Institutional-Repository, University of Moratuwa
Welcome to the University of Moratuwa Digital Repository, which houses postgraduate theses and dissertations, research articles presented at conferences by faculties and departments, university-published journal articles and research publications authored by academic staff. This online repository stores, preserves and distributes the University's scholarly work. This service allows University members to share their research with a larger audience.
 Research Publications |  Thesis & Dissertation |  E- Books |
 UoM Journal Publications |  UoM Conference Proceedings |  Articles published in Scimago's Q1 journals |  UoM Research Reports |  Other Articles authored by UoM staff |
Recent Submissions
item: Thesis-Full-text
Improvement of urban environment through sewer network monitoring using CCTV technology
(2022) Senarath, SPND; Perera, A
The Colombo Municipality has recognized that the maintenance of the sewer network is an important part of upgrading the city’s urban environment. However, The Maintenance of the Colombo Municipality Sewer Network is a challenging task due rapid deterioration of the pipe system. The city sewerage system which is 100 years old has frequently experienced collapses and overflows, operation failures due to Sulphide attacks, root ingress, and infiltration to the pipe. More ever, Prior identification of the Failure location and carrying out proactive maintenance work is vital and becomes extremely difficult due to limited budgetary provisions and the lack of actionable information on the underground sewer network. Apart from that, CMC does not possess advanced asset management software to predict the pipe renewal plan. So, it was a challenge to make immediate decisions on the underground utility service's rehabilitation and quickly attend to repair work.
This Thesis has presented a study for developing an asset Management framework that accurately assesses the condition of pipe segment, the status of sewer pipe, and lastly, identifies the most sustainable rehabilitation priorities of sewer network within the particular catchment. The catchment area has 40 km of sewer network has been assessed in this study, ranked according to the maximum grade of sewer lines, and identified potential risks within the sewer system. And scientifically derive pipe renewal schedules based on economic, social, and environmental aspects. The study of the pipe segments area has identified that the pipe distress is localized and randomly distributed, not depending on the age of the asset. It has been found that most of the pipe segments in the network need replacement within the next 10 years. In comparison, 63% of pipe segments require immediate action on rehabilitation within five years to prevent the failure of the pipe.18% of pipe segments require to be attended to within 5-10 years.14% of pipes require to be repaired within 10-20 years. Sound management of the underground pipe infrastructure can be achieved by paying more attention to environmental aspects than economic aspects. Every outcome of the study may be used by the municipality and other agencies handling underground pipe networks. Every outcome of the study may be used to sustain the city sewer network. It will be beneficial not only for delivering the service but also for improving the environment of the city.
item: Thesis-Full-text
Production of polyhydroxyalkanote (PHA) biopolymer from waste products of fruit-based food industry, Sri Lanka
(2022) Jayalath, BSU; De Alwis, A; Kothalawala , KWPM
Recently, conventional petrochemical-based plastic waste has been a global crisis, creating numerous environmental and economic challenges. Addressing this problem, the present study was aimed to assess the feasibility of bacterial polyhydroxyalkanoates (PHA) synthesis from locally available lignocellulosic fruit waste obtained from the fruit-based industry in Sri Lanka. The present study was focused on assessing the feasibility of bacterial PHA synthesis from locally available lignocellulosic fruit waste obtained from the fruit-based industry in Sri Lanka. This study investigated the viable of using papaya (Carica papaya), mango (Mangifera indica), watermelon (Citrullus lanatus), and pineapple (Ananas comosus) fruit wastes as substrates for PHA production. The pure strain of Bacillus subtilis bacterium was selected as the microorganism for 72 h fermentation process to produce PHAs under ambient temperature conditions. The bacterial strain cultured in modified LB agar media was stained with Sudan Black B (SBB) as a preliminary screen to confirm PHA production. Two pretreatments (Crude aqueous extract: CAE, and sulphuric acid treatment: SAT) were performed to analyze total reducing sugars in fruit waste. Comparatively the highest concentration of reducing sugar was obtained with SAT pretreatment method. Maximum average value of cellular dry weight (CDW) was obtained in papaya waste (2.15 ± 0.15) g/L at 60 h of fermentation and minimum value was obtained in watermelon (1.23 ± 0.06) g/L after 72 h of Fermentation. Fourier transform infrared spectra (FTIR) were performed for the obtained extracted samples, and PHA synthesis was confirmed by the corresponding peaks of PHA functional groups. The proof-of-concept stage was realized to promote PHA to be developed from fruit wastes.
item: Thesis-Full-text
Performance evaluation of constructed wetland for tertiary treatment
(2022) Punchihewa, NPDG; Jayaweera, MW
The textile industry in Sri Lanka is a leading apparel manufacturer worldwide, with a state-of-the-art dye house and a well-equipped automated laboratory with physical and washing test facilities. The dye plants inside the factory deploy high-tech methods such as exhaust dyeing (hank and high pressure) and piece dyeing (continuous dying) for polyester, nylon, and cotton fabrics. A chemical wastewater treatment plant (1,000 m3/day) has been installed to treat the factory's wastewater (process wastewater and domestic wastewater). The quality of the treated effluent meets the tolerance limits for industrial wastewater discharge into inland surface waters, reducing environmental harm. As requested by the Central Environmental Authority (CEA), a constructed wetland and fishpond have been incorporated into the existing wastewater treatment facility to improve the treated wastewater quality and ensure that no harmful chemicals remain in the treated wastewater discharged into a nearby waterway. The wetland is a sub-surface flow type where no water column is maintained, and the wetland area is around 1acre. Phragmites spp. (Phragmites karka) has been planted. The medium in which plants are grown comprises broken burnt clay disposed of from tile factories. A 50% void ratio was maintained for the easy flowing of wastewater through the wetland. The zigzag configuration is maintained throughout the wetland to avoid the short- circuiting phenomenon. The research study showed removal efficiencies of 72.3%, 51.8%, 47.2% 25%, and 73% for the contaminants COD, BOD, TSS, TKS, and TP, respectively. The temperature and pH almost remain the same with little variations. data showed faecal coliform levels were less than 2 MPN/100 ml throughout the data collection period. The study suggests that, if appropriately operated, constructed wetlands might have been effectively utilized for tertiary wastewater treatment under local circumstances. As a result, constructed wetlands can be included in the treatment process to modify existing underperforming wastewater treatment plants as well as a sustainable green concept.
item: Thesis-Abstract
Development of a biologically active moss wall system as a sustainable exterior building envelope
(2026) Nelundeniya, SW; Baskaran, K
The integration of sustainable systems into the built environment is a critical response to the growing impacts of climate change, particularly in tropical regions. This research investigates the development and evaluation of a biologically active moss wall system as a sustainable exterior building envelope, with specific emphasis on structural feasibility, thermal performance, cost and environmental sustainability within the context of Sri Lanka’s tropical climate. A prototype moss wall system was designed using lightweight steel framing, moisture- retentive substrate layers, recirculating irrigation system and moss species adapted to local climatic conditions. Structural performance was analysed via analytical modelling and manual calculations to determine load-bearing capacity, wind resistance, and overall stability. Thermal performance was assessed through experimental monitoring by constructing four models using brick masonry, cement block masonry, plywood model with moss and double-layer configuration with moss. In addition, a computer simulation using DEROB-LTH, and as the results deviated from the actual measurements, a parametric study was carried out varying the factors relevant to solar radiation, thermal conductivity, specific heat, density, solar absorptance, and thermal emittance. Cost analysis was conducted for both conceptual and detailed designs, while sustainability evaluation was benchmarked against Sri Lanka Green Building Council (SLGBC, 2017) criteria. The actual measurement results indicated that moss-integrated walls particularly double-layer configurations, maintained lower indoor temperatures and higher relative humidity than masonry and cement block walls, indicating enhanced microclimatic stability and passive regulation of temperature and humidity. Although discrepancies were observed between measured results and DEROB-LTH simulations, parametric sensitivity analysis confirmed consistently improved thermal performance for moss walls. Structurally, the system meets design standards and allows flexibility in configuration, while the passive irrigation system maintains adequate moss hydration with minimal water consumption. Environmental benefits include improved air quality and potential mitigation of urban heat island effects. This study concludes that biologically active moss wall systems constitute a structurally viable, thermally efficient, and environmentally sustainable building envelope solution for tropical climates. The integration of such systems offers potential for reducing energy demand, enhancing occupant comfort, and contributing to urban sustainability. Further research is recommended to explore full-scale applications, design optimization, comprehensive lifecycle assessment and integration with smart building technologies.
item: Thesis-Abstract
Evaluate the relationship pf parking volume with land use, urban density, capacity of the roads and accessibility in the Kurunegala MC area
(2026) Wedagedara, WGRK; De Silva, C
Countries like Sri Lanka is having a well urbanized were having huge traffic congestion even at the off-peak time. As per the City of Kurunegala Development Plan Prepared for 2021-2030, road density in Kurunegala city is similar to the road density of other developed countries. Since the public transportation system in the city is weak, many people tend to use their vehicles for daily traveling purposes and it causes high traffic in the peak time.
As knowledge was investigated, build-up form has a direct impact on the making of trips and mobility. However, most of the literature also found that making a new trip depends on factors of travel behavior such as travel demand and travel supply. However, there is a lack of empirical evidence using parking-based indicators in medium-sized Sri Lankan cities. According to the theory of accessibility, a trip is not normally an end in itself but more of a means to make another trip for the activity. Hence, it is clear that travel behavior in a particular area represents the real relationship between urban factors. The study examines the level of accessibility in the selected research study area by analyzing parking volume as a proxy indicator of vehicle-based spatial attraction, rather than as a direct measure of trip generation. Parking volume represents the concentration of vehicle arrivals attracted to a location due to its accessibility characteristics. To assess this relationship, key urban form factors namely capacity of road, land-use mix, and urban density are quantified for the selected sample locations. The analysis focuses on identifying how variations in this accessibility related urban parameters are associated with differences in measured parking volumes within the specific urban area. Based on the regression analysis, the accessibility index is the main factor that affects the parking volume and other measured indices like Capacity of Road index, Density index, and land use mix index have lower significance when compared to Accessibility. However, those independent factors and dependent factor were also related by 59.8% in regression model. Hence, the accessibility is the one of major factors to be considered in the urban planning and transport planning as a tool for their decision-making process as well as molding process.