Browsing by Author "Elakneswaran, Y"

Now showing 1 - 20 of 60

item: Conference-Full-text
Analysis of subsurface strata of Colombo and Gampaha districts of Sri Lanka, based on geotechnical investigation data
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Karunarathna, K.S.S.; Wasana, N.W.A.P.; Bandara, M.G.K.M.; Ranathunga, R.M.IG.N.K.; Samaradivakara, G.V.I.; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
The subsurface exploration for geotechnical engineering applications in Sri Lanka is mainly based on borehole investigations. Several leading geotechnical engineering companies in the country have already done more than a couple of thousands of subsurface investigations for small- and large-scale civil engineering projects. Even though project-wise subsurface information is available, integration of available subsurface data in proximity, and development of subsurface three-dimensional (3D) models can hardly be seen in the country. This has been a significant disadvantage in the cost and planning of large-scale new investigation projects. Due to lack of information, most of the projects start even without knowing the tentative bedrock level of the area. Hence, in investigation cost estimations, pricing for most of the items is recorded as “rate-only”, hence the total cost could immensely be higher than the available budget with the client. However, if 3D modelling of subsurface strata can be done area-wise, based on already available borehole data, such uncertainties could be minimized. In this research, more than a thousand subsurface investigation reports were reviewed; data were recorded and analysed targeting to interpret the subsurface of the western province of Sri Lanka, and to develop a 3D subsurface model for the same. However, scattered data had to be excluded in data analysis, and eventually, the study was confined to Colombo and Gampaha districts, in which more than sufficient data could be found. By using interpolation methods, surface strata were interpreted in between borehole locations by matching similar geological features. In addition, artificial neural networks were used to forecast borehole data in exceptional cases for a few locations. This helped to improve the spatial coverage and accuracy of the 3D model developed by means of “Surfer” software. The 3D model developed for the study area well demonstrates the subsurface strata and facilitates taking of cross sections in any direction within minutes. Hence, the findings of this research will enhance the outcome of general geotechnical investigation practice in Sri Lanka. This will also be immensely beneficial in planning and budgeting of future large-scale geotechnical investigation projects, more accurately than in the past, saving energy and time.
item: Conference-Full-text
Applicability of ground penetration radar (GPR) technique to optimize soil Nail Wall designs
Lasan, HLI; Weerasekara, MN; Prashanth, S; Abeysinghe, AMKB; Premasiri, HMR; Samaradivakara, GVI; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Soil nailing is used to stabilize existing natural slopes or excavations using soil reinforcement technique. Due to lack of information on ground profiles and thickness of soil layers, the required soil nail lengths cannot be determined in advance, for most of the steep slopes. Furthermore, the cost of drilling in fresh rock is much higher than the cost of drilling in soft soil and weathered rock. Without proper information on the depth at which the fresh rock is found, a cost-effective soil nail wall design cannot be finalized. This research was focused on studying the methods that can be used for soil nail wall design optimization by applying Ground Penetration Radar (GPR). The study was carried out on an unstable slope near Nursing Training School located in Kandy in the central part of Sri Lanka.The physical properties of soil were determined by direct shear tests, and stability analysis was done by means of “Slope-W” software. GPR techniques were also used in this study. The investigation results showed that the existing slope is unstable, and necessary to be protected. Further, it was identified that the basement rock cannot be encountered at already designed depths of the soil nails, which was subcequently proven as correctbased on data from ongoing drilling for soil nail installations. With the precise knowledge about the underground geological structure using GPR technique, the drilling cost, nail transporting cost, nail off cutting time to complete the total work can be reduced.
item: Conference-Full-text
Applicability of pre-heating techniques for recovery of garnet from garnet biotite gneiss
Jayakodi, JDSU; Weliwita, BY; Nishanthan, SS; Samaradivakara, GVI; Abeysinghe, AMKB; Rohitha, LPS; Vijitha, AVP; ; ; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
In mineral processing industry, the highest energy is consumed by crushing and grinding operations. However, if we can initiate micro cracks in the hard rock pieces in advance, we should be able to reduce the crushing energy and liberate useful minerals economically. Various pre-heating techniques have been tried by the scientists around the world to liberate minerals from rocks. In this investigation, pre-heating techniques were used to liberate Garnet from Garnet Biotite Gneiss. The market price of Garnet varies with the particle size. Hence, the samples were crushed and sized into industry needed three size fractions: (+250-850) μm, (+180-250) μm and (-180) μm. Afterwards, by means of Wilfley Table, Garnet was separated from rocks. Final Garnet recovery percentage was recorded for different temperatures. Furthermore, energy calculation was done for each sample to get an idea about the power consumption. It was observed that the crushing strength decreases with the temperature increment and it has been proven by identifying propagation of micro cracks in thin sections, prepared from rock samples pre-heat treated in Muffle Furnace and Microwave Oven. The analysis reveals that the preheat treated and quenched samples give higher Garnet recovery than Garnet recovered from as-received samples of Garnet rich Biotite Gneiss.
item: Conference Full-text
Application of emulsion explosive and comparative study on water-gel explosives for rock quarrying in Sri Lanka
Dharmaratne, PGR; Hemalal, PVA; Rohitha, LPS; Herath, B; ; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Dynamite has been the premier and the only high explosive used for mining and construction activities in Sri Lanka for a long period of time. Negative environmental impacts, effect on health and security hazards led to the Government of Sri Lanka (GOSL) to issue directives to find a suitable substitute for Dynamite. Subsequently, Water-Gel explosive was introduced in the year 2011. The poor performance of Water-Gels in wet conditions and it’s low Velocity of Detonation encouraged the use of Emulsion explosives. This research was focused on performing a comparative study of the performance of both Water-Gels and Emulsion explosives by analysis of the ground vibration and the blast air over pressures. The methodology adopted was to conduct ten blasts at one single metal quarry site keeping all other parameters constant. Blasting tests were performed using Emulsion explosives and Water-Gel explosives and the resulting ground vibration and Air-Blast overpressures were measured with Blastmate 111model for each blast. Calculation of mean fragmentation was done and particle size distribution based on photographic evidence of each blast was analyzed. Analysis was carried out demarcating the resultant production pile of aggregates covering a cleared zone. Grid lines inserted on the muck pile facilitated particle counting using photographs and calculating the mean fragmentation.
item: Conference-Full-text
Assessing the influence of microstructural features on deformation of rocks under triaxial loading
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Silva, SAV; Rathnapriya, RHDL; Riyasath, MSM; Dassanayake, ABN; Fujii., Y; Wickrama, MADMG; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
Assessing the influence of microstructural features on the deformation of rocks under triaxial loading is vital in rock engineering applications, aiding safe and efficient operations by predicting the deformation of rocks. Triaxial testing offers the simulation of stress conditions within a rock to examine the deformation of rocks with confinements. This research focuses on how microstructural features, such as cementing material and pore geometry, affect the deformation behaviour of rocks subjected to triaxial loading. Two rock types were considered in this study: Kimachi sandstone (medium hard clastic rock) and Bibai sandstone (hard clastic rock). The progressive failure behaviour under Hydro Mechanical (HM) coupling effect was analysed by stress-strain distribution and the fracture geometry was examined using CT images of the specimens which were tested under different confinements. Thin sections were analysed to examine the changes in porosity and the effect on the cementing material with the confinement. The results of the proposed approach reveal a clear influence of the effective confinement on the failure of rocks and how it influences the porosity and cementing material of rocks. It is found that the Bibai sandstone shows a brittle failure and a shearing deformation while Kimachi sandstone shows a brittle to ductile failure and shearing to compaction deformation with the confinement due to the less presence of cementing material within Bibai sandstone compared to Kimachi sandstone. Therefore, with the confinement, the porosity of Bibai sandstone increases while it decreases in Kimachi sandstone. The results highlight the differences in the failure mechanism of a particular rock type for the same effective confinement which is a result of only a partial contribution of the pore pressure on the failure. These findings provide valuable insight into the assessment of microstructural features on the deformation of rocks under triaxial loading, aiding in the development of safer and more efficient rock engineering operations.
item: Conference Full-text
Assessment of seasonal impacts on groundwater quantity and quality in upstream of Malwathu Oya Basin
Madhushankha, JML; Madhuwan, ARB; Menan, P; Chaminda, SP; Abeysinghe, AMKB; Jayawardena, CL; ; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Malwathu Oya Basin which covers 2350km2 located in Anuradhapura district is considerably populated and the safety and the available quantity of water is crucial for the people. Water samples were collected from selected locations during South- West monsoon period, Second Inter monsoon period and North-East monsoon period from September 2016 to March 2017. The samples were analysed for pH, turbidity, conductivity, fluoride, chloride, magnesium and calcium as basic drinking water quality parameters. Only the shallow regolith aquifers are considered for the study. The groundwater quality variation of the area shows a considerable variation from dry season to rainy season in general water quality of the area, and is in acceptable limit for most of the basic parameters. With the seasonal changes Fluoride and Chloride content is higher than permissible limits in some areas.
item: Conference Full-text
Bioremediation of lead-contaminated mine waste using microbially Induced carbonate precipitation
Mwandira, W; Nakashima, K; Kawasaki, S; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
The aim of this study was to use microbially induced calcium carbonate precipitation (MICP) technique to bioremediate lead using bacterium Pararhodobacter sp. Laboratory scale experiments conducted, achieved complete removal of lead. This result was further confirmed by SEM and XRD analysis that indicated coprecipitation of calcium carbonate (CaCO3) and cerussite (PbCO3). Furthermore, syringe test demonstrated that MICP based sequestration of heavy metals via coprecipitation with calcium carbonate may be useful for lead bioremediation. Very few low-cost in situ heavy metal treatment processes for lead bioremediation are available; therefore, bioimmobilization of lead by MICP has the potential for application as a low-cost and eco-friendly method for heavy metal remediation.
item: Conference Full-text
Characteristics studies on engineering properties of river sand substitutes for conventional concrete and mortar works
Withanage, AK; Sugathadasa, AGMRP; Mithushan, T; Dissanayake, D; Rohitha, LPS; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
The main sand source of construction industry in Sri Lanka is river sand. However, being a developing country, the demand for river sand increases gradually. Based on engineering computations, sand demand for 2013 was estimated to be 12,266,186m3. The GSMB currently keeps records of all the licenses issued for sand mining and transportation, and according to these records the approximate annual sand supply is 7,132,631m3(GSMB records), which is far below the estimated demand. The difference may compensate by to illegal mining. Thus, this kind of unrestricted harvesting of sand is resulting in heavy rates of soil erosion; land degradation; increased river-water turbidity; lowered water tables; salinity intrusion in the lower reaches of rivers. Further, over use of river sand for construction industry has various undesirable social and ecological consequences. As a solution for this, various alternatives such as offshore sand, quarry dust, manufactured sand, dune sand, washed soil, waste building material, broken glass and blast furnace slag have been identified by various countries. Thus, this study attempts to identify suitable alternatives for river sand to mitigate the environmental issues related to river sand mining in Sri Lanka. In this project, we use manufacture sand, quarry dust, beach sand and off shore sand to test the suitability for conventional concrete and mortar works. Basically testing for concrete strength using uniaxial compressive strength and check grading of all river sand substitutes are performed. In addition to that two types of sand were mixed in various ratios and check those concrete and mortars for the compressive strength test to find the best mix ratio of sand for construction purposes. Finally those results were compared with strength of concrete for which river sand was used.
item: Conference-Full-text
Characterization of heavy minerals in Nilaveli and Batticaloa beach stretches
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Benjamin, R; Anojithan, M.; Lokugamhewa, S.W.; Ratnayake, N.P.; Abeysinghe, A.M.K.B.; Premasiri, H.M.R.; Dushyantha, N.P.; Batapola, N.M.; Dilshara, R.M.P.; Iresha, H.; Elakneswaran, Y; Dassanayake, A.; Jayawardena, C.
The northeastern coast of Sri Lanka is notable for its significant heavy mineral deposits, especially the Pulmoddai deposit (containing 70-85 wt% heavy minerals) and the Verugal deposit (containing 45-50 wt% heavy minerals). However, regions like Batticaloa and Nilaveli remain underexplored and show potential. This study conducted a comparative analysis of these two beaches stretches to characterize their heavy mineral content in beach sand. Twenty-four composite samples were collected along the Batticaloa (n=17) and Nilaveli (n=7) stretches. Bromoform separation was used to determine their heavy mineral contents, followed by petrographic microscopic grain counting to ascertain the volumetric percentage of each heavy mineral type. The results revealed a higher mineral content in the Batticaloa beach stretch (1.20-14.50 wt%) compared to Nilaveli (0.36-6.42 wt%), despite Nilaveli's proximity to the Mahaweli River. The Batticaloa beach stretch showed average contents of 53.14% ilmenite, 2.06% rutile, 6.44% garnet, 31.94% zircon, and 4% monazite, indicating a significant potential for economically valuable monazite. The high heavy mineral content identified in the Batticaloa beach stretch suggests that further detailed explorations are warranted to assess the economic viability of the deposit.
item: Conference-Abstract
Comparison of critical metal potential in beach and offshore sediments of Pulmoddai, Sri Lanka
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Nanayakkara, C.J.; Ratnayake, N.P.; Premasiri, H.M.R.; Abeysinghe, A.M.K.B.; Ratnayake, A.S.; Dushyantha, N.P.; Batapola, N.M.; Dilshara, R.M.P.; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
The global transition towards renewable energy resources for power generation has increased the demand for critical metals (CMs), including rare earth elements (REEs). This rapid growth of demand coupled with geological scarcity and geo-political concerns has posed great challenges in securing the supply chain of CMs. Therefore, prospecting new CM sources worldwide is of timely importance. In this context, the Pulmoddai coastal stretch in Sri Lanka has been recognized as a dynamic deposit with established potential for REEs and other critical metal resources, currently undergoing beach face mining operations. The focus of this study is to compare the critical metal potential in the beach and offshore sediments in Pulmoddai, Sri Lanka, crucial for determining the origin and delineating the extent of this deposit. Twelve onshore and nineteen offshore samples were collected and analyzed for CMs (V, Cr, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, and Cs) and REEs. Based on the results, light REE content (LREE), heavy REE content (HREE), and total REE content (TREE) were computed for both onshore and offshore locations. For onshore sites, LREE, HREE, and TREE ranged respectively from 43.27 to 244.09 ppm, 19.62 to 92.29 ppm, and 62.92 to 336.39 ppm. Conversely, offshore locations exhibited higher concentrations with the corresponding values ranging from 116.12 to 363.62 ppm, 8.57 to 120.93 ppm, and 167.93 to 484.55 ppm. Sr, Ni, and Cr were determined as the most abundant CMs for both onshore and offshore locations. Sr, Ni, and Cr concentrations ranged from 227.17 to 674.58 ppm, 116.17 to 675.88 ppm, and 43.55 to 112.87 ppm respectively for the onshore locations. The corresponding ranges for offshore sites were determined as 370.86-754.30 ppm, 235.43-721.44 ppm, and 32.51-172.62 ppm. The higher CM content in offshore regions suggests an offshore origin to this dynamic deposit, which is enriched by the offshore sediments transported onshore and deposited on a long-term basis. Therefore, regulatory authorities overseeing the mining operations of Pulmoddai deposit should accurately delineate its extent, integrating both onshore and offshore regions as a unified system, rather than solely focusing on prospecting the longshore areas.
item: Conference Full-text
Critical evaluation of current environmental comfort conditions of Bogala underground
Lasantha, MML; Thushath, T; Somarathne, KGMS; Hemalal, PVA; Dharmaratne, PGR; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Ventilation is a basic part of all underground mine operations as fresh, cool air is required to remove stale, affected air from the workings. The inadequate ventilation often is the cause of lower worker efficiency leading to decreased productivity and increased accident rates. This study focuses on the evaluation of environmental comfort conditions in Bogala Underground, a medium-depth underground graphite mine located in Aruggammana, Sri Lanka. A detailed ventilation survey was carried out taking measurements of dry bulb temperatures, wet bulb temperatures, Dry Kata and Wet Kata thermometer values, air velocities, surface air temperature and barometric pressures at strategic points covering the entire mine. All results were compared with corresponding standard values which describe the standard conditions to be met for working underground. Recommendations were made to improve the present environmental comfort conditions by installing auxiliary fans in stopes where necessary which will enhance the immediate mine environment contributing to health and safety aspects of the underground working environment.
item: Conference Full-text
Demand estimating model to forecast the building material requirements for the construction and allied industries in Sri Lanka
Maduranga, WWDD; Nithushan, N; Jayasinghe, JKSN; Dissanayake, DMDOK; ; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Over the past few years, there has been a high level of interest in modelling demand estimation for the construction and allied industries in Sri Lanka. Demand estimation is a process that involves coming up with an estimate of the level of demand for a product or service and, typically confined to a particular period of time, a month, quarter or year. Demand estimation methods can be categorized into two main categories according to the technique applied to analyse data. Different approaches are survey methods and statistical methods. For a good quantitative analysis, statistical methods are more preferable. Regression analysis method which comes under econometric statistical method is more preferable to develop demand estimation models since it has high accuracy level. In the regression analysis, there are two methods to develop the model. These are Single Regression Analysis and Multiple Regression Analysis. The few steps to develop the estimation models are statement of a theory or hypothesis, model specification, data collection, estimation of parameters, checking goodness of it, hypothesis testing and forecasting. In this project, there are two models for sand and ABC materials each and the first model is for dust and ¾ particle size. Developed model for chip particles was rejected due to inaccuracy of the unavailability of required data. In validation, sand and ¾ particle size have shown very high accuracy when as dust and ABC has shown quite lower accuracy.
item: Conference Full-text
Development of a methodology to map railway lines and surrounding land use using UAVs
Manatunga, UI; Munasinghe, N; Premasiri, HMR; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
High accurate railway maps and terrain information (Digital Elevation Models) is a major concern for future railway constructions and railway lines development.The mapping of railway line using ground based surveying techniques istime consuming and problematic.Unmanned Aerial Vehicles (UAV) technology has revolutionized the aerial photogrammetric mapping due to its low cost and high spatial resolution. It enables mapping the land use with greater accuracy in both 2D and 3D. The “DJI Phantom 4“ drone was selected as the UAV platform to acquire image data. In this study, we have developed a fully automated and highly accurate engineering approach for detecting land use and railway line, which is based on textural information from orthophoto and elevation information (Digital Surface Models)obtained from the drone.The Pix4D software was used to develop the orthophoto and a Digital Surface Model (DSM) and the DSM was validated by using the ground control points.The rule sets knowledge-based classification method in object oriented classification was used to classify the land use and railway with the use of “eCognition“ software. Finally, the results were compared with digitize land use layer to validate the results, and obtained overall accuracy of 90.15%.
item: Conference-Abstract
Development of a numerical simulation method for complex fracture process of rocks based on 3-D ECZM-FDEM using GPGPU parallel computation
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Takarada, K; Fukuda, D; Di, W; Liu, H; Ogata, S; Maeda, Y; Min, G; Kawasaki, S; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
For the developments of surface and underground mines, numerical simulation has been regarded as a highly crucial approach in terms of mining design and safety. The combined finite-discrete element method (FDEM)[1] has attracted significant attention for reasonably simulating very complex fracture processes of rocks. FDEM is based on the continuum mechanics model considering finite-strain theory, the cohesive zone model (CZM)[2] by utilizing initially zero-thickness cohesive elements (CEs) and potential-based contact mechanics model. The FDEM based on the intrinsic CZM (ICZM), which inserts the CEs at the onset of the simulation, has been the mainstream of previous studies applying FDEM due to its simpler implementation. Although the FDEM is generally known as a computationally expensive numerical method for both two-dimensional (2D) and three-dimensional (3D) problems, the computational acceleration of the ICZM-based FDEM can be achieved with relative ease through parallel computation using general-purpose graphics processing units (GPGPUs). However, the accuracy of continuous deformation when rock is intact is significantly compromised in the ICZM. The FDEM based on the extrinsic CZM (ECZM), which activates CEs only when and where the local stress reaches the given activation criteria, is expected to overcome this issue. However, although the implementation of 2-D ECZM-based FDEM with the GPGPU parallel computation has been reported, its 3-D counterpart has not been achieved. Based on this background, this study proposes a novel master-slave algorithm to achieve the implementation of the GPGPU-parallelized 3-D ECZM-based FDEM. Figure 1 shows the examples results of GPGPU-parallelized 3-D ECZM-based FDEM for uniaxial compression test simulation and spalling test simulation [3]. These results indicate that the developed ECZM-FDEM can reasonably reproduce the fracture and failure patterns of rocks in both static and dynamic tests compared to laboratory tests. The significant advantage of the proposed approach lies in the fact that the precision of continuous deformation can compared to those of the parallelized ICZM-based FDEM. The proposed approach could be an important basis for the further developments of the ECZM-based 3-D FDEM for simulating very complex 3-D rock fracturing processes in the various rock engineering problems.
item: Conference Full-text
Diamond core drilling for narrow vein graphite exploration - as practiced at Bogala Mines, Sri Lanka (A Case Study)
Ekanayake, EMKB; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
The vein type graphite deposits which are rich in carbon found in Sri Lanka occur in metamorphic rocks as narrow steeply dipping veins. In Sri Lanka, generally these graphite deposits are explored by diamond core drilling technique. This technique has revolutionized the mining industry and directly resulted in the discovery of many minable ore bodies that would otherwise have gone untapped. Generally in this technique, possible ore bodies (veins) are explored by drilling a series of exploratory drill holes according to a pattern of drill holes designed by a competent geologist. After receiving core samples and related data sheets, core logging activity is carried out by the geologist for each and every bore hole. It is usually one of the last stages of exploration, and with data taken from core logging can be used to interpret 3-dimentional view with the support of software like Surpac. Finally it would be possible to determine whether the prospect is economically viable or not for mining. This paper looks at the suitability of diamond core drilling technique practiced in exploring narrow graphite veins in Bogala Graphite Mines of Sri Lanka and will discuss in detail pros and cons of the applying method.
item: Conference-Abstract
Disaster and attitudinal vulnerability: a systematic conceptual review
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Senavirathna, C; Rajapaksha, S; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
Natural hazards represent a destructive force that poses a significant risk to human life, property, and the economy, among other aspects. The impact of natural hazards on the economy and human populations is profound. Various attitudes, beliefs, and behaviors are linked to different demographic groups, some of which may be more susceptible to these hazards than others. In developing nations, catastrophic natural events like tsunamis can deliver a sudden blow to their development trajectory, leading to a costly and challenging recovery process. A key contemporary challenge in disaster preparedness involves the effective application of soft measures, focusing on assessing local awareness, knowledge, perception, and attitudes towards disasters. The primary research inquiry in this investigation pertains to understanding the existing knowledge surrounding attitudinal vulnerability to disasters. The aims of this study include conducting an extensive review of current knowledge on attitudinal vulnerability in disasters and identifying potential avenues for future research.PRISMA framework and guidelines have been followed to conduct this systematic conceptual review. Total of 128 articles were initially identified from the Scopus database using the key words “Disaster”, “Vulnerability” and “attitude”. Review protocol has been developed according to the PRISMA guidelines. Analysis method used in this study was keyword co-occurrence utilizing the VOSviewer software (Version 1.6.20). The principal discoveries of this theoretical manuscript encompass the delineation of forthcoming avenues for research and areas of research deficiency, such as knowledge lacunae, empirical deficiencies, contextual deficiencies, and methodological deficiencies. A comprehensive framework is imperative to grasp the extent of the matter, encompassing both the technical and social repercussions. Subsequent research endeavours should concentrate on the amalgamation of Blockchain and the internet of things to facilitate real-time data utilization in the realm of disaster readiness. Initiatives aimed at enhancing disaster preparedness should specifically target younger demographics for enhancement purposes. In conclusion, the influence of past experiences on current and future preparedness needs to be explored enhancing public attitudes and knowledge of climate change and disaster risk
item: Conference-Full-text
Distillery spent wash as an alternative fuel in boilers and potash recovery from that ash remaining in boilers
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Warnakulasooriya, G.A.P.K.G.G.; Amarasinghe, A.M.P.C.; Lankathilake, L.J.M.U.; Wijesekara, E.R.J.M.D.D.P.; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
Waste management stands as a critical global environmental challenge, with a growing emphasis on waste avoidance and the generation of revenue through byproduct recovery. Pollution prevention strategies aim to minimize waste generation, while waste minimization efforts focus on reducing waste volume or toxicity, often through water recycling, process modification, and byproduct recovery. In this context, the utilization of distillery effluent in agriculture presents an opportunity to save on fertilizer costs, enhance agricultural output, and mitigate pollution. However, molasses-based distilleries, along with their primary product, alcohol, generate significant volumes of wastewater known as spent wash. Improper disposal of spent wash into water bodies or land leads to a host of environmental issues. Consequently, recent efforts have shifted towards waste minimization and revenue generation through byproduct recovery. This study focuses an approach to address the challenge of distillery spent wash management by drying the spent wash and utilizing the resulting dried solids as an alternative fuel for boilers. The distillery spent wash contains approximately 14.6% solid content, and the dried solids have a gross calorific value of 13840 J/g. Furthermore, the dried solids possess an ash content of 2.26%, with the ash containing a notable 36.7% potassium oxide content. By transforming distillery spent wash into a valuable resource for boiler fuel, this research not only addresses waste management concerns but also offers a sustainable solution for revenue generation. The utilization of dried solids as an alternative fuel for boilers contributes to reducing environmental pollution associated with improper spent wash disposal while offering a viable source of renewable energy. This study underscores the potential of waste-to-energy initiatives in fostering sustainable waste management practices and enhancing economic viability in the distillery sector.
item: Conference Full-text
Dynamics of the Madu-Ganga Estuary
De Silva, UHNH; Somasiri, RBHP; Jayasekara, NNL; Ratnayake, AS; Dushyantha, N; Weththasinghe, SM; Samaradivakara, GVI; Vijitha, AVP; Ratnayake, NP; Abeysinghe, AMKB; Dassanayake ABN; Elakneswaran, Y;
Among the estuaries in Sri Lanka, Madu-Ganga Estuary plays a significant role to generate a massive income through tourism. The existing tropical ecosystem attracts the tourists. However, this ecosystem faces problems of environmental deterioration problems which affect the tourism industry and income of the local community. Therefore, this research is mainly focused for understanding hydro dynamics and sediment dynamics process in Madu-Ganga Estuary. The four field visits were carried out to cover southwest and northeast monsoon periods. In situ and laboratory tests were conducted for surface and bottom water samples of Madu-Ganga Estuary to analyse the quality of the water. In addition, grab and core samples and sub-bottom profile data were used to identify sediment distribution patterns of the estuary. Moreover, time series satellite images were used to identify nearshore sediment dynamics along the western coast of Sri Lanka. Results show that a significant variation of water quality parameters under the estuary mouth opened and closed conditions. The spatial variation of chloride content also indicates that estuary mouth opened condition plays a major role to control seawater invasion in this aquatic system. Sub-bottom profile data shows cyclic/seasonal changes in accumulation of sediments in Madu-Ganga Estuary. Time series satellite images indicate that sand can probably receive from the southern region by predominant longshore currents during the southwest monsoon. Further studies are recommended to identify lake ecosystem responses to physicochemical changes and to design seasonal mining capability.
item: Conference-Full-text
Effect of fracture stiffness in a fault damage zone on seismic source parameters of induced fault-slip
(Division of Sustainable Resources Engineering, Hokkaido University, Japan, 2024) Gang, M; Sainoki, A; Kodama, J; Iresha, H; Elakneswaran, Y; Dassanayake, A; Jayawardena, C
It is well recognized that inherent stress concentration within a fault damage zone may lead to induced fault-slip, resulting in severe damage to underground facilities. Previous research suggests that the intensity of fault-slip is influenced not only by the mechanical properties of the fault core but also by the stiffness of the surrounding rock mass, implying that fracture stiffness could be an important factor that needs to be studied. Therefore, in this study, the effect of the fracture stiffness on seismic source parameters of induced fault-slip is investigated using a mine-wide scale heterogeneous continuum model. The model is constructed based on a discrete fracture network within a fault damage zone, utilizing the crack tensor theory and boundary traction method. The fault core is simulated as a discontinuous plane with interface elements at the center of the model, and fault-slip is induced by gradually reducing the effective normal stress on the fault plane. Seismic source parameters are computed and analyzed under various fracture stiffness conditions. Seismically radiated energy is defined as the work done by the stress perturbation across a closed surface at a distance from the earthquake source, while seismic moment is calculated using the moment tensor of a seismic source in an anisotropic medium. This study investigates increasing fracture stiffness while maintaining a normal-to-shear stiffness ratio of three. Dynamic analysis results reveal a notable impact of fracture stiffness on seismically radiated energy and seismic moment, both of which decrease significantly with increasing fracture stiffness. These findings imply the importance of considering fracture stiffness for more accurate estimation of seismically radiated energy and seismic moment.
item: Conference Full-text
Effect of organic bio-polymer on bio-mineralization of CaCO3
Nawarathna, THK; Nakashima, K; Kawasaki, S; Abeysinghe, AMKB; Dassanayake, ABN; Elakneswaran, Y
Organic matrix in the biogenic CaCO3 has a significant influence on the CaCO3 crystal growth, its polymorphs and morphology. In this research, effect of the cationic and anionic organic bio-polymers on the crystallization of CaCO3 was investigated in microbial induced carbonate precipitation (MICP) process. In the current study, poly-L-lysine and poly-glutamate were used as cationic and anionic biopolymers, respectively. Urea hydrolysis by ureolytic bacteria Pararhodobacter sp. led to CaCO3 formation in the presence of Ca2+ ions. The reaction was conducted with the addition of the polymers under different conditions. After oven-drying precipitation, the amount of precipitate was measured and morphology of the precipitate was analyzed by using scanning electron microscope. Bell-shaped curve was obtained in the relationship between the amount of the precipitate and the poly-L-lysine concentration. However, amount of precipitate remained approximately constant with the increase of the poly-glutamate concentration. In the presence of poly-L-lysine, morphology of the crystals changed from well-developed rhombohedral crystals to ellipsoidal shaped aggregates. But in poly-glutamate addition, polyhedral and spherical crystals are predominant.