ERE - 2011

Permanent URI for this collectionhttp://192.248.9.226/handle/123/18291

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Now showing 1 - 14 of 14

item: Conference-Full-text
Proceedings of 6th National Conference on Minerals and Innovative Thinking [Pre Text]
(Department of Earth Resources Engineering, 2011-11) Ratnayake, NP; Abeysinghe, AMKB
item: Conference-Full-text
Design of a gravity wheel for mineral transport and power generation
(Department of Earth Resources Engineering, 2011-11) Premalal, DADTR; Karunanayake, WAPC; Kodikara, NE; Razmy, SAM; Dissanayake, DMDOK; Ratnayake, NP; Abeysinghe, AMKB
The energy needs of the world Mining Industry show an exponentially increasing trend owing to greater demand. The best available reports speculate that our present oil reserves will last for 40 years at most; therefore, efforts worldwide are directed towards identifying and utilizing new energy sources. Renewable energy development receives high priority among them. However, investing in new technology developments for renewable energy is time and money consuming. The main objective of the study was to adopt the Gravity Wheel concept based on the parameters given in the BuzzSaw Gravity Wheel Design of 1909, in order to develop a working model for mineral transport and power generation. The SolidWorks CAD software was used for motion study. Mathematical modelling was in favour of the continuous motion of the Gravity Wheel design. The design promises to have significant economical benefits for the mining industry. Additional benefits are also apparent for the off-grid power generation industry as well.
item: Conference-Full-text
Identifying phlogopite mica mineralization in the area around Rathnapura and suggesting suitable mining methods for sustainable exploitation
(Department of Earth Resources Engineering, 2011-11) Sashikala, JRM; Nishshanka, NAC; Karunarathna, AWKN; Anuradha, HWL; Weerawarnakula, S; Abeysinghe, AMKB; Ratnayake, NP; Abeysinghe, AMKB
Investigation carried out in the area around Rathnapura shows occurrence of economically valuable phlogopite mica mineralization in the area. Such deposits are concentrated in Hindurangala, Palkumbura, Pathagammana, Yakodiyadeniya, Thambandeniya and Kosgala. Although historical data show systematic underground mining has been carried out in some places, present mining activities are restricted to very small scale pits dug haphazardly. Vein thickness of the phlogopite mica varies from 2 cm - 1 m and extends in N 35°- 50° W direction. They generally follow the foliation pattern of the metamorphic country rocks and three major mineralization zones extending over 10 km have been found in the area. In some locations veins follow joint directions of the area. Variation in physical properties such as colour, expansion and permanent colour changes due to heat are found in the same mineralized zone in different locations.
item: Conference-Full-text
Designing and fabrication of a low cost magnetic separator for beach sand separation
(Department of Earth Resources Engineering, 2011) Hettiwatte, MC; Siyanath, HAN; Amalan, K; Rohitha, LPS; Ratnayake, NP; Abeysinghe, AMKB
The heavy mineral deposits of Sri Lanka are widely spread over the coastal area. The mining industry is looking forward for an effective method for heavy mineral separation with the low cost equipments, which suit the local environment requirements to reduce the overheads. The major deposit at Pulmoddai, Trincomalee is a well known Ulmenite deposit in Sri Lanka. The state company is currently engaged in processing using imported separators, specifically magnetic separators for ore dressing. But they are expensive and also difficult in operating, due to their outdated mechanism. In this context, the research project was launched to design and fabricate a low cost magnetic separator for beach sand separation. Through literature studies, an effort was made to add new features with innovative ideas to suit the purpose of the design. A prototype was fabricated in laboratory scale. The model was fabricated with a low cost in the laboratory is light weight, more portable, easier to assemble & dismantle. Future modifications are also possible with variable parameters. The separator was optimized for beach sand separation.
item: Conference-Full-text
Developing a hydrogeological model for Aruwakkalu limestone mine, Puttalam
(Department of Earth Resources Engineering, 2011-11) Dayarathna, EAC; Pethum, LLDI; Sunanda, DJ; Wedisinghe, WMCC; Dassanayake, ABN; Wickrama, MADMG; Ratnayake, NP; Abeysinghe, AMKB
A hydrogeological model has been developed for the Aruwakkalu limestone mine to study the behaviour of groundwater flow, associate with specific problems within the mine, in this research. Groundwater flow model was constructed using Visual MODFLOW 3D Finite difference method. Five distinct types of material layers were identified for material property designation in the study area of the mine by using the borehole data report, which was completed in year 2008. The mine is mainly bounded by two water bodies; Puttalam lagoon and Kala Oya. Existing hydrogeology related data and the results of several field tests were used to develop the groundwater model initially with a conceptual model. Utilizing hydrogeological data gained from field works; specially the aquifer parameters gained from pumping tests, the model was developed and calibrated for steady state conditions. According to the model simulation, groundwater flow is mainly towards the west direction and it simulates sea water intrusions in some locations. Dewatering feasibility and cost associated with groundwater movement of the mine can be evaluated using the developed model by conducting predictive simulations.
item: Conference-Full-text
Instrumentation and monitoring of Mahawewa landslide off Walapane
(Department of Earth Resources Engineering, 2011-11) Idirimanna, IAND; Perera, KAC; Bandara, KMT; Kumara, WGBT; Indrathilake, HML; Premasiri, HMR; Weerawarnakula, SW; Abeysinghe, AMKB; Ratnayake, NP; Abeysinghe, AMKB
The instability of the slope area at Mahawewa, Walapane has been identified as a major threat to the people and properties of the vicinity since 1986. Therefore, National Building Research Organization has started a project of monitoring and stabilization of the slope, cooperating with the Japan International Cooperation Agency in 2010. Main involvement of this study was to do the monitoring part. It is mainly based on analysis of un-stabilization parameters of the area which measured using five instruments. That is horizontal movement at sub surface using Inclinometer, fluctuation of ground water level using Piezometers, characteristics of slip surfaces using Strain Gauges, movement of the surface using Extensometers and rainfall using Rain Gauges. In addition drill log data of the site, visual information of cracks generated and springs available were also used. Global Positioning System survey was carried out for preparation of a map in this particular area. Finally, according to the results and conclusions gained from monitoring of the landslide, a suitable mitigation method was proposed.
item: Conference-Full-text
Coastal problems associated with Southern Colombo Harbour expansion project
(Department of Earth Resources Engineering, 2011-11) Nawarathna, NMIB; Jeevakan, T; Ranatunga, RPUM; Jayasena, JHDJ; Ratnayaka, NP; Ratnayake, NP; Abeysinghe, AMKB
Colombo is the major commercial harbour in Sri Lanka and the government has started to expand this harbour to increase its capacity. Therefore, a breakwater has started to build perpendicular to the shoreline. Due to these types of offshore structures wave patterns as well as current patterns changes to a large extent, leading to detrimental effects on the coastal beaches on either side of the harbour. In this study, we are planning to understand coastal effects due to the harbour expansion by studying 8 transects selected from each side of the harbour and measuring beach width, profile changes and grain size variation at mean sea level at monthly interval. This information along with previous shoreline data collected from the Survey department of Sri Lanka can be used to understand the coastal sediment dynamics including the erosion and deposition characters in the nearby beaches.
item: Conference-Full-text
Optimization of drainage network to minimize urban floods using remote sensing and GIS techniques
(Department of Earth Resources Engineering, 2011-11) Nadeeka, PM; Kumari, MADN; Abeysinghe, AMKB; Chaminda, SP; Premasiri, HMR; Ratnayake, NP; Abeysinghe, AMKB
The frequency of the occurrence of disasters is increasing day by day. Urban flooding has become one of severe problems faced by Sri Lanka seasonally leading for various social and environmental interruptions. With the increasing of the occurrence it has become a necessity to find a proper solution to mainly focuses to optimize the drainage network in Panadura urban council area, Sri Lanka to minimize the urban flood hazard susceptibility using Remote Sensing (RS) and Geographical Information System (GIS) techniques. Light Detection And Ranging (LiDAR) Digital Elevation Model (DEM) was utilized to delineate requisite drainage and mini water catchments using Environmental Systems Research Institute (ESRI) Arc Hydro Model. Prior to LiDAR DEM processing an accuracy assessment was performed with respect to the ground truth elevation measured by Total Station and GPS surveys. Current available drainage system in the area was assessed in two ways as alignment and capacity for large water volumes in heavy rainfalls with respect to the delineated natural drainage system. By performing the comparison successfully, highly flood vulnerable locations in the current drainage system were identified. Finally adjustments to the current drainage network and new drainage paths were proposed.
item: Conference-Full-text
Parameter estimation of pollutant removal for subsurface horizontal flow constructed wetlands treating greywater
(Department of Earth Resources Engineering, 2011-11) Wijesiri, MKBS; Jayasooriya, VM; Karunarathne, S; Ratnayake, NP; Abeysinghe, AMKB
Treatment efficiencies of pilot scale constructed wetland treating greywater from a staff canteen of the University of Moratuwa was studied to estimate the temperature dependent reaction rate constants of specific pollutant removal mechanisms. The treatment cell, constructed below the ground level is four meter (4.0 m) long 1.8 m wide (at the top level). The cell is divided longitudinally at the centre while vertical baffles are provided at approximately 590 mm intervals, running through the entire vertical depth (0.75 m) of the wetland cell with an opening of 270 - 380 mm. Considering the middle separation, the effective average width and the length of the treatment cell is 0.75 m and 8.0 m, respectively. The bed is vegetated with cat tail (Typha Latifolia) planted at approximately 0.75 m intervals. The study estimates the design parameters pertaining to local conditions to optimize the design considerations and sizing requirements using both first order and Monod type models. The estimated parameters can effectively be applied in sizing constructed wetlands in tropical climatic conditions. The results show that the surface area of SHF CWs can be reduced by 26% by utilizing the newly estimated parameters from the current study.
item: Conference-Full-text
Optimization of blasting geometry for different rock types
(Department of Earth Resources Engineering, 2011-11) Sameera, JDAM; De Silva, HCN; Vijithan, K; Wamasooriya, WMNT; Chminda, SP; Abeysinghe, AMKB; Hemalal, PVA; Ratnayake, NP; Abeysinghe, AMKB
Sri Lankan quarries observe their own blasting parameters and standards mainly based on experience gained over the years. Some of them are not the optimum values, due to the fact most of the quarries economical problems. In this research an attempt has been made to find the optimum burden and spacing for different rocks in Sri Lanka using a graphical relationship with spacing or burden vs cost per unit production while keeping drilling parameters such as drill hole diameter, drill hole depth, angle of drilling, bench height and explosive quantity per drill hole constant. Optimum burden and spacing means the burden or spacing which gives production with lower cost with the ground vibration and air blast at permissible limits. To determine the ground vibration and the air blast over pressure of tire optimum values at particular distances, a neural network was computed by training the data we gathered.
item: Conference-Full-text
Performance evaluation of emulsion/water-gel explosives and comparison with dynamite in Sri Lankan quarrying practices
(Department of Earth Resources Engineering, 2011-11) Sanjeewa, KWD; Fernando, PLD; Zoysa, AUD; Ramees, AM; Hemalal, PVA; Dharmaratne, PGR; Ratnayake, NP; Amarasinghe, AMKB
At present, Dynamite is currently manufactured only in a few countries as a commercial explosive due to its high cost hazardousness. Therefore import and supply do not match the demand patterns which inevitably result in considerable inconvenience to the quarry industrialists to certain degree affecting the development of this industry which has a direct bearing on the country's infrastructure development. Consequently, there is great necessity to manufacture high quality explosive of low cost and less hazardousness as a substitute for Dynamite. By using Magnesium/micro glass bubbles/ Aluminium, instead of the main sensitizer (Nitro Glycerin) of Dynamite, Slurry explosives (Water-Gel) are manufactured under the similar process as a powerful explosive. In this instance, the industrialists have been compelled to use the low cost but almost untested explosive as a substitute. Research so far carried out only show that the product is substandard which dictates further the investigation.
item: Conference-Full-text
Minimization of secondary fragmentation with a view to enhancing the blasting economics
(Department of Earth Resources Engineering, 2011-11) Piomathusoothanan, F; Batugampala, BBMP; Harischandra, YCK; Amaranath, RMSPK; Hemalal, PVA; Dharmaratne, PGR; Ratnayake, NP; Abeysinghe, AMKB
Construction materials have a huge demand and become an expensive commodity due to limited quarry activity. Further Research and Development (R and D) is very important in quarry industry in order to minimize the cost of quarry products in Sri Lanka. Cost of secondary fragmentation is a significant factor in this regard. This research is aimed exploring the methods at reducing the fragmentation cost effectively. Formation of the boulders mainly depends on the geological diversity, bench parameters and varying powder factor. Site geology is a natural factor that cannot be adjusted but the bench parameters and the powder factor can be changed over wide range to reduce the boulder formation. Three consecutive blasts were designed by the project team. The bench parameters and powder factor were determined to control the formation of the boulders.The plan views of the blasted muck piles were photographed to analyse the particle size distribution of the muck pile.
item: Conference-Full-text
Cost reduction of quality controlling in metal quarrying
(Department of Earth Resources Engineering, 2011-11) Basnayaka, LR; Samarathunga, SPGN; Susantha, TKJ; Nawaneethan, M; Wickrama, MADMG; Samaradiwakara, GVI; Dassanayake, ABN; Ratnayake, NP; Abeysinghe, AMKB
Quality controlling of aggregates is a major concern in aggregate industry. Cost of quality controlling can be minimized via finding correlations between different test on aggregates and rocks. Los Angeles abrasion value test, Aggregate impact value test, Uni-axial compressive strength test, Point load index and Schmidt hammer rebound value test were performed on a total of 22 gneissic metamorphic rock samples, which were collected from selected two quarries in Meepe and Nebada areas of Sri Lanka to investigate correlations between these test parameters. Correlations were developed between each parameter to reduce the cost of quality controlling by means of regression analysis. The study found a strong correlation between Loss Angeles abrasion value test and Aggregate impact value test. By analysing correlation between tests, mineralogy and rock properties validity of this correlation can be proved for common application
item: Conference-Full-text
Suitability of light coloured silicate metamorphic rocks of Sri Lanka in construction industry
(Department of Earth Resources Engineering, 2011-11) Karunathilaka, JKWPC; Karunarathne, S; Rohitha, LPS; Ratnayake, NP; Abeysinghe, AMKB
Conventionally, in the local construction industry, darker coloured (melanocratic) rocks are preferred over light coloured (leucocratic) rocks without proper scientific reasoning. Hence, the objective of the study is to assess the suitability of leucocratic rock types in construction applications as raw materials by analyzing desirable properties. Rock samples ranging from dark colour to light colour collected by visual inspection. The degree of light colouredness was determined through a microscopic analysis. Unconfined Compressive Strength (UCS) test, Point Load Index (PLI) test, Los Angeles Abrasion Test (LAAV) and Aggregate Impact Value Test (AIV) were carried out on samples prepared according to the standard methods. Concrete mixtures made out of different aggregates with varying leucocratic contents were also tested for strength and rate of strength gain by concrete cube testing. Test results were analyzed with respect to the degree of light colouredness to identify the desirable aggregate properties to be used in construction industry.

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