This study investigated the relationship between Uniaxial Compressive Strength (UCS) and slake durability index (SDI) in gneiss rocks collected from two aggregate quarry sites. The analysis revealed varying correlations between these two... more
This study investigated the relationship between Uniaxial Compressive Strength (UCS) and slake durability index (SDI) in gneiss rocks collected from two aggregate quarry sites. The analysis revealed varying correlations between these two parameters depending on the grouping and categorisation of the data. Initially, a moderate correlation was observed between experimental and estimated UCS values when considering all the data together. However, further examination of the data by dividing it into two categories based on UCS values greater than or equal to 40 MPa and less than 40 MPa yielded insightful results. Within these divided categories, a robust correlation was found between experimental and estimated UCS values for cycles two and four of SDI. Moreover, this study reveals that fresh rock samples from the quarry locations maintained a durability of over 98% through four cycles of the slake durability test. Nonetheless, these same samples exhibited decreased strength, which can be attributed to their mineral composition and internal structural arrangements of the rock samples tested. Therefore, this study incorporated complementary testing methods such as Ultrasonic Pulse Wave Velocity (UPV) and Scanning Electron Microscope/Energy Dispersive X-ray Spectroscopy (SEM/EDX). These tests served as valuable tools for validating the results and enhancing the understanding of micro-scale changes within the gneiss rock samples. The comparison of test values and the exploration of underlying factors confirmed the reliability and usefulness of UPV and SEM/EDX as supporting tools for this study. The study also recommended that the developed equations can be useful for engineers and researchers in estimating rock strength quickly and inexpensively by replacing the laborious tasks involved in traditional laboratory testing.
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This comprehensive review paper provides a detailed analysis of the extraction methods employed in the dimension stone industry. Natural rock materials used in construction, have been historically extracted using primitive techniques such... more
This comprehensive review paper provides a detailed analysis of the extraction methods employed in the dimension stone industry. Natural rock materials used in construction, have been historically extracted using primitive techniques such as thermal shock, hammer and chisel, and plug and feather. However, significant technological advancements have revolutionized the industry, leading to the widespread adoption of mechanized methods. One highly efficient technique is diamond wire cutting, which involves the utilization of diamond-engraved bits affixed to a tensioned steel wire. This method has demonstrated remarkable capabilities in minimizing waste generation and ensuring exceptional machining quality. Nonetheless, challenges such as high operating costs and wire breakage persist and require further investigation. In addition to diamond wire cutting, this review explores the utilization of circular diamond saws and frame sawing as alternative extraction methods. The geotechnical ch...
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Coal fly ash (CFA) is a highly versatile raw material that has the potential to yield multiple value-added products, including cenospheres, zeolites, carbon nanotubes, and fertiliser substrates. Despite its versatility, a majority of... more
Coal fly ash (CFA) is a highly versatile raw material that has the potential to yield multiple value-added products, including cenospheres, zeolites, carbon nanotubes, and fertiliser substrates. Despite its versatility, a majority of these components are often overlooked, and CFA is primarily used for construction. Conventional processing methods of CFA are known to pose significant environmental challenges, including the leaching of hazardous materials, emission of toxic gases, and the high energy consumption needed to extract the value-added components. Herein, we explore the potential of biometallurgical approaches as an eco-friendly alternative to conventional processing methods for the comprehensive utilisation of CFA. Our focus is on the application of different microorganisms to CFA, the domestication of microorganisms, preprocessing of CFA to facilitate effective biometallurgical processes, the use of bioreactors, and synthesis of nano silica particles. We also propose a nov...
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Beachrock is coastal sediment that has been cemented primarily by calcium carbonate within the intertidal zone in tropical and subtropical regions. Considering that beachrock has the potential to inhibit coastal erosion, we performed... more
Beachrock is coastal sediment that has been cemented primarily by calcium carbonate within the intertidal zone in tropical and subtropical regions. Considering that beachrock has the potential to inhibit coastal erosion, we performed laboratory tests to understand the formation mechanism of beachrocks in southern coastal regions of Sri Lanka. The mineralogical composition of beachrock samples were identified by FT-IR spectroscopic technique. The constituents of minerals present in the beachrocks were further confirmed by XRD analysis. Elemental concentrations of beachrock samples have been examined using WD-XRF spectrometry. The formative environment (sea water) was analyzed using EDTA titration, AAS, UV/Vis spectroscopy and Iron Chromatography. The results reveal the presence of minerals aragonite, calcite, orthoclase, quartz, albite, kaolinite and lime in the beachrocks. According to the results, there is a high probability to precipitate CaCO3 from the sea water in southern coastal regions indicating a positive formative environment for beachrocks. Hence, by appropriate regulation of the conditions could foster the development of manmade beachrocks to control the coastal erosion.
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Smartphones have become an essential companion in most of the communities. Yet, we may not be quite aware of the capabilities and services that these devices could provide. As a result, features such as location services are... more
Smartphones have become an essential companion in most of the communities. Yet, we may not be quite aware of the capabilities and services that these devices could provide. As a result, features such as location services are under-utilized and mostly used for navigation and location sharing. This study explores the limitations of embedded GPS receivers in smartphones with reference to the performance of a consumer-grade hand-held GPS device. The location coordinates obtained with the GPS unit and six smartphones on five locations over ten consecutive days revealed that over 70% of smartphone records provide the location coordinates within 0 to 10 m accuracy. Furthermore, at certain locations, over 75% of records have maintained the coordinate accuracy within 0 to 5 m. Hence, the use of smartphone location information in place of standalone GPS readings, can be recommended for moderate location accuracy requirements, such as geo-tagged data collection. Nevertheless, hand-held GPS units provide better approximations than the smartphones, for elevation readings at the studied locations. Accordingly, further investigations are recommended, to evaluate the discrepancies in elevation records, provided the ambiguities generated while recording the elevation measurements from the hand-held GPS units are minimized.
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Water in the forms of rain, snowmelt and groundwater is identified to be the major factor influencing the reduction of the stability of the slopes. The increasing trend of annual rainfall has been a major challenge to meet the production... more
Water in the forms of rain, snowmelt and groundwater is identified to be the major factor influencing the reduction of the stability of the slopes. The increasing trend of annual rainfall has been a major challenge to meet the production requirement in Aruwakkalu limestone mine. The stability of the slopes in active quarry area of the mine under various rainfall intensities is studied in this paper. The slopes are modelled numerically by finite element method and subjected to analysis under strength reduction method semi coupled with transient seepage analysis. The results are expressed in terms of variations in factor of safety, pore water pressure and displacement with different rainfall intensities. Based on the results an economical bench design is recommended to be used when opening a new pit area.
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Background. Acid mine drainage (AMD) is a major environmental impact associated with the mining industry. Elevated acidic conditions resulting from the discharge of AMD into the surrounding environment can cause heavy metals to dissolve... more
Background. Acid mine drainage (AMD) is a major environmental impact associated with the mining industry. Elevated acidic conditions resulting from the discharge of AMD into the surrounding environment can cause heavy metals to dissolve and transport through water streams and accumulate in the aquatic environment, posing a risk to the health of living organisms. There have been several novel approaches in the remediation of AMD involving passive treatment techniques. The constructed treatment wetland approach is a passive remediation option that has proven to be a cost effective and long-lasting solution in abating toxic pollutant concentrations. Objectives. The present study investigates the applicability of water hyacinth (Eichhornia crassipes), a tropical aquatic plant with reported heavy metal hyper-accumulation in microcosm floating wetland treatment systems designed to remediate AMD with copper (Cu) and cadmium (Cd) concentrations exceeding threshold limits. Methods. Twelve wa...
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Non-destructive subsurface exploration methods could reveal subterranean characteristics with minimal consumption of time and resources. However, validity of such interpretations could vary depending on the appropriate use of the... more
Non-destructive subsurface exploration methods could reveal subterranean characteristics with minimal consumption of time and resources. However, validity of such interpretations could vary depending on the appropriate use of the controllable parameters in the geophysical method, with respect to the subsurface complexities. Accordingly, this study evaluates the sub subsurface characteristics of several locations revealed by the interpretation of resistivity data to understand the performance of different electrode configurations used in resistivity surveying. The electrode spacings maintained at each configuration was also critically assessed to identify the most appropriate for a particular instance of surveying. Furthermore, subsurface profiles were computed using three different interpretation methods to identify any influences from the interpretation method on the accuracy of the resultant profile. The results reveal a strong dependency of interpretations on the array configuration and maintained electrode spacing. And it was determined a suitable electrode spacing for improved subsurface interpretation. In order to improve accuracy of interpretations, it also suggests the need of developing an upper limit for current electrode spacing (AB) of the Schlumberger Array Configuration, given the general electrode spacing is maintaining a lower limit as AB > 5 (potential electrode spacing).
Smartphones have become an essential companion in most of the communities. Yet, we may not be quite aware of the capabilities and services that these devices could provide. As a result, features such as location services are underutilized... more
Smartphones have become an essential companion in most of the communities. Yet, we may not be quite aware of the capabilities and services that these devices could provide. As a result, features such as location services are underutilized and mostly used for navigation and location sharing. This study explores the limitations of embedded GPS receivers in smartphones with reference to the performance of a consumer-grade hand-held GPS device. The location coordinates obtained with the GPS unit and six smartphones on five locations over ten consecutive days revealed that over 70% of smartphone records provide the location coordinates within 0 to 10 m accuracy. Furthermore, at certain locations, over 75% of records have maintained the coordinate accuracy within 0 to 5 m. Hence, the use of smartphone location information in place of standalone GPS readings, can be recommended for moderate location accuracy requirements, such as geo-tagged data collection. Nevertheless, hand-held GPS units provide better approximations than the smartphones, for elevation readings at the studied locations. Accordingly, further investigations are recommended, to evaluate the discrepancies in elevation records, provided the ambiguities generated while recording the elevation measurements from the hand-held GPS units are minimized.
Beachrocks are sedimentary structures commonly observed where there is water in tropical and subtropical regions as a result of cementation by CaCO? of coastal sediments in the tidal zone. Comprehensive studies have been carried out to... more
Beachrocks are sedimentary structures commonly observed where there is water in tropical and subtropical regions as a result of cementation by CaCO? of coastal sediments in the tidal zone. Comprehensive studies have been carried out to determine the formation mechanisms of beachrocks specially Japan to improve an alternative countermeasure against erosion by man-made rocks. When focusing on formation mechanism of beachrocks elemental and mineralogical composition is vital. Considering this important application, we used spectroscopic techniques to understand composition of beachrocks in southern coastal region between Ahangama to Kaikawala and Uswetakeiyawa in the western coastal region of Sri Lanka. The presence of minerals in beach rock samples in southern coast were identified by FT-IR spectroscopic technique. The constituents of minerals present in the beach rocks are further confirmed by XRD technique. Elemental concentrations of beach rock samples have been analyzed using technique of WDXRF spectrometry. Uswetakeiyawa beachrock was mainly analyzed by using EDX in SEM. Beachrocks in southern coasts is comprise higher percentage of Aragonite which is the polymorph of CaCC>3, frequently founded in most of the sites in the world. Further the composition shown similarities with Indian (Tiruchendru) and Japan (Okinawa) beachrock occurrences. Comparative to the composition of southern coast beachrock, XRD analysis did not indicate any CaCO? polymorphs Uswetakeyvawa, beachrocks. Instead it indicated the presence of Kutnohorite (Ca(Mn,Mg,Fe)(CO?)2).
Water in the forms of rain, snowmelt and groundwater is identified to be the major factor influencing the reduction of the stability of the slopes. The increasing trend of annual rainfall has been a major challenge to meet the production... more
Water in the forms of rain, snowmelt and groundwater is identified to be the major factor influencing the reduction of the stability of the slopes. The increasing trend of annual rainfall has been a major challenge to meet the production requirement in Aruwakkalu limestone mine. The stability of the slopes in active quarry area of the mine under various rainfall intensities is studied in this paper. The slopes are modelled numerically by finite element method and subjected to analysis under strength reduction method semi coupled with transient seepage analysis. The results are expressed in terms of variations in factor of safety, pore water pressure and displacement with different rainfall intensities. Based on the results an economical bench design is recommended to be used when opening a new pit area.
is endowed with a rich base of industrial minerals despite its small land area. Traditional and modernized mining methods are employed to mine graphite, limestone, beach mineral sand (ilmenite, rutile, zircon and garnet), apatite,... more
is endowed with a rich base of industrial minerals despite its small land area. Traditional and modernized mining methods are employed to mine graphite, limestone, beach mineral sand (ilmenite, rutile, zircon and garnet), apatite, calcite, dolomite, quartz, feldspar, clay, kaolin, silica sand, mica and rock aggregate. Notably, some deposits have not been optimally exploited to their potential. Moreover, Sri Lanka does not have comprehensive information and documentation in the mining context. The mining method is selected on the basis of respective geology of the deposit, hardness of the ore and rock, depth, thickness and other geological aspects etc. The extraction of narrow steeply dipping vein deposits and deposits at great depth are significantly challenging and need specified selective mining techniques. In the study, currently practiced mining technologies, Cutand-Fill mining at Bogala, Open-stopping at Kahatagaha mines, open cast mining at Aruwakkalu Limestone quarry and mineral sand mining at Pulmoddai were investigated. The investigation was carried out through interviews and field visits. Site characteristics of each mine were tabulated, and the mining procedures were discussed. Mining methods employed at Kahatagaha and Pulmoddai were traditional while Bogala and Aruwakkalu utilize more systematic technologies. It is recommended to investigate and conduct indepth analysis in the second phase of the study for technological improvements.
Over 2500 quarry sites are currently in operation to cater the large requirement of rock aggregates in Sri Lanka. The concerns of this industry are not limited to the environmental and social aspects but significantly influence its own... more
Over 2500 quarry sites are currently in operation to cater the large requirement of rock aggregates in Sri Lanka. The concerns of this industry are not limited to the environmental and social aspects but significantly influence its own functionality. Even though such instances are common and under regular discussions, documented evidence and efforts to
methodically resolve them finds to be limited. Hence, only the adverse effects of the quarrying industry are mostly highlighted, sidelining the opportunities for sustainable development. This research attempts to systematically document the issues in the quarrying industry in Sri Lanka to address them based on three categories; Technical, Socio-environmental and Procedural. As an initial exercise the collected survey data was categorized on district basis, quarry grade, respondent’s skill level and the nature of the interviews conducted. Through cross analysis of these data clusters the most common concerns were extracted to prioritize according to the level of significance. Afterwards,
statistical significance of the relationships among the issues so far identified was computed mainly using Chi-squared-test and Binary Logistic Regression. Findings of this pilot study can be used for future policy development, even though they are dominantly represented
by the Colombo, Kalutara and Gampaha districts.
methodically resolve them finds to be limited. Hence, only the adverse effects of the quarrying industry are mostly highlighted, sidelining the opportunities for sustainable development. This research attempts to systematically document the issues in the quarrying industry in Sri Lanka to address them based on three categories; Technical, Socio-environmental and Procedural. As an initial exercise the collected survey data was categorized on district basis, quarry grade, respondent’s skill level and the nature of the interviews conducted. Through cross analysis of these data clusters the most common concerns were extracted to prioritize according to the level of significance. Afterwards,
statistical significance of the relationships among the issues so far identified was computed mainly using Chi-squared-test and Binary Logistic Regression. Findings of this pilot study can be used for future policy development, even though they are dominantly represented
by the Colombo, Kalutara and Gampaha districts.
in the classification process. The best performing algorithm in land cover classification was chosen for multitemporal analysis of the area of interest. In addition, false colour composites and spectral indices were generated using... more
in the classification process. The best performing algorithm in land cover classification was chosen for multitemporal analysis of the area of interest. In addition, false colour composites and spectral indices were generated using Sentinel 2 images to differentiate human-induced negative impacts and natural changes. The results show that Support Vector Machine outperformed other algorithms in classifying land cover near mining areas. Further, multitemporal analysis of land cover changes using this algorithm implies autonomous monitoring using satellite data was viable. Additionally, auxiliary information such as false colour composites and spectral indices confirmed that the increased proportion of water bodies in the area was due to leaving the abandoned mines without proper rehabilitation. This study provides evidence that the fusion of machine learning based classification with spectral indices helps develop robust monitoring systems.
The demand for minerals is rapidly increasing with industrialization, urbanization, and population growth. Sri Lanka has the potential to penetrate the world market with its endowed rich base of minerals despite its small land area.... more
The demand for minerals is rapidly increasing with industrialization, urbanization, and population growth. Sri Lanka has the potential to penetrate the world market with its endowed rich base of minerals despite its small land area. However, selecting a suitable mining method and its optimum utilization have significant roles in the growth of the local mineral mining industry. The lack of systematic approaches in mining methods is suboptimal for the economic growth of Sri Lanka, which demands immediate investigation and reassessment of contemporary mining practices. Thus, this study aims to critique the major mining practices and evaluate their suitability through characteristics and numerical analysis. This investigation was performed for underground mining methods: cut-and-fill stoping and open-stoping; surface mining methods: open-pit, and open-cast placer mining with reference to Bogala, Kahatagaha, Aruwakkalu, and Pulmoddai, respectively. A detailed study complying with the principles of the grounded theory was conducted through a multimethod approach followed by a thematic and content analysis along with the deductive approach. Moreover, the suitability of these methods was evaluated employing the University of British Columbia method through a numerical approach. This study reveals that the selections of mining methods are appropriate for all four mines, and mining practices are modernized and traditional, complying with site-specific requirements.
The mine environment is complex and highly dynamic due to the developments over time and surrounding climatic changes. Heedlessness to supply adequate quantity and quality of air will catalyse short and long-term ailments to the workers.... more
The mine environment is complex and highly dynamic due to the developments over time and surrounding climatic changes. Heedlessness to supply adequate quantity and quality of air will catalyse short and long-term ailments to the workers. Therefore, this study emerges as the new research frontier in incorporating software-assisted numerical simulation with analytical computations. This investigation assesses the existing ventilation parameters at the Bogala underground graphite mine for the propriety of the working environment. The uttermost bottom block between 240 and 275 fathoms (FM) levels was examined. The parameters were obtained through the in-field ventilation survey. Measured air quantity, psychometry, and air quality values were analysed and fed to the computer-simulated model. Moreover, the reentry time for a development drive at 275 FM level was estimated using the throwback method. Adequacy assessment unveils that all the parameters besides air quality are inadequate at most stations for optimal mine conditions to attain maximum efficiency. Furthermore, the re-entry time after the development blast at the selected drive is meager and necessitates re-calculation for each blast. Moreover, stale air mixing and air recirculation are extant at 240 FM and 275 FM levels, respectively. Thus, mine ventilation at Bogala needs to be optimised, admitting workers' health, safety and comfort, and productivity of the mine.
Durability is used to depict the obstruction of rock to weathering and the pace of events of such changes. Wetting and drying cycles cause evaluation of physical changes and slaking behaviour of rocks, and that can be appraised by the... more
Durability is used to depict the obstruction of rock to weathering and the pace of events of such changes. Wetting and drying cycles cause evaluation of physical changes and slaking behaviour of rocks, and that can be appraised by the slake durability test. Correlations between durability, mineralogy, and other physical-mechanical properties are different with the rock. Physical and mechanical characteristics of High-grade limestone samples and Lowgrade limestone samples from the Aruwakkalu mine were determined according to ASTM standard methods. X-ray diffractometer (XRD) analysis and scanning electron microscope (SEM) analysis were used to determine the mineralogical contents of the studied samples. Regression analyses were performed between the slake durability index and the physicalmechanical properties of limestones to identify the best wetting and drying cycle to assess the relationships. Differences between the physical, mechanical properties, and mineralogical contents of High-grade limestone and Low-grade limestone were also identified from the laboratory test results. Finally, this study will help to understand any rock engineering problem relating to durability, mineralogy, and other physical-mechanical properties of areas with limestone.
Generation of Acid Mine Drainage (AMD) is a problem that is associated with the urban mining of e-waste. Raised acidic conditions resulting from AMD discharge into the surrounding environments and cause toxic heavy metals (HMs) to... more
Generation of Acid Mine Drainage (AMD) is a problem that is associated with the urban mining of e-waste. Raised acidic conditions resulting from AMD discharge into the surrounding environments and cause toxic heavy metals (HMs) to dissolve, transport, and accumulate in the aquatic environments. Since the elevating concentrations of heavy metals due to AMD discharge exceed the threshold limits, beyond which the health of the living organisms is compromised, remediation of AMD has proven to be taken into consideration. Out of many strategies, passive treatment techniques can be mentioned as the newest approach to remediation AMD. Remediation methods for AMD can be divided into two categories, and they are active systems and passive systems. When comparing these two methods, active systems accrue more financial costs than passive treatments. More than 50 studies have focused on constructed wetland systems under passive technologies since it is self-sustaining once established, and they are cheaper than active treatment systems. The use of several aquatic plants such as water hyacinth, water lettuce, and water cabbage for the remediation process is of significance in constructed wetland systems. This study reviews the experimental findings on HM removal under several conditions using water hyacinth plants in different studies that have been done previously.
Lakvijaya coal power plant, which is in Norochcholai, Puttalam District, Sri Lanka, is the largest coal power plant in Sri Lanka. It annually produces about 150,000 tonnes of fly ash (FA) as waste, and the management of it is a pressing... more
Lakvijaya coal power plant, which is in Norochcholai, Puttalam District, Sri Lanka, is the largest coal power plant in Sri Lanka. It annually produces about 150,000 tonnes of fly ash (FA) as waste, and the management of it is a pressing concern. Various studies have been conducted to valorise FA in a useful manner without simply dumping it into the nearby lands. To this end, we propose the utilisation of FA in wastewater treatments to adsorb heavy metal ions in wastewater to promote environmental sustainability. The direct application of FA for that purpose may be questionable due to the contaminants present in the FA; however, it is reported commercially. Therefore, we attempt to initiate a preprocessed preparation route to ensure the leachate contains fewer contaminants compared to the use of raw FA. Washing is a commonly used preliminary pre-processing step, though it is not studied extensively in the literature with reference to the FA. Herein, we aimed to study the effects of the number of washing cycles and temperature on the characteristics of the FA. With the results, we could conclude that washing is an effective means of preprocessing to alleviate the contaminants of FA, en route for wastewater treatment.
Mining activities are influenced by stakeholders such as regulators, operators, service providers, customers, residents, and other interest groups. The governing bodies seem to fail to adopt a stakeholder inclusive approach to gain the... more
Mining activities are influenced by stakeholders such as regulators, operators, service providers, customers, residents, and other interest groups. The governing bodies seem to fail to adopt a stakeholder inclusive approach to gain the balance between the interest of the stakeholders and the organisational plans and revenues. Such issues are known at the surface level, but no solid quantitative approach has been used to scientifically prove their existence and associations. Thus, this study aims to find the issues with statistical evidence. Convenient sampling was used due to time restrictions and new work norms to pick a substantial number of respondents. A numerical assignment and logical ordering to qualitative data were done to perform the quantitative analysis. Factor analysis was used to find the principal components and the variables which mainly loaded the components showed significant interpretable correlations. The most significant factors associated with issues in quarry operations and management are found in terms of quality, reliability, and usage of monitoring, application of safety measures, quarry type based hazardous conditions, planning and maintaining quarry activities, combatting drilling issues via site planning, use of initiation technique by quarry type, the impact of environmental and social issues, handling public complaints and strategies to improve quarry operations.
Sri Lanka is rich in industrial minerals, including graphite, apatite, ilmenite, rutile, quartz, feldspar, kaolin, apatite, garnet sand, mica, calcite, and dolomite. Even though lots of mining methods are used to extract such minerals,... more
Sri Lanka is rich in industrial minerals, including graphite, apatite, ilmenite, rutile, quartz, feldspar, kaolin, apatite, garnet sand, mica, calcite, and dolomite. Even though lots of mining methods are used to extract such minerals, only limited studies have been carried out in Sri Lanka to evaluate mining methods by means of main mining principles, such as safety, economy, and efficiency. This study focuses on the Bogala graphite mine, a narrow vein medium depth underground mine, and Aruwakkalu limestone open pit mine. To evaluate the overhand cut and fill mining method in Bogala mine, Equivalent Linear Overbreak or Slough (ELOS), which is a useful measurement for quantifying the unplanned dilution in narrow vein mining, is used. The favourability of the underground mining method is evaluated for a particular mine site using Key Deposit Indicators (KDIs), and it provides the best suited underground mine based on characteristics of the ore body. The fracture system presence in the Bogala mine requires a good support system to ensure the safety of underground workers. The efficiency of the loading and hauling equipment in the Aruwakkalu mine site is evaluated by Match Factor (MF).
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The use of methodologies, practices, and activities are encouraged in engineering education to solve real-world problems for which knowledge generation and information transfer is vital. For this purpose, it is essential to have access to... more
The use of methodologies, practices, and activities are encouraged in
engineering education to solve real-world problems for which knowledge
generation and information transfer is vital. For this purpose, it is essential to
have access to authoritative information as much as possible. Dervin’s sensemaking
framework involves a process of seeking, encountering and using the
information to address an information need with respect to ambiguous and
complex real-world situations. Retrieving information on Bolgoda Ecosystem
for the purpose of environmental management was an activity with engineering
undergraduate library orientation during the pre-academic term. Accordingly,
the students have engaged in a guided literature search to retrieve information
from nine resources on a topic of interest from six categories of the Bolgoda
Ecosystem. This individual exercise comprising 13 hands-on sessions was
designed in line with the sense-making framework and created in MS Form.
The results were manually analyzed and evaluated for information retrieval
productivity with respect to relevance and document type. The results from
1169 search records revealed that 98.3% have selected a topic relevant to a
complex situation and they were able to retrieve 89.5% of appropriate document
categories that included 89.9% for books/reports, 90.3% for articles and 87.1%
for conference papers. It was also observed that Google Books, ScienceDirect
database and the Institutional Repository of Moratuwa University have been
mostly accessed for document retrieval. The productive use of sense-making
theory for information retrieval during a library orientation is evident from
this study. Also, it can be recommended as a tool to educate library users
on effective information systems and designing new information systems
engineering education to solve real-world problems for which knowledge
generation and information transfer is vital. For this purpose, it is essential to
have access to authoritative information as much as possible. Dervin’s sensemaking
framework involves a process of seeking, encountering and using the
information to address an information need with respect to ambiguous and
complex real-world situations. Retrieving information on Bolgoda Ecosystem
for the purpose of environmental management was an activity with engineering
undergraduate library orientation during the pre-academic term. Accordingly,
the students have engaged in a guided literature search to retrieve information
from nine resources on a topic of interest from six categories of the Bolgoda
Ecosystem. This individual exercise comprising 13 hands-on sessions was
designed in line with the sense-making framework and created in MS Form.
The results were manually analyzed and evaluated for information retrieval
productivity with respect to relevance and document type. The results from
1169 search records revealed that 98.3% have selected a topic relevant to a
complex situation and they were able to retrieve 89.5% of appropriate document
categories that included 89.9% for books/reports, 90.3% for articles and 87.1%
for conference papers. It was also observed that Google Books, ScienceDirect
database and the Institutional Repository of Moratuwa University have been
mostly accessed for document retrieval. The productive use of sense-making
theory for information retrieval during a library orientation is evident from
this study. Also, it can be recommended as a tool to educate library users
on effective information systems and designing new information systems
Research Interests:
Mining activities are influenced by stakeholders such as regulators, operators, service providers, customers, residents, and other interest groups. The governing bodies seem to fail to adopt a stakeholder inclusive approach to gain the... more
Mining activities are influenced by stakeholders such as regulators, operators, service providers, customers, residents, and other interest groups. The governing bodies seem to fail to adopt a stakeholder inclusive approach to gain the balance between the interest of the stakeholders and the organisational plans and revenues. Such issues are known at the surface level, but no solid quantitative approach has been used to scientifically prove their existence and associations. Thus, this study aims to find the issues with statistical evidence. Convenient sampling was used due to time restrictions and new work norms to pick a substantial number of respondents. A numerical assignment and logical ordering to qualitative data were done to perform the quantitative analysis. Factor analysis was used to find the principal components and the variables which mainly loaded the components showed significant interpretable correlations. The most significant factors associated with issues in quarry operations and management are found in terms of quality, reliability, and usage of monitoring, application of safety measures, quarry type based hazardous conditions, planning and maintaining quarry activities, combatting drilling issues via site planning, use of initiation technique by quarry type, the impact of environmental and social issues, handling public complaints and strategies to improve quarry operations.
The quarries which are abandoned ceasing operations without a proper closure plan cause negative impacts on the environment and also risk for the health and safety of society and the economy. This research focused on the environmental... more
The quarries which are abandoned ceasing operations without a proper closure plan cause negative impacts on the environment and also risk for the health and safety of society and the economy. This research focused on the environmental aspects that are affected by abandoned quarries and a sustainable methodology to design future land use. The objective of this research is to introduce a quarry rehabilitation method that is effective and has a positive impact on the environment, and applicable for abandoned quarries in Sri Lanka. In this respect, the district of Colombo has been chosen due to its importance in social and economic aspects. The research was conducted by identifying abandoned quarries through remote sensing and geographic information system technique (RS & GIS) analysis of satellite images of the concerned area. Prioritised two quarries among identified quarries for further analysis and suggested possible rehabilitation options. According to the land use analysis around the two quarries, the better rehabilitation option is to transform the lands into a vegetation area.
Surface water bodies in urban areas, such as Bolgoda lake, show complex vegetation dynamics, typically noticeable by the fluctuating vegetation cover throughout the year. Primary factors governing these fluctuations include wastewater... more
Surface water bodies in urban areas, such as Bolgoda lake, show complex vegetation dynamics, typically noticeable by the fluctuating vegetation cover throughout the year. Primary factors governing these fluctuations include wastewater discharge, anthropogenic activities (e.g., surface mining), invasive plant growth, and climate change. It is exceptionally challenging to physically measure and monitor these dynamics over the spatial extent of these waterbodies consistently over many years. Recent studies have explored the potentials of employing satellite imagery to quantitatively detect spatiotemporal changes of surface water vegetation cover. Such attempts have utilised vegetation detection indices, such as the normalised vegetation index (NDVI), to classify the vegetation cover with significant statistical accuracy. However, these conventional geospatial analyses require substantial computational power. They are limited to small timescales and spatial extents. This study employs the computational power of the google earth engine to address this limitation. Moreover, it integrates a machine learning classification approach, namely decision tree regression, to monitor the vegetation cover change over coarser and finer temporal resolutions using Landsat 8 hyperspectral imagery. Initially, NDVI classification was performed on 390 Landsat 8 images acquired throughout 2013-2021. Five locations, which represent different vegetation cover characteristics on the lake, were selected to generate the time series of the NDVI classified values. The results show that the vegetation cover varies at two temporal frequencies. The annual variation of the water, vegetation, and non-vegetation classes are undetectable. However, vegetation dynamics fluctuate rapidly at a finer temporal resolution (i.e., on monthly cycles). The statistically significant results claimed in this study will be further explored to support policymakers in optimising environmental resource management strategies and prioritising eco-preservation that can enhance the health and productivity of urban surface water bodies.
Beachrock is coastal sediment that has been cemented primarily by calcium carbonate within the intertidal zone in tropical and subtropical regions. Considering that beachrock has the potential to inhibit coastal erosion, we performed... more
Beachrock is coastal sediment that has been
cemented primarily by calcium carbonate within the intertidal
zone in tropical and subtropical regions. Considering that
beachrock has the potential to inhibit coastal erosion, we
performed laboratory tests to understand the formation
mechanism of beachrocks in southern coastal regions of Sri
Lanka. The mineralogical composition of beachrock samples
were identified by FT-IR spectroscopic technique. The
constituents of minerals present in the beachrocks were further
confirmed by XRD analysis. Elemental concentrations of
beachrock samples have been examined using WD-XRF
spectrometry. The formative environment (sea water) was
analyzed using EDTA titration, AAS, UV/Vis spectroscopy and
Iron Chromatography. The results reveal the presence of
minerals aragonite, calcite, orthoclase, quartz, albite, kaolinite
and lime in the beachrocks. According to the results, there is a
high probability to precipitate CaCO3 from the sea water in
southern coastal regions indicating a positive formative
environment for beachrocks. Hence, by appropriate regulation
of the conditions could foster the development of manmade
beachrocks to control the coastal erosion.
cemented primarily by calcium carbonate within the intertidal
zone in tropical and subtropical regions. Considering that
beachrock has the potential to inhibit coastal erosion, we
performed laboratory tests to understand the formation
mechanism of beachrocks in southern coastal regions of Sri
Lanka. The mineralogical composition of beachrock samples
were identified by FT-IR spectroscopic technique. The
constituents of minerals present in the beachrocks were further
confirmed by XRD analysis. Elemental concentrations of
beachrock samples have been examined using WD-XRF
spectrometry. The formative environment (sea water) was
analyzed using EDTA titration, AAS, UV/Vis spectroscopy and
Iron Chromatography. The results reveal the presence of
minerals aragonite, calcite, orthoclase, quartz, albite, kaolinite
and lime in the beachrocks. According to the results, there is a
high probability to precipitate CaCO3 from the sea water in
southern coastal regions indicating a positive formative
environment for beachrocks. Hence, by appropriate regulation
of the conditions could foster the development of manmade
beachrocks to control the coastal erosion.
In developing countries like Sri Lanka, waste management is a vital necessity. Solid waste dumps play a major role in handling waste in most countries. These solid waste dumps can cause severe environmental pollution via leachate... more
In developing countries like Sri Lanka, waste management is a vital necessity. Solid waste dumps play a major role in handling waste in most countries. These solid waste dumps can cause severe environmental pollution via leachate generation and transport of toxic material along with both surface and underground water flows. The Aruwakkalu waste dump, which is the subject of the study, is a sanitary landfill situated in Puttalam district, Sri Lanka. The landfill is planned to receive and store municipal solid waste (MSW) from Colombo metropolitan area. Locations for these waste dumps must be selected strategically to minimise the risk of contamination of the surrounding environment. A distributed hydrological model was used to determine the effect of rainfall, evapotranspiration, and surface runoff on the site. It identified the direction of the water flow through the waste dump. The analyses have illustrated that the area receives lesser rainfall and a higher rate of evapotranspiration. The hydrological analysis illustrates the water flow direction from the waste dump to the outside is towards the West and away from the nearby settlement areas. The results were used to assess the effect of the waste dumpsite on the surrounding water resources.
A comprehensive study for utilizing multispectral satellite imagery to enhance novel environmental monitoring techniques is crucial in terms of accuracy, processing time, and cost for a sustainable triple bottom. The accurate... more
A comprehensive study for utilizing multispectral satellite imagery to enhance novel environmental monitoring techniques is crucial in terms of accuracy, processing time, and cost for a sustainable triple bottom. The accurate classification of water bodies from other features optimizes spatiotemporal analysis to address global challenges. Therefore, this study emerges as the new research frontier in proposing an apt algorithm for recognizing water resources and coastline in Sri Lanka. This study explores the potential of using classification algorithms for geospatial assessments and applications with their accuracy and reliability. The acquired Collection 2 Level 2 Landsat 8 imagery was geometrically and radiometrically pre-processed, and a false-colour composite was produced from the bands: shortwave infrared, red and nearinfrared. A total of 280 training samples were created with the reference pixels of 50.13 percent for water bodies and 49.87 percent for other features. The confusion matrix was generated using a distinct set of 500 random points for each classification technique, and the F-score and kappa coefficient were calculated for the accuracy assessment. The study depicts that the supervised algorithms: Support Vector Machine, Maximum Likelihood and Random Trees, and unsupervised algorithm: ISO Cluster performs equally in classifying water bodies and other features with higher kappa coefficient exceeding 0.95. Out of these, ISO Cluster was efficient than other algorithms due to reduced handling time. The findings enhance the decision-making ability on extracting surface water bodies using freely available 30 m spatial resolution imagery.