SLIIT International Conference On Engineering and Technology Vol. 02 [SICET] 2023
Permanent URI for this collectionhttps://rda.sliit.lk/handle/123456789/3551
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Publication Open Access Microplastic Content in Non-Point Source And Point Sources of Colombo And Suburbs – Experimental Study on the Impact of Seasonal Variation(Sri Lanka Institute of Information Technology, 2023-03-25) Ariyawansha, R.B.V.K.; Gomes, P.I.A.Microplastics, which can enter aquatic environments through various sources, are small plastic pieces that are less than 5 mm in length. There are two types: primary and secondary microplastics. Sri Lanka has limited studies on microplastics in inland water bodies, so this research aims to quantify the levels of microplastic pollution in Colombo's surface waters in a spatiotemporal manner. Samples were taken from Beira Lake, Dutch canal network, Talangama canal, in wet and dry seasons. Microplastic concentrations were determined using NOAA guidelines and an optical microscope. Statistical analysis was performed using IBM SPSS version 21, including One-way Anova and Pearson correlations to identify significant differences and correlations. The study found that Dutch Canal had the highest average microplastic concentration of 12.7 mg/L during the wet season, and the lowest of 4.2 mg/L during the dry season. Both Dutch Canal and Talangama canal showed significantly higher microplastic concentrations during the wet season than the dry season, while the opposite was found in Beira Lake. The statistical analysis showed significant differences between microplastic concentrations in wet and dry seasons in all three water bodies. The microplastic levels in Beira Lake were higher on the surface water during the dry season (4.32 mg/L) and wet season (13.77 mg/L) compared to point sources (4.05 mg/L and 11.68 mg/L, respectively). Furthermore, Dutch canal's point sources showed higher during the dry season (8.47 mg/L) than the wet season (11.51 mg/L) and concentration of microplastics on the surface water was higher during the wet season (5.73 mg/L) than the dry season (7.16 mg/L). Talangama canal had similar patterns to Beira Lake. The study found microplastic contamination in urban and semi-urban surface waters at levels comparable to some industrialized countries, highlighting a concerning issue.Publication Open Access Health, safety, and environmental impacts of road infrastructure projects in Sri Lanka; Impact analysis on ongoing and temporarily suspended road works(Sri Lanka Institute of Information Technology, 2023-03-25) Kariyawasam, D.D.S.A.; Gomes, P.I.A.Road networks are considered to be the primary mode of transport in Sri Lanka. Road infrastructure plays an important role in the country’s economy. The work environment of construction projects is generally considered one of the most dangerous places for work. The current economic recession faced by Sri Lanka has led to the temporary suspension of road works. The aim of this study is to identify the main types of health, safety, and environmental issues that occur in the construction of different ongoing and suspended road infrastructure projects in Sri Lanka. Questionnaire surveys, discussions, and site observations were carried out to collect data from road projects of different classes. Data analysis was done using the SPSS (Version 28) statistical software. The findings of the research indicated that vehicle collisions were the most common type of occupational accident faced in road construction in Sri Lanka. The fatality rate caused due to poor health and safety management of road construction works was compared with the construction of buildings and other developing countries. The results obtained from the study also identified that negligence was the main factor that influenced low safety standards on-site, which in turn impacted the performance of the construction project. Measures taken by construction companies of different grades to improve health and safety standards were also studied in the research. It was also evident that suspended road projects had an adverse effect on the environment, as it was seen that these sites possessed a loss in diversity, high chances of sediment erosion, and a rise in mosquito breeding locations. The findings of this research highlight the need of prioritizing health and safety in road projects and also enable construction companies to handle construction work in a way that minimizes environmental damage occurs.Publication Open Access Determination of the Growth Curve of Chlorella sp. under Optimum Conditions in Automated Growth Chambers for Biofuel Production(Sri Lanka Institute of Information Technology, 2023-03-25) Viduranga, S.A.V.; Balasooriya, B.L.W.K.; Bandara, N.G.C.Microalgae have a great potential for producing biofuels because of their capacity to accumulate high content of lipids. Chlorella sp. is the mostly applied microalgae sp. for biofuel production at the industrial level. The current study aimed to determine the optimum conditions for mass culture Chlorella sp. and to generate a growth curve to determine growth patterns over time. The samples were collected from Chlorella pure cultures available in the laboratory. Chlorella colonies were identified morphologically. Liquid cultures were prepared in BG 11 medium, The effects of four different temperatures (20°C, 25°C, 30°C, and 35°C), two light intensities (6000 lux and 2000 lux.) under aerated and non-aerated conditions on the growth of Chlorella cultures in 250 mL flasks (n=3) were studied using a custom-designed automated growth chamber using Arduino technology. The culture growth was monitored by determining the cell density (cells/ml) and light absorbance (750 nm) at 0, 96, 192, 288, and 384 hours after inoculation. and After 16 days, cells were harvested (6000 rpm, 5 min, room temperature) and the dry biomass (g/ml) was measured after oven drying at 70 °C. Optimal conditions for the efficient mass culture of Chlorella sp. were found as 30 °C temperature, 6000 lux light intensity with aeration conditions. Under those optimum growth conditions, 6L photo-bioreactors were designed. Absorbance and cell density (cells/ml) of Chlorella sp. were monitored with time to develop the growth curve of Chlorella sp. The growth of isolated Chlorella sp. was characterized by an exponential phase from 8.86 to 45.41 hr after inoculation with a specific growth rate of 0.06 hr-1 and a doubling time of 11.46 hr. The Chlorella growth rate was 0.027 hr-1 without optimum conditions, and the doubling time (Tg) was 25.6 hr.Publication Open Access OPTIMUM ROUTE PLAN FOR EFFECTIVE COLLECTION OF AN INDUSTRY LEVEL BY PRODUCT/WASTE(Sri Lanka Institute of Information Technology, 2023-03-25) Peiris, M; Gamlath, I; Bandara, SEffective waste management is critical for sustainable development in manufacturing industries, especially in managing industrial waste. Industrial waste can be transformed into high-quality products through circular economic practices, promoting sustainable development. This research aims to develop a methodology to identify an optimal route plan for collecting and distributing industrial waste and products, promoting circular economy practices. To achieve this objective, waste generated by a selected industry needs to be investigated to determine its potential for reuse in other industries. Data on the quantity and variety of waste generated daily was collected, and industries that use waste as a resource to develop their products were identified. The linkage between industries that demand waste as a raw material and those that generate waste can be established using a Geographical Information System. The study focuses on concrete demolition waste and aims to link metal crushing, aggregate suppliers, and concrete block manufacturing industries. The optimized route plan would benefit third-party subdistributors, reducing transportation costs and facilitating effective transportation. Additionally, it would enable new entrepreneurs to establish industries and maintain a good supply chain, creating jobs.Publication Open Access Development of Roughness Prediction Model for Sri Lankan Expressways(Sri Lanka Institute of Information Technology, 2023-03-25) Nilawfer, S; Madushani, S; Sandamal, K; Gomes, AExpressways play a pivotal role in industrial and export development in Sri Lanka by providing access to the production sector in addition to the passenger transport in between transport hubs. A reliable pavement performance prediction model is essential for pavement management systems to optimize the cost of maintenance and rehabilitation planning. In this study, pavement roughness prediction of expressways in the long-term performance was conducted using International Roughness Index (IRI) which is used as a global parameter to measure the ride comfort of road users and the unevenness of pavement. Firstly, initial IRI values for Sri Lankan expressways were established by using current data and found that, it varies between 0.90 to 1.45 m/km. Secondly, IRI prediction model developed with cumulative traffic volume, considering outer lane IRI as the dependent variable due to higher deterioration rate compared to inner lane. Moreover, it was found that, there is a good relationship between IRI with cumulative traffic with R-squared of 0.60. Further, it can be concluded that, the outcomes of this study can be effectively used for Sri Lankan context in long term performance evaluation and expressway maintenance planning.Publication Open Access Effect on Time Management Due to Variations in Road Construction Projects in Sri Lanka(Sri Lanka Institute of Information Technology, 2023-03-25) Atapattu, A.L.S.O.; Bandara, R.P.H.S.Variations are reoccurring and inevitable incidents in construction projects. It alludes to any adjustment in project scope at any instance of construction process. There are numerous causes of variation depending upon different parties involved, complexity of project and the type of project. These variations are acknowledged to affect different viewpoints of the projects. The thesis evaluated the effect of time management due to variations in road projects in Sri Lanka to diminish them. In order to achieve the study objectives, a basic survey of literature review was done accompanied with a quantitative survey with industry experts were carried out to gather data on impact of time management due to variations in construction projects. Through the writing study, 50 causes of variation orders were recognized but, they were shortlisted since there were so many similar causes. Out of them design faults were identified as the major cause of variations. When it comes to the impact on time overrun, it was discovered that variations affect on time of a project adversely. Finally, mitigation strategies for variations have been proposed in the study. The recognized results from literature overview were moreover subjected to a test by the 33 specialists in the industry including contractors, consultants, and clients to be more precise. The results were analyzed using SPSS. The study's final recommendation is that to all parties to get involved, to reduce variation orders beginning with the initial design phase, manage variation orders during the construction phase using an efficient change management system, and adopt various technologies to speed up the variation management procedure.Publication Open Access Computational Approach for Determining the Variation of Coefficient of Secondary Compression in Secondary Settlement Prediction of Soft Soils(Sri Lanka Institute of Information Technology, 2023-03-25) Thilakarathne, T.M.D.; Vidurapriya, K.V.D.; Thilakasiri, H.S.Secondary consolidation settlement takes place in soils after the completion of primary consolidation settlement, which is due to the dissipation of pore water pressure under the applied loads. The secondary settlement usually occurs due to the plastic adjustment of the soil particles and most commonly takes place in organic fine grained soils or soft soils. Hence, it is important to accurately estimate the secondary settlement in soft soils as the final stability of infrastructures built on soft soil grounds mainly depends on the amount of secondary settlement that takes place after the end of primary consolidation settlement. The coefficient of secondary compression (C) is a governing parameter in predicting the secondary settlement which is the slope of the consolidation curve for void ratio versus time. Also, various empirical correlations have been found by the past researches to find the value of the coefficient of secondary compression. In most of the instances, the secondary settlement is estimated by considering the coefficient of secondary compression as a constant value. However, the C value shows a variation with time and this could affect the secondary settlement estimation. Hence, it is necessary to investigate how the variation of coefficient of secondary compression affects the estimation of the secondary settlement in soft soils. In this study, the settlement data obtained from the Weligama Bay Marriot Resort and Spa project, Sri Lanka, is compared with the settlement values obtained from a computer generated programme. The progarmme simulates the settlement by considering the variation of the coefficient of secondary compression and by considering a constant coefficient of secondary compression value. The results show that the consideration of varying coefficient of secondary compression (with time) gives more accurate results than considering a constant coefficient of secondary compression in settlement prediction in soft soils.Publication Open Access Using Coconut Fibre To Improve The Tensile Characteristics Of Concrete(Sri Lanka Institute of Information Technology, 2023-03-25) Jayamanne, B.C.D.; Velauthapillai, SEven though the building industry is modernizing in terms of technology and materials used, construction costs have risen, as has the environmental impact. The behavior of coconut fiber in a concrete structure is described in this paper. Coconut fiber increases a range of technical qualities in concrete. Sustainability is a generally accepted concept in today's construction industry. Coconut fibers have the highest tenacity of any natural fiber. They can be used for reinforcement in low-cost, basic concrete structures. The experiment will be conducted out on concrete with fibre inclusion in four different mix proportions (0%, 2%, 4%, and 6% by weight of the cement). This experiment will assess the compressive strength and split tensile strength of coconut fiber-reinforced concrete after 7 and 28 days. This test is sufficient for M20 and M30 grade concrete. According to this study, CFRC with a fiber fraction of 2% had the best Split Tensile Strength. Additionally, adding coconut fibers reduces the compressive strength of concrete.Publication Open Access Strength Gain of Organic Soil Deposits Subjected to Increase in the Effective Stress(Sri Lanka Institute of Information Technology, 2023-03-25) Nanayakkara, D.A.S.; Thilakarathne, T.M.D.; Thilakasiri, H.S.Organic soil has weak shear strength properties in its natural texture. However, a significant gain in strength can be achieved in such soils by increasing the effective stresses using preloading techniques. This research focuses on the organic soil deposits in Sri Lanka by analyzing the data from Colombo- Katunayake Expressway (CKE) project and Elevated Highway (EH) project spanning from New Kelani Bridge to Athurugiriya. As a developing country, Sri Lanka is facing a huge challenge due to its limited land available towards the infrastructure development. Therefore, construction should also be directed on organic soils despite of considering its weak shear strength properties as the soil can be modified to enhance its properties. To predict the strength gain of organic soils subjected to effective stresses, empirical correlations are used such as Skempton and Bjerrum equation (1957). As depicted in such correlations, the ratio of undrained shear strength and effective overburden pressure is observed against the Plasticity Index (PI) using field data. From the results of the analysis, it is discovered that using empirical correlations is very conservative for organic soils within the Sri Lankan context. Particularly, use of empirical correlations is very safe but beyond the economic considerations. In the extension of the research, an argument is generated to validate the use of PI to predict normalized shear ratio. To validate the argument, SPSS statistical software was used to perform the multiple regression analysis having PI, natural void ratio and organic content as the independent variables. From the statistical analysis, it was found that using only PI to predict the strength gain is not conservative for Sri Lankan organic soils subjected to effective stresses. These generated results are identical to conclusions drawn governing the inorganic soils in the state of Missouri (2011).Publication Open Access Development of Coir Fiber Reinforced Polymer Reinforcing Bars for Concrete Structures(Sri Lanka Institute of Information Technology, 2023-03-25) Tharmarajah, G; Wimalasuriya, W.B.UAt present, global warming increment and petroleum reserve depletion have been a major threat to the environment. These occur due to various human activities. Construction industry contributes 40 % for the global carbon emission. From that 10% is contributed from the manufacture of cement and the rest is contributed by the other requirements in the construction industry. Therefore, scientists are now more focused to involve bio-based products to minimize the emission of carbon. This resulted in, paying more attention towards the natural composite materials that can be used instead of artificial materials. Scientists are eager to find natural materials which are locally available. The structures built today, does not survive the entire service life of the structure. This is due to corrosion of steel, especially in coastal areas. So, in order to overcome this, use of a natural material which can provide the same tensile strength can be used. Over the past few decades engineering materials like composites, plastics, ceramics has dominated the engineering industry. There are new polymer materials introduced such as glass fiber, carbon fiber and aramid but they are not eco-friendly. The main problem associated with these is the high production cost. Therefore, new composites which are environmentally friendly should be found in order to replace other materials. Even though there has been much research published on different natural fiber composite materials, here an attempt has been made to use coir to produce reinforcement bars in order to combat corrosion