAPACITY OF STEEL TRUSS COUPLING BEAM Download Article

    Nursiah Chairunnisa, Iman Satyarno, Muslikh and Akhmad Aminullah
    • Article Type: Research Article
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    • Pages (229-236)
    • No of Download = 331

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    The utilizing of steel truss coupling beam is one of an alternative for coupling beam in coupled shearwall. This paper presents an experimental study of steel truss coupling beam with span to depth ratios of 1.78 that tested under lateral cyclic loading at the laboratory. The objective of this research is to study the behaviour of steel truss coupling beam in coupled shearwall. The specimen are designed considering several factors such as span to depth ratio, strength of material, the dimension of double steel angle profile as horizontal members and steel angle profile as diagonal members. It has been shown from the test that the strength capacity of steel truss coupling beam specimens can not reach ultimate load because of inelastic buckling. Experimental results show that steel truss coupling beam can have fairly well behaviour under cyclic loading. By enlarging the dimension of horizontal members and diagonal members without increasing the thickness of profile , the strength capacity of all coupling beam specimen will have different behaviour. The result shows that the specimen with larger dimension of profile exhibits slightly raising of strength capacity than specimen with smaller dimension. The envelope curve decrease gradually which represent the specimens have well performance in terms of dissipation energy. More over, increasing appropriate dimension of diagonal and horizontal members for steel truss coupling beam with shearwalls can determine and classify the structural performance level of structure.

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