Articles

  1. MODELING OF EVAPORATION PROCESSES UNDER THE GROUND Download Article

    A. Kobayashi, B. Liu, Y. Tsukada and M. Chijimatsu
    • Article Type: Research Article
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    • Pages (2403-2409)
    • No of Download = 796

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    The vaporization process is modeled by incorporating the relation between pressure and enthalpy into the numerical simulation code for the coupled thermal, hydraulic and mechanical phenomena under the ground. The boundary between superheated steam and two-phase of steam and water was modeled by the previous study. On the other hand, the boundary between compressed water and two-phase of steam and liquid is modeled by the deduced equation with pressure and enthalpy in this study. Temperature is selected to be the unknown variable in the model. The enthalpy is estimated from the pressure and temperature, and then the situation of phase is examined. As an example, the situation about the disposal of the waste generating heat to 300˚C is simulated by the simple 2-D and detail 1-D models.

  2. NVESTIGATION OF THE HYDRAULIC EFFICIENCY OF SAND - NATURAL EXPANSIVE CLAY MIXTURES Download Article

    Abdullah A. Shaker and Tamer Y. Elkady
    • Article Type: Research Article
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    • Pages (2410-2415)
    • No of Download = 802

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    The aim of this study is to evaluate the hydraulic performance of a sand-natural expansive clay mixture in comparison with sand-bentonite mixture. Natural expansive clay used in this study was obtained from Al-Qatif region, Saudi Arabia. The saturated hydraulic conductivity was evaluated for different mixtures of sand-Al Qatif clay with clay contents ranging from 10% to 60% clay. Similarly, the saturated hydraulic conductivity of sand-bentonite mixtures with different bentonite contents (0%, 5%, 10% and 20%) was also evaluated. All hydraulic conductivity tests were performed under different confining pressures. Test results revealed that sand-Al-Qatif clay mixtures can perform adequately as a hydraulic barrier; however, with Al-Qatif clay contents greater than that used for sand-bentonite mixtures. This is attributed to difference between clay mineralogy between Al-Qatif clay and bentonite. In addition a quantitative approach is proposed to assess the hydraulic conductivity of sand-Al-Qatif clay mixtures in comparison to that for sand-bentonite mixtures. Finally, soil fabric of mixtures was examined using scanning electron microscope (SEM) technique to observe differences in fabric between sand-Al-Qatif clay and sand-bentonite mixtures. 

  3. CHANGES OF CHLOROPHYLL-A, BACTERIOCHLOROPHYLL-C AND DOC BEFORE AND AFTER REVETMENT WORK IN LAKE FUKAMI-IKE, JAPAN Download Article

    Megumi Nobori, Hiromi Suda, Maki Oyagi, Akiko Yokoyama and Akihiko Yagi
    • Article Type: Research Article
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    • Pages (2416-2421)
    • No of Download = 702

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    Lake Fukami-ike is a small eutrophic lake of 2.1 ha with a maximum depth of 7.70 m in central Japan and water stratified from March to October. Anoxic conditions prevailed below 4-5 m depth from April to October and a photosynthetic green sulfur bacteria (BChl.c) accumulated in the hypolimnion. In Lake Fukami-ike, the revetment work was environment maintenance for activation of the town in 1992, and the water quality of this lake was considered to be clean. However, fluctuation in the transparency became larger than before. Data before and after revetment work (1992) was studied. The DOC amount of stagnation period was increased after revetment work more than before it, and the difference between maximum and minimum values also increased. Chl.a was increased in both water concentration and the water column. BChl.c had been confirmed to increase concentration and biomass. The inflow of domestic wastewater did not stop; nutrients increased and Chl.a, BChl.c and the DOC also increased. Such a phenomenon is considered to be one of the factors in the variation in the transparency increase

  4. OPTIMAL DESIGN OF RAIN GAUGE NETWORK IN JOHOR BY USING GEOSTATISTICS AND PARTICLE SWARM OPTIMIZATION Download Article

    Mohd Khairul Bazli Mohd Aziz, Fadhilah Yusof, Zalina Mohd Daud, Zulkifli Yusop and Mohammad Afif Kasno
    • Article Type: Research Article
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    • Pages (2422-2428)
    • No of Download = 1098

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    This study proposes particle swarm optimization (PSO) approach to determine the optimal number and locations for the optimal rain gauge network in Johor state. The existing network of 84 rain gauges in Johor is also restructured into new locations by using daily rainfall, humidity, solar radiation, temperature and wind speed data collected during the monsoon season (November – February) of 1975 until 2008. This study used the combination of geostatistics method (variance-reduction method) and particle swarm optimization as the algorithm of optimization during the restructured proses. The numerical result shows that the new rain gauge location provides minimum value of estimated variance. This shows that the proposed method can serve as an analysis tool for a decision making to assist hydrologist in the selection of prime sites for the installation of rain gauge stations.

  5. ANALYSIS OF EVACUATION BEHAVIORS IN DIFFERENT AREAS BEFORE AND AFTER THE GREAT EAST JAPAN EARTHQUAKE Download Article

    Tetsuo Morita, Shinya Tsukada and Akira Yuzawa
    • Article Type: Research Article
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    • Pages (2429-2434)
    • No of Download = 767

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    This study aims to obtain the insights necessary for future disaster prevention planning and management in Japan. To this end, a questionnaire survey on evacuation behaviors was administered to the residents of Yamada-machi in Iwate Prefecture and Ishinomaki-shi in Miyagi Prefecture, which had been stricken by the Great East Japan Earthquake. The obtained data were analyzed on the basis of the regional differences in said behaviors. The analytical results are summarized as follows. (1) Prevention measures, such as earthquake drills and occasional discussions regarding earthquakes, tended to be implemented in areas facing the Rias coast before the Great Earthquake occurred. (2) The interval between the occurrence of the earthquake and the initiation of evacuation was shorter in the regions fronting the Rias coast and in those located along a coastline than in areas situated on a plain and along a river. (3) Residents of the regions facing the Rias coast and the areas located along a river tended to evacuate by foot, whereas people living in other areas favored evacuation by automobile.

  6. GROUNDWATER CONTAMINATION PLUME DELINEATION USING LOCAL SINGULARITY MAPPING TECHNIQUE Download Article

    Bithin Datta, Mahsa Amirabdollahian, Renguang Zuo and Om Prakash
    • Article Type: Research Article
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    • Pages (2435-2441)
    • No of Download = 766

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    The evaluation and remediation of contaminated aquifers requires accurate delineation of contamination plumes. Ideally a large number of observed concentration data are required to achieve an accurate delineation of the contamination plume. However, in practice due to the budgetary constraints, the contamination in groundwater resources is detected by limited number of arbitrary located or predesigned contamination monitoring wells. Therefore, a technique is required to estimate the boundaries of the plume using the available sparse observation data. In this work, Local Singularity Mapping Technique is used for plume delineation. The singularity mapping technique is based on the multifractal concept. In fractal geometry a local feature is similar to the whole in terms of shape and structure. Generalized self-similarity is characterized by a power-law relationship. Using this method, singularity indices are estimated for the entire study area using sampled concentration data. According to these indices the mapped area (study area) is classified into subsets including contaminated and clean areas. The boundaries between these two subset areas can be identified as the contamination plume edge. The performance of this method is evaluated in an illustrative contaminated study area to demonstrate the potential applicability of the proposed methodology. The singularity indices can be utilized to locate potential contamination sources as well as plume boundaries. The evaluation results demonstrated that the contamination plumes can be relatively accurately delineated using the fractal geometry.

  7. GENETIC DIVERSITY OF RESTORED ENDANGERED SPECIES, PENTHORUM CHINENSE IN THE RIVERBED Download Article

    Michiko Masuda and Fumitake Nishimura
    • Article Type: Research Article
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    • Pages (2442-2446)
    • No of Download = 454

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    The Ministry of Land, Infrastructure and Transport has done the business of digging on the river road to increase the flowing quantity of Ibi River every year since 2000. It is reported to the dug region the Penthorum chinense populations which is the threatened species the restored in 2001. Digging is done from 2000 to 2010 every year. Therefore, we investigated P. chinesne population of which extent to which region grew. As a result, it was shown some the growth of the plant of 200 individuals in the 2002 digging region, 4000 individuals in the 2001 digging region and 1000 individuals in the 2000 digging region, and so on. Though it is thought that the population formed in 2000 is seed bank origin, whether the populations formed in 2001 and later the burial seed origin or formed with the seed of an existing population, it is uncertain. Then we sampled 8 populations of the species form these areas, and studied them for allelic variation at 16 enzyme loci. There was no significant correlation between the actual population size and genetic diversity parameters, suggesting that the effective population size was very small even for the large populations. However, population that restored at the riverbed and population that approved on the embankment were able to distinguish obviously in the populations that had been approved in 2002. As for the population approved to the embankment, it was shown that genetic variation was very high in the population approved to the riverbed thought it was hardly admitted.

  8. ENHANCING THE ENGINEERING PROPERTIES OF EXPANSIVE SOIL USING BAGASSE ASH AND HYDRATED LIME Download Article

    Liet Chi Dang, Hayder Hasan, Behzad Fatahi, Robert Jones and Hadi Khabbaz
    • Article Type: Research Article
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    • Pages (2447-2454)
    • No of Download = 2006

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    The main objective of this paper is to investigate the influence of hydrated lime and bagasse ash on engineering properties of expansive soil obtained from an array of laboratory tests. Bagasse ash is a readily available waste by-product of the sugar-cane refining industry posing risks to environment. Bagasse ash is considered in this investigation in order to evaluate the potential benefits of its pozzolanic material for stabilisation of expansive soil. The preparation of stabilised soil specimens was conducted by changing the bagasse ash contents from 0 to 25% by dry weight of expansive soil along with an increase in hydrated lime. The bearing capacity and shrinkage properties of stabilised expansive soil were examined through a series of experimental tests including linear shrinkage and California bearing ratio (CBR) after various curing periods of 3, 7 and 28 days. The results reveal that the additions of hydrated lime and bagasse ash improved the strength and bearing capacity of stabilised expansive soil remarkably, and meanwhile significantly reduced the linear shrinkage of treated expansive soil. Hence, the application of hydrated lime and bagasse ash as reinforcing material can not only enhance the engineering properties of expansive soil, but also facilitate sustainable development by using sugarcane waste by-product to improve unusable clay material in road construction.

  9. SPATIAL TSUNAMI WAVE MODELLING FOR THE SOUTH JAVA COASTAL AREA, INDONESIA Download Article

    Agus Hartoko, Muhamad Helmi, Mujahid Sukarno and Hariyadi
    • Article Type: Research Article
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    • Pages (2455-2460)
    • No of Download = 545

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    Geoposition of Indonesia that the country was surrounded by Eurasian – Australian and Pacific tectonic plate with its subduction zone (ring of fire) had experiencing very high frequency tectonic earth quake and risk of tsunami wave. The need of reliable tectonic plate earth quake and risk of tsunami spatial data base model was inevitable. The paper built numeric and spatial data base, analysis and develop tsunami modeling for three sites of south Java (Serang – west of south Java, Bantul - central and Banyuwangi - east of south Java) which were regarded as the most dense populated island. Phase one steps were built spatial database of the tectonic plate subduction zone with variable of depth, distance and ocean floor topography using ETOPO-2 USGS bathymetric data. Phase two steps including the development of tectonic plate earth quake history data base with above 6 Richter scale for the past five years. Development of numeric tsunami spatial model using MIKE-21 software (Evaluation License) with variable of tectonic plate earth quake coordinate, magnitude of 8 Richter scale and depth. Followed with detail analysis of the tsunami waves characters such as the height and travel time and direction towards coastal area, tsunami wave oscillation, time and run-up height and distance in reaching the coastal area. Phase three steps including development of spatial data base of contour Digital Elevation Model (SRTM-data), run-up model and wave height in reaching the dense population area and detail village and sub-district boundary, population, number of house and buildings, infrastructure and land use of the affected area and finally followed by escape route scenario and site-selection for possible community escape site.

  10. STRENGTHENING OF SAND CEMENTED WITH CALCIUM PHOSPHATE COMPOUNDS USING PLANT-DERIVED UREASE Download Article

    R.A.N. Dilrukshi, Jun Watanabe and Satoru Kawasaki
    • Article Type: Research Article
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    • Pages (2461-2467)
    • No of Download = 615

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    The effect of plant-derived urease enzyme to induce the precipitation of calcium phosphate compounds (CPCs) and hence, to improve the unconfined compressive strength (UCS) of sand was examined as a novel, eco-friendly ground improvement method. Initially, Toyoura sand test pieces were cemented only from CPC solution. Furthermore, another sand test pieces were cemented by different concentrations of urea, concentration fixed plant seeds extract (Watermelon) to obtain optimal cementation, and different concentrations of CPC solutions made from calcium and phosphate stock solutions. All test pieces were cured up to 28 days in an airtight container at high humidity at 25oC. The UCS tests and scanning electron microscope (SEM) observations of sand test pieces were carried out. The UCS of test pieces cemented with CPC and plant extract were significantly higher than that of test pieces cemented without plant extract and increases with time. The best ratio of Ca: P in CPC solution was 0.75 M: 1.5 M, reaching a maximum UCS of 125.6 kPa after 28 days of curing. In addition, pH concentration was measured after UCS test and it has increased with time. Results indicate that the best pH for optimal cementation is 8.0. A specific crystal structure could not be identified from SEM observations in the segments of the test pieces cemented with CPC in all cases in this study. These results suggest that the addition of plant extract to CPC significantly enhances the mechanical properties of sand.

  11. DESIGNING URBAN RIVERS TO MAXIMISE THEIR GEOMORPHIC AND ECOLOGIC DIVERSITY Download Article

    Melissa Neave1 and Scott Rayburg
    • Article Type: Research Article
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    • Pages (2468-2473)
    • No of Download = 574

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    River geomorphic complexity is vital to support abundant and diverse ecological assemblages in river environments. With the ever increasing population of global cities, and the consequent spread of urbanized land, pressures on engineers and land planners to modify and control urban rivers channels could be detrimental to their ecological diversity. This research project provides an analysis of the geomorphic complexity and heterogeneity of an urban stream. The study compares different sections of Orphan School Creek in western Sydney, Australia to investigate how channelization and/or alternations in riparian vegetation impact on geomorphic heterogeneity. The sections of Orphan School Creek examined range from freely meandering to fully concrete channelized reaches. The results of this research project clearly show that urbanization has detrimental effects on the geomorphic complexity of urban streams, due to both catchment urbanization and channelization. Through the analysis of Orphan School Creek it was concluded that channelization reduces river geomorphic complexity, with concrete channels providing little or no geomorphic complexity or diversity. However, if managed and/or designed with a view towards optimising geomorphic complexity, urban rivers can attain meaningful ecological benefits while still being controlled to prevent damage to the urban environment from flooding and/or erosion.

  12. AN EXACT DISPLACEMENT BASED FINITE ELEMENT MODEL FOR AXIALLY LOADED PILE IN ELASTO-PLASTIC SOIL Download Article

    C. Buachart, C. Hansapinyo and W. Sommanawat
    • Article Type: Research Article
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    • Pages (2474-2479)
    • No of Download = 619

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    A displacement based finite element method for analyzing axially loaded pile embedded in finite depth of elasto-plastic soil is presented. The investigation herein is conducted on the condition of shape function by which exact value may be reproduced at the nodal point regarding to a few number of element. The examined shape functions which satisfy the homogeneous governing equations in elastic and plastic soil are introduced to obtain the so-celled exact element stiffness matrix via total potential energy principle. Numerical examples of elasto-static pile, embedded in elasto-plastic Winkler foundation illustrates the accuracy of proposed element compare with conventional finite element shape functions. Axial force and displacement solutions show very good agreement with data from the available literature. Then the proposed shape functions are also used to conduct free vibration analysis of axially loaded pile embedded in elastic soil. The results from finite element modal analysis show fairly accurate compare with analytical solutions.

  13. CLAY-CEMENT ADDITIVE FOR CRUSHED ROCK BASE STABILISATION: STRENGTH PROPERTY INVESTIGATION Download Article

    Peerapong Jitsangiam, Matthew Merrin, and Sarayoot Kumlai
    • Article Type: Research Article
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    • Pages (2480-2485)
    • No of Download = 619

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    With the current base course material in Western Australia, namely hydrated cement treated crushed rock base (HCTCRB), roads using HCTCRB require excessive maintenance causing from its uncertainties. This study aims to determine specific strength properties of a potential replacement material of a clay-cement stabilized crushed rock. The findings showed that a crushed rock material with a newly developed 3% clay-cement binder, possessed unconfined compressive strengths and resilient moduli significantly greater than that of HCTCRB. The developed stress dependent equation also purports that this material admixture is still exhibiting unbound performance characteristics. A material’s ability to acquire the accompanying strength advantages of a 3% clay-cement binder, whilst still potentially resisting common failure methods such as shrinkage cracking, suggests that based on its potential performance as a base course layer in a pavement structure, clay-cement stabilized crushed rock base is considerable to be a viable base course material for Western Australia.

  14. GRADATION BAND OF SOME TYPES MATERIAL FOR RESERVOIR BASE OF POROUS PAVEMENT Download Article

    Yulvi Zaika and Ludfi Djakfar
    • Article Type: Research Article
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    • Pages (2486-2492)
    • No of Download = 950

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    Recent year, reducing of open area and the extreme rainfall are reason for the flood in some city in Indonesia. The drainage and infiltrated well were constructed in some parts of the city could not solve the problem yet. The porous pavement can be applied to reduce run off, rate and pollutants. Reservoir base or sub base is an important layer as part of structure and also temporary store rainfall water before infiltrate to the subgrade. This study assessed characteristic and gradation some types of materials as stone crush, limestone and steel slag for porous pavement and evaluate this performance based on California Bearing Ratio (CBR) and porosity. Naturally these characteristics are contrary, in which for high porosity materials will have low bearing capacity. There are 7 gradations consist of 4 gradations in coarse aggregate and 3 gradations based on Bina Marga (Indonesian Highway Agency). The result showed that CBR of stone crush is high in uniform course material gradation than limestone and steel slag. In the term of porosity, the result completely the same for all materials in which the uniform gradation give the high porosity. It makes sign the influence of hardness and gradation of material will give contribution for bearing capacity and only gradation influence to porosity. The material are suitable for reservoir layer of porous pavement for light traffic load. Gradation band is lied between Bina Marga and NAPA and AASHTO specification.

  15. STRENGTH PROPERTIES OF ROAD BASE MATERIALS BLENDED WITH WASTE LIMESTONES Download Article

    Jonathan R. Dungca and Lydia Francisca T. Dychangco
    • Article Type: Research Article
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    • Pages (2493-2498)
    • No of Download = 762

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    Most areas in the Philippines experience high road construction cost due to the limited supply of suitable materials for road embankment within economic haul distances. Considering that the country is currently having extensive infrastructure development, potential use of naturally-occuring materials such as limestones was tested resulting not only as an economic alternative to the conventional materials, but leading to an improved strength of roads. Geotechnical and morphological properties of pure and blended materials were determined characterizing the behavior of the strength of the materials as limestone blend varies. A 50% blend of limestone to conventional road base materials provided optimum strength increasing the values up to 30%, 100% and 40% for unsoaked CBR, soaked CBR and UCS, respectively.

  16. DRAINAGE SYSTEM OF PRAMBANAN TEMPLE YARD USING NO-FINE CONCRETE OF VOLCANIC ASH AND BANTAK MERAPI Download Article

    Ahmad Rifa’i, Nor Puji Lestari and Noriyuki Yasufuku
    • Article Type: Research Article
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    • Pages (2499-2505)
    • No of Download = 382

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    This paper focuses on the potential utilization of volcanic ash and coarse volcanic slag for no-fine concrete for drainage structure of Prambanan temple yard. This material produced from volcanic eruption also becomes environmental important issues as waste material if it is not effectively reduced or reused. Coarse volcanic slag is commonly known by local people as Bantak. The experimental study was conducted to determine engineering properties of no-fines concrete materials and discharge capacity of drainage system was calculated to identify the optimal dimensions of the drainage channel. In addition, a numerical analysis was carried out using SAP2000 and Plaxis to control structure stability. Based on numerical and experimental study, the utilization of no-fine concrete from volcanic ash and bantak by using certain mix design can be used as a porous drainage structure. By utilizing the eco-friendly material as structural material, the originality of the building will not be disturbed.

  17. CREEP AND RELAXATION BEHAVIOR OF HIGHLY ORGANIC SOIL Download Article

    Shoji KAMAO
    • Article Type: Research Article
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    • Pages (2506-2511)
    • No of Download = 1224

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    Because of the limited land area in Japan, many structures are built on peat and/or highly organic soft ground. . These soils are well known for exhibiting large settlement and secondary compression during and after construction. Preloading is suitable for ground improvement of peat and highly organic soil, as well as clay.
    The author has performed a series of laboratory loading and/or unloading creep tests that simulate actual preloading method for peat and silty clay which samples collected in Japan. Previously, the author reported that the characteristics of long-term creep settlement after unloading (rebound ratio, rate of secondary compression and re-settlement point) are affected by the over consolidation ratio, preloading time and plasticity index [1], [2]. In this paper, the experimental data from loading and/or unloading creep tests and stress relaxation tests are used to further explore the behavior of highly organic soil

  18. THE SPHERE DRAG RHEOMETER: A NEW INSTRUMENT FOR ANALYSING MUD AND DEBRIS FLOW MATERIALS Download Article

    Anna Maria Pellegrino, Anna Scotto di Santolo and Leonardo Schippa
    • Article Type: Research Article
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    • Pages (2512-2519)
    • No of Download = 415

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    The present study focused on novel rheometrical tool for the determination of the rheological behavior of large particle mixtures with particular interest in the application to granular materials involving in fast landslides as mud and debris flows. The main goal is the development of the Sphere Drag Rheometer (SDR), a home-made large-scale rheometer that allow to estimate the rheological properties of these mixtures considering particles up to 50 mm grain size. The SDR is composed of a sphere rigidly joined to a support that moves at constant velocity into the mixture. Compared to standard rheometer, the SDR uses much higher volume of mixtures of wider grain size distribution next to that in situ. Several pyroclastic soils collected from the source area of debris flows occurred in Campania region (Southern Italy) were analyzed. The paper reports the experimental results on fine particles mixtures, large particle mixtures, and their comparison. The experimental results on fine mixture are compared with those obtained by conventional rheometrical tools reported in previous papers.

  19. ROCK SLOPES PROCESSES AND RECOMMENDED METHODS FOR ANALYSIS Download Article

    A. K. Alzo’ubi
    • Article Type: Research Article
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    • Pages (2520-2527)
    • No of Download = 805

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    The stability of rock slopes is of great concern in many engineering projects, for example; road cuts, foundations, retaining walls, and dam excavation. Generally, rock slopes susceptible to instability could be divided into two main categories, the structurally controlled slopes, and the complex rock slopes. In the later, rock slope instability would involve intact material fracturing to allow for rupture surface to be formed. Kinematics of a landslide or the type of movement or instability associated with the landsides is one of the principal criteria for classifying a landslide. In this paper, the modes of instabilities that have been observed in the field are discussed and examples are given. The most widely used methods of analysis of rock slopes such as, limit equilibrium, finite element, discrete element; boundary elements are discussed to highlight their advantages and disadvantages. In this paper, the classification and the methods of analysis are discussed to provide researches as well as engineers with the tools required to analyze and design rock slopes. In complex rock slopes, in civil or mining engineering, hybrid numerical methods must be adapted to better understand the behavior of rock slope. In the case of simple sliding slopes, Limit Equilibrium Techniques can be easily utilized.