SLIIT International Conference On Engineering and Technology Vol. 01 [SICET] 2022

Permanent URI for this collectionhttps://rda.sliit.lk/handle/123456789/2988

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Open Access
Aeroacoustic Noise Produced from Novel Wind Turbine Rotor Design for Small-scale Applications in Sri Lanka
(SLIIT, 2022-02-11) Perera, M; Bandara, U. H
Growing concerns regarding non-renewable energy sources have driven academic and industrial scholars as well as global superpowers to seek sustainable, greener power generation alternatives. One such prominent renewable substitute is wind power which was initially utilized in harnessing electricity towards the late nineteenth century though archaeological evidence has proved that wind power had been employed for various purposes since predynastic Egypt. Extensive research and development has enabled the efficient operation of multi megawatt wind farms at present though inherent drawbacks still persist, of which aerodynamic noise, also referred to as aeroacoustic noise, is of major concern. This paper details the simulative investigation of the aeroacoustic sound levels produced by an optimized novel wind turbine design intended for the use in small scale applications with medium wind speed conditions in Sri Lanka, using ANSYS Fluent. A transient analysis using the Shear Stress Transport turbulence model was used to obtain the converged pressure fluctuations which subsequently revealed the sound pressure levels via Fast Fourier Transforms at six predetermined locations of interest. The results revealed the presence of acoustic vibrations within the Infrasonic and Low Frequency Noise range with sound pressure levels exceeding one hundred decibels, particularly up to a frequency of twenty five Hertz. Prolonged exposure to elevated levels of low frequency noise has been identified to cause severe discomfort to humans though further conclusive research is required. Finer mesh controls which incorporate minute boundary layer variations during motion and precisely encapsulate the turbine geometry could further improve the accuracy of the results, however this would require adequate computational capacity. The results of this research primarily serve as a basis for identifying possible improvements for the novel rotor design in addition to providing a comparative study for future research, both simulative and empirical, on the aerodynamic noise emissions associated with wind turbines.
Open Access
Affordable and Reliable Video Laryngoscope with Wireless Connectivity
(SLIIT, 2022-02-11) Dassanayake, I; Senanayake, K; Katakumbura, I; Senaviratne, L
Along with the pandemic situation across the world, the resilience of using ordinary medical devices is limited. Also the demand for medical devices which are used to diagnose COVID-related diseases rapidly increased. Taking all these facts into consideration, a new laryngoscope device was developed with exciting functionalities. The proposed device is affordable and comes with remote monitoring capabilities. An ordinary video laryngoscope uses an expensive camera module to capture video streams, and the proposed device uses ordinary USB camera modules which are cheap and affordable. Therefore, it is even possible to replace/discard camera modules each time after investigating COVID-related patients. The proposed USB camera and Laryngoscopic blades can be easily replaced for a very affordable cost. In the proposed system, a real-time video stream can be remotely monitored in multiple displays, including personal mobile devices. Since the live video footage can be streamed across the world, expertise in the field can monitor and consult promptly. This device broadcasts video wirelessly through LAN (local area) and WAN (wide area) networks in real-time. So far, the device transmits live video streams wirelessly with less than 250ms latency on LAN networks, and 500ms to 1000ms latency in WAN networks. An inbuilt rechargeable power supply will power up the device for ~ 45min in continuous use.
Open Access
Aspects of Structural Vulnerability against Tsunamis
(SLIIT, Faculty of Engineering, 2022-02-11) Dias, P
Using historical data, it is shown that tsunamis may not occur for earthquake magnitudes even up to Mw = 8. Field data can be used to arrive at generalized fragility curves for different materials of construction as functions of inundation depth. Such curves can also be integrated into vulnerability curves that can be characterized by simple negative exponential equations. It is also possible to create synthetic fragility curves generated by Monte Carlo simulation, which were found to have a reasonable fit with the empirical ones. While most simulations focus only on the structural frames in buildings, partitions can also play a significant role in damage mechanisms. There is also a role for simplified indices of either risk or robustness, based ideally on physics rather than expert opinion. Such indices can also be used to consider risk to an entire system, for example buildings, functions and backup services that are spread across adjacent coastline hospitals.
Open Access
Assessment of Nationally Determined Contributions of Sri Lankan Power Sector
(SLIIT, 2022-02-11) Dahanayake, A; Fernando, G; Liyanage, M
The nationally determined contributions (NDCs) aim to attend long-term temperature goals, which have been imposed by the Paris agreement to strengthen climate change efforts. Fossil fuel is the major energy source in power generation in Sri Lanka, contributing 67% of total input energies. Sri Lanka is intended to achieve 70% renewable energy in the power sector by 2030 and achieve carbon neutrality in the power sector by 2050 through its NDCs. This study analysed the NDCs in the Sri Lankan power sector. The study was carried out through Asia-Pacific Integrated Assessment Model (AIM/End-use), a recursive dynamic least-cost optimisation framework based on bottom-up modelling principles. The Sri Lankan Power sector has been categorised into a few sectors based on the fuels used in power generation. It mainly considers thermal coal, thermal oil, and hydro. It will also consider all the existing power generation technologies, committed technologies and technologies identified as candidates. A business-as-usual scenario (BAU) and three alternatives NDC were considered in this study. These NDCs include enhancing renewable energy by adding 3867 MW, converting existing fuel oil-based combined cycle power plants to natural gas and establishing new natural gas plants, and improving the efficiency of transmission and distribution network (lost reduction 0.5% compared with BAU by 2030). The study analysed the output data and confirmed the feasibility of meeting GHG emission reduction targets through consideration of selected NDCs in the time span of 2020-2030. The GHG emissions from the BAU scenario and three countermeasure scenarios were analysed in 2015-2050. The input primary energy supply was determined to compare the variation in energy with the effect of NDCs
Open Access
Causes for Death and Injuries in Construction Industry in Sri Lanka
(SLIIT, 2022-02-11) Wijesekara, M; Fernando, P; Gunarathna, N
The construction industry plays a vital role in the socio-economic development in any country. However, it has been recognized as one of the most hazardous industries in many counties around the world because of the nature of activities and tasks performed at construction sites. Similarly, presentday construction industry of Sri Lanka prioritizes and considers safety as a primary, complex issue due to its high impact on the industry. Accordingly, the aim of this study was to identify the causes for deaths and injuries in construction sites in Sri Lanka and identify actions to mitigate those accidents. The data collection was in the form of documentary review, semi-structured interviews, and questionnaire survey. This study found that the nine (9) most prominent types of accidents that have occurred in Sri Lankan construction sites include falling from heights and scaffoldings, falling debris or objects and machinery accidents. During the last 10-year period 2,135 accidents have been recorded in the construction industry, including both fatal and non-fatal accidents, among which 311 were fatal accidents. As per the study findings, during the period of 2010 – 2020, 14 fatal construction accidents were reported out of every 100 construction accidents. Usually, most of the accidents at construction sites are due to lack of safety at site, working without PPE, inadequate training and lack of supervision. Further, the study also recommends strategies to minimize the identified nine (9) most prominent types of accidents and to improve construction site safety. Findings of this research could help towards reducing the fatal and non-fatal construction accidents in Sri Lanka and to develop safe work environment in the local construction industry.
Open Access
Challenging Arbitral Awards in the Construction Industry
(SLIIT, 2022-02-11) Jayasinghe, R; Dahanayake, R; Edirisinghe, V
One of the most common alternative dispute resolution methods used in the Sri Lankan construction industry is arbitration. However, challenging arbitration awards based on legal grounds at the courts has been a current trend by the disagreeing party. If this situation occurs continuously, the purpose of having arbitration as an alternative dispute resolution method can be abandoned. Therefore, the study aims to identify the causes where arbitration is challenged in multi-story building construction projects in Sri Lanka through a case study. The methodological choice was qualitative and used semistructured interviews from six arbitrators and 2 case studies that referred to courts to challenge arbitration awards as research strategies. The study found the poor attitude of parties, lack of technical knowledge, reliability, and capability of the arbitrator to act according to the arbitrary acts imposed by the government as the main causes. Further. The study recommends arbitrators consider the reasons to act well enough and reject the cases if the arbitration is likely to be challenged in courts, train arbitrators to be reliable and on technical knowledge, and improve parties' attitudes by educating on the arbitration procedure and its benefits.
Open Access
Conflicts Handling Styles Used by Professionals at Pre-Contract Stage of Building Construction Projects in Sri Lanka
(SLIIT, 2022-02-11) De Silva, p; Sandanayake, Y. G
Conflicts between design team professionals is a common experience in building construction projects in Sri Lanka. Depending on the way they are been handled, these conflicts bring either positive or negative impacts to the project. Thus, this paper investigates the conflict-handling styles that the professionals use to handle different types of conflicts among themselves at pre-contract stage of construction projects in Sri Lanka. The study on different types of conflicts and handling styles were derived through quantitative approach by a questionnaire survey designed incorporating Rahim’s Organisational Conflict InventoryII (ROCI-II) with the participation of 42 number of professionals engaged during the pre-contract stage of building construction projects in Sri Lanka. The scope of the study was limited to the building construction projects and only to the conflicts among professionals at the same level. The collected data were analysed using descriptive statistics. The research findings revealed that there are four types of conflicts: task, relationship, process and status conflicts, occur in different frequencies among the professionals. The task conflicts occur very often, and process conflicts occur often whilst relationship and status conflicts occur rarely among professionals during the pre-contract stage. This study revealed that professionals use different conflict handling styles to handle these four types of conflicts among themselves during the pre-contract stage of building construction projects in Sri Lanka. Further, majority of professionals use integrating style often to handle conflicts among themselves, and they use avoiding style very rarely to handle the conflicts among themselves except for relationship conflicts. However, to handle relationship conflicts, professionals use dominating style as the last option. The study would assist the industry practitioners to identify their personnel conflict handling style and the outcome of using each style with their supervisors when handling conflicts during the precontract stage.
Open Access
Construction Project Risk Management for Performance Improvement (Polgahawela-Pothuhera-Alawwa Integrated Water Supplying Project)
(SLIIT, 2022-02-11) JAYASINGHE, S. M. I. A.; WEERAKKODY, F
Construction risk management can be defined as the avoidance or the reduction of possible harmful incidents or actions in a construction project. It can be one of the most important factors in a construction project. Depending on the nature of the project, types of risks can be very wide in its range. Understanding the risk factors and the proper management of them, can lead a project to be completed on schedule, avoiding budget overruns whilst ensuring the safety and welfare of all the project participants. This research aims to identify the risks and their possible impacts on a specific construction project. The selected project is the construction of the Polgahawela-Pothuhera-Alawwa Integrated Water Supplying scheme located in the North-Western province of Sri Lanka. Risks categorized under the different sectors such as financial management, technical, quality, health, and safety, environment, social, legal and political were considered in the research but limited to the construction phase of the project. The methodology for this study is based on ISO 31000, which includes risk identification, risk analysis, risk evaluation and risk mitigation. To identify the relevant risks of the project, a structured interview using a questionnaire was conducted among selected project participants. In making the assessments founded on the responses received, weighted credits were assigned based on the academic and professional qualifications of the respondents. The responses were utilized in this manner to develop a listing of risk and its consequences. This highlighted the more severe risks enabling recommendations to be made to mitigate and manage such risks. The risk management process together with knowledge from previous literature was used in making recommendations to mitigate and manage risk towards project performance improvement. It should be noted that the findings could be of benefit to future contractors associated with similar projects.
Open Access
Converter Control for Integration of Renewable Energy into the Grid
(SLIIT, Faculty of Engineering, 2022-02-11) Annakkage, U
Generation of electricity using renewable sources of energy will be the only option available to us soon. This may happen within the next two decades. In the meantime, we make the transition form traditional synchronous generator driven power systems to fully renewable energy-based power systems where the energy source is integrated through power electronics converters. We must start thinking in a new way. This presentation will address the technological challenges associated with connecting renewables to the grid through converters and the options available to meet those challenges. While the ability of the converters to respond fast is an obvious advantage, unlike the synchronous generator, it does not have a rotating mass that stores kinetic energy. The short-term overcurrent rating of the converter is much less than that of a synchronous generator unless the converter is overdesigned. Addressing these engineering challenges will be discussed in the presentation.
Open Access
CRITERIA FOR SELECTION OF SUITABLE SITES FOR RAINWATER HARVESTING IN THE MIDDLE EAST FOR AGRICULTURE USE: A REVIEW STUDY
(SLIIT, 2022-02-11) Zubaidi, S; Harris, C; Carnacina, I; Abdellatif, M; AL-Hasani, B
In arid and semi-arid regions, rainwater harvesting represents an important alternate source of water supply around the globe. The middle east is an integrally dry zone and due to climate change, it has experienced a severe drought for the last decade that made the situation worse. Many countries are suffering from awful water crises due to increasing water demand for agriculture and rapid urbanization. Therefore, unconventional water supply resources practices such as using rainwater harvesting for agricultural purposes can be possibly used to tackle water scarcity. Numerous researchers have established different criteria and methods to identify suitable sites selection techniques for rainwater harvesting (RWH). The main objective of this study was to determine the most commonly effective methods and techniques that have been practiced in the middle-east region to summarize the best methods for rainwater harvesting site selection. These effective common methods of multi-criteria analysis (MCA) were discussed accordingly in this review paper and based on the previous studies the best applicable method was the integration between (MCA) method and the GIS technique. The study employed a method of gathering and recording the main criteria and techniques which were established in the last thirty years. It compared and categorized the main methodologies from previous studies and practices from international organizations and scientific research and identified the most common characteristics and sets of criteria suitable for use in arid and semi-arid regions. The techniques were diverse based on biophysical criteria to methods including socio-economic criteria, precisely in the last two decades. The most effective and significant criteria for suitable site selection of RWH in the arid and semi-arid regions found are: land use/land cover, slope, type of soil, rainfall intensity, streams distant and the cost. The success of RWH selection sites tended to increase when these criteria are measured and based on these criteria.
Open Access
Critical Supply Chain Problems In Contractor - Subcontractor Interface Of Sri Lankan Building Construction Projects
(SLIIT, 2022-02-11) De Silva, P; Panagodage, T. L
As a developing country, construction industry provides considerable contribution to the Socioeconomic growth of Sri Lanka. However, successful completion of a construction project is yet a challenging task. It requires coordination, collaboration and management of different stakeholders with different objectives. While achieving the objectives of a construction project, a proper management of supply chain is vital as improper management of the supply chain impacts negatively on the construction project delivery process. Prior studies have identified several interfaces which impact on the successful project delivery. The mechanism related to contractor-subcontractor interface highly impacts the ultimate project outcome as it is directly linked with the delivery of the project. This study set out to identify the critical supply chain problems in contractor-subcontractor interface in Sri Lankan building construction projects. The study was derived through a mix method approach. Semi structured interviews were carried out among the industry expertise to identify the supply chain related problems. Thereafter, to identify the critical problems of supply chain, a questionnaire survey was carried out among the industry practitioners in the building construction projects. The data was analyzed using Relative Important Index in order to rank and identify the severity of each identified problem in the contractor – subcontractor interface. The study indicates that, using verbal information, lack of reference to the main contract and nonresponsible responses as the critical problems in the Information flow. In terms of the Material flow: deliveries are not according to the plan, poor labour management and noncompliance with material and components are ranked as the critical problems. Delay in payments, back-to-back payments and payment interest charging as the critical problems under the Capital flow. These findings may assist the industry practitioners to identify the criticality and monitor supply chain problems in contractor- subcontractor interface and to minimize them in building construction projects.
Open Access
Cryptocurrency Price Prediction: A Comparative Study using LSTM, GRU and Stacking Ensemble Algorithm for Time Series Forecasting
(SLIIT, 2022-02-11) Ashikul Islam, M. D
Technology has significantly reshaped how humans interact with their tangible and intangible surroundings. Cryptocurrency is considered to be one of the most recent technological inventions which revolutionized how we perceive currencies and their functionality. It has become popular because of its safety, security and anonymity. However, volatility remains one of the major issues with cryptocurrencies to this day. Therefore, the primary aim of this paper is to develop LSTM (Long ShortTerm Memory), GRU (Gated Recurrent Units) and a Stacking Ensemble Learning algorithm that efficiently predicts the price of a cryptocurrency for a given period of time. The predictions are then observed and analysed to determine the comparative performance of the said algorithms.
Open Access
Design and Fabrication of a Novel Hybrid Solar Dryer
(SLIIT, 2022-02-11) Perera, C; Fernando, G; Liyanage, M
A hybrid solar dryer was designed and tested for commercial dissemination of active and passive drying methods over traditional sun drying methods. The proposed dryer employs novel features such as user controllability of the drying parameters and includes sensors and controllers for active monitoring of drying parameters. The functionality of the dryer is broadened by using logic control whereby intermittent drying patterns are introduced to the system for more efficient operation. This paper documents the design calculations and fabrication process of the dryer as well as the results of drying obtained under a controlled environment. 10 experiments have been carried out to assess the limits and potential improvements to the system which yielded satisfactory conditions with a temperature fluctuation of ±1℃ and change in %RH of ±2% at any given temperature within the specified limits. The developed system has been used for drying apples which yielded dried products from an initial weight of 346 grams to a final weight of 55 grams in 5 hours in pure convection and the same initial weight was reduced to 52 grams in 3 hours when operating in solar hybrid mode. The average energy consumption of the dryer was obtained at 300 Watts at uninterrupted solar insolation operation and 224 Watts during pure convective operation, portraying the efficient operation of the system to be eligible to be powered by a solar-powered energy storage
Open Access
Development of Silica-Copper Nanocomposite for Water Purification
(SLIIT, 2022-02-11) Angappan, S; Karunaratne, M; Thambiliyagodage, C
Water pollution is one of the serious concerns across the world at the moment. Industrial wastewater significantly contributes to the negative impacts caused by water pollution. Textile industries discharge large amounts of effluents into water streams with little or no treatment of the discharge because wastewater treatment is an expensive process. Thus, there exists a need for a cheap and effective way to treat textile effluent that contains dyes before being discharged. A high purity silica-based Nano-adsorbent was synthesized by using rice husk as the commercially available main cheap precursor. Copper-loaded silica nanoparticles were successfully functionalized with 3-aminopropyl triethoxysilane (APTES) via the sol-gel pathway to enhance the adsorption performance of organic dyes from textile effluent. The performance of produced Nano-adsorbent was evaluated by using methylene blue as waste adsorbate. As synthesized nanomaterial was characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy, the XRD results confirmed the presence of silicon dioxide (SiO2) and paramelaconite (Cu4O3) as predicted. The FTIR confirmed the presence of Si–O stretching, N-H bending, C–H stretching, Cu–O stretching and O–H bending vibrations thereby suggesting the presence of SiO2, NH2 groups, CH2, Cu4O3 and physisorbed H2O. The optimum conditions for pH and adsorbent dosage were successfully evaluated for the adsorption process. The optimum pH at which the nanomaterial performed best was at pH 4. The optimum mass of the adsorbent that gave maximum adsorption performance was 20 mg. Kinetic studies revealed that the experimented data was in better correlation with pseudo-second-order kinetics. The outcome of this project would be of interest to textile industries looking for a cheap and effective way to treat textile wastewater
Open Access
Domestic Energy Saver
(SLIIT, 2022-02-11) Kumarasinghe, R; Abhayasinghe, N
Most of the activities in the modern world are heavy power consumers. Therefore, wasting of power is identified as a critical factor which is badly impacted the environmental and economic growth. Using electrical appliances such as ceiling fans and bulbs in the commercial and domestic environment unnecessarily is identified as a main way of wasting power. As a solution, this paper proposes the designing and producing of a power saving device for ceiling fans and bulbs. Variables such as room temperature, light intensity and the number of people present in the location were considered as parameters to control ceiling fans and bulb automatically, so as to save power by changing the speed and turning off when not necessary. This device is consisting of six main units namely a main control unit using Arduino Nano microcontroller, bidirectional visitor counter unit using two Passive Infrared motion sensors, temperature and light intensity measuring unit using a LM35 temperature sensor and a light dependent resistor sensor, an output display unit using 1604 LCD display, ceiling fan controller unit using a fan regulator that was constructed using two RC circuits, a relay module and a bulb controller unit. Ceiling fan speed and the delay time to switch off the appliances is controlled using a fuzzy logic controller. Inputs of the fuzzy logic controller are temperature difference with the set temperature, rate of change of temperature difference within a five-minute interval, difference of the number of people inside the location with the set number of people and the rate of change of number of people within a five-minute interval. It was observed that, for the test cases, an average of 318Wh per day could be saved from a single bulb and a ceiling fan while avoiding unnecessary usage of appliances.
Open Access
Effective Waste Management Strategies of Bentonite in Sri Lanka
(SLIIT, 2022-02-11) Guruge, K; Coomasaru, P
One of the greatest challenges of Bentonite usage in construction industry is, managing the wastage created in sites thus, it has to be given attention. Therefore, the study would be conducted focusing on the domestic piling construction sites and the process followed by them. Although it is a chemical, it is recognized to be safe for both the environment as well as mankind in an ecological and health protection perspective. However, a proper disposal method in order to reduce the further issues as excessive waste in sites is needed. Therefore, this study aims to explore an effective method regarding the waste management strategies for Bentonite in Sri Lanka. The objectives of the study are, identifying the wasting methods of Bentonite, identifying causes of disposing Bentonite and determining the most suitable method for Bentonite disposal. Data for the objectives one and two were collected through a literature survey and analyzed by using NVivo which was validated using a questionnaire by majority of 5-10 years experienced professionals aligning to mixed method approach. Data for the third objective was found by aegis of the same questionnaire. Noticeably, it was validated through interviews by the industry experts with more than 30 years of experience. The study found that, site conditions are the most relatable reason for the Bentonite waste. Apart from that ‘weather’ and ‘manual handling errors’ can be additional reasons for the wastage. Moreover, most sites consider either ‘when the slurry forms into a cake’ or ‘silos are full’ as the causes for disposal. Furthermore, it has identified that the majority of sites dispose the waste to disposable lands using bowsers as of the disposal method after reusing 3-4 times. The suggested method appears to be cost effective and efficient in comparison to the others. Furthermore, it can be rather safe and environmentally friendly.
Open Access
Estimation of Person-Kilometers of Travel in Sri Lanka
(SLIIT, 2022-02-11) Gunathilaka, S; Amarasingha, N; Lakmali, M; Perera, C
Person Kilometers of Travel (PKT) provides all trip information of an individual including trips by motorized, non-motorized, public or informal public transport modes. Estimating PKT in developing countries seems much important as PKT is one of key parameters in transport planning and policy making. Since PKT focuses on an individual, it is influenced by socio demography of the person. However, timely PKT is not estimated by relevant agencies of Sri Lanka. The study focused on estimating PKT in Sri Lanka with travel mode distributions. A paper-based travel survey was conducted over all administrative districts in Sri Lanka for collecting trip information and socio demographic factors of people. 9,012 people participated in surveys resulting a 77.62% response rate. Respondents were asked to provide information of their trips in a typical week, in special holidays and seasons, information on travel modes and their socio demographic information. Data obtained from surveys were aggregated to annual level and weighted in order to obtain PKT/person/year under each socio demographic category. Weightages were estimated using census data in each administrative district. The study came up with important findings; weighted PKT estimations and travel mode distributions in each administrative district. Further, statistical comparisons of PKT estimates among different socio demographic groups and districts were conducted using One-Way Analysis of Variance (ANOVA) test. These findings were key contributions to the existing literature in the country.
Open Access
Experimental investigation of concrete-filled and bare 6082-T6 aluminium alloy tubes under in-plane bending
(SLIIT, 2022-02-11) Kamaris, G. S; Gkantou, M; Kansara, K. D; Bin Al, S
The application of aluminium alloys in construction sector is increasing owing to their excellent corrosion resistance, light weight and attractive appearance. However, one of the main disadvantages of aluminium alloys is the low elastic modulus, which may cause a stability issue in aluminium structural members. The performance of aluminium tubes can be improved by filling concrete within them. Research on the flexural behaviour of concrete-filled aluminium alloy tubes is limited. This paper presents an experimental study on the behaviour of square and rectangular concrete-filled and bare aluminium tubular sections subjected to in-plane bending. Total 20 beams were tested, including 10 concrete-filled aluminium tubes (CFAT) and 10 bare aluminium tubes (BAT). The hollow aluminium tubes were fabricated using 6082-T6 alloy and filled with 25 MPa cylinder compressive strength concrete. The material properties of aluminium were measured by tensile test of coupons. It is shown that the flexural strength, stiffness and ductility of square and rectangular BAT flexural members was remarkably improved by the infilled concrete and the improvement is more pronounced for the thinner aluminium sections. Due to absence of design standards for CFAT beams, in this study the design rules available for concrete-filled steel tubular flexural members in the Eurocode 4 are considered by substituting the mechanical properties of steel with those of aluminium alloy. It is demonstrated that the proposed design rules provide good predictions of the flexural capacity of CFAT.
Open Access
Fire Safety Performance of High-rise buildings in Sri Lanka
(SLIIT, 2022-02-11) Perera, H. D. N. L; Allis, C
Fire safety is the most critical aspect of high-rise building safety. As human life is essential than other aspects, analysis of a reliable building fire safety performance is more critical than ever. Whenever an actual fire incident occurs, the active firefighting systems in the building would be activated first. As a result, it is necessary to identify the operation of active firefighting systems as well as proper service and maintenance of the systems. The research problem was identified as, people tend to fulfill the minimum fire safety requirements imposed by regulations. Therefore, the condition of fire safety performance in most highrise buildings are very poor. The aim of this research is to identify suggestions to improve the fire safety performance in high-rise buildings in Sri Lanka. Consequently, three objectives have been established to fulfill the research aim. In the first objective, building design features, human behaviors, equipment failures, and underperformance of fire regulations are highlighted as contributing factors to building fire events. The second objective evaluates fire safety precautions implemented in high-rise buildings, such as alarm activation, communication and evacuation procedures, service and maintenance periods of live fire systems, and fire evacuation drills. In the third objective, suggestions to improve the fire safety performance in high-rise buildings are recognized as, maintaining proper coordination between the fire brigade and building fire maintenance department at all times. Since the interpretivism philosophy used in this inductive qualitative research, the data was collected through conducting ten interviews with professionals who are primarily engaged with achieving reliable fire safety performance in high-rise buildings. In conclusion, recommendations such as, establish a coordination center to maintain proper coordination with fire brigade, air force and building maintenance staff and introduce a trained air force squad with helicopters and firefighting equipments can be implemented in Sri Lankan high-rise buildings
Open Access
Impact of Variable Travel Time on the Solution of Vehicle Routing Problem: A Case Study of Bangkok
(SLIIT, 2022-02-11) Piantanakulchai, M; Saum, N; Shah, S
In the logistics industry, it is essential to have optimized vehicle routes for cost-effectiveness and customer satisfaction. However, most conventional studies on vehicle routing problem (VRP) do not consider the variation in travel time, leading to nonoptimal routes. This study shows the importance of variation in travel time for different times of the day and different days of the week by comparing the optimization results of vehicle routes for constant travel time and variable travel time. Two different scenarios were considered for Bangkok city, Case-1, where customers are scattered across the city, while Case-2, where customers are concentrated on a small area. It was concluded that up to 27.59% error in travel time could be obtained with an average of 12% for Case-1. At the same time, a maximum 30.85% error in travel time can be obtained with an average of 7% for Case-2. Therefore, it is necessary to consider time-dependent travel time in urban logistics route planning in Bangkok. This study also put forward a method to collect travel time data of different origin-destination pairs for different times of the day and different days of the week that can be used by any logistics company.