TRF - 2022

Permanent URI for this collectionhttp://192.248.9.226/handle/123/20016

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item: Conference-Full-text
Demand-based roadside parking control strategy for a main road corridor
(Department of Civil Engineering, University of Moratuwa, 2022-12) Dissanayake, M; Gamlath, I; Bandara, S; Perera, HLK
Overcrowding in parking lots near high-demand locations is common in any main urban road, where parking demand often exceeds supply and parking spaces are distributed unevenly. This study aims to develop an effective roadside parking control methodology and strategy using the case study area of the Galle Road Corridor in Colombo, Sri Lanka. To accomplish this objective, it is necessary to identify various parking management strategies, identify parking fee methods and monitoring tools that are being used. In addition, the parking demand and supply on the selected section of the road are required. A single transportation corridor in an urban setting was studied, focusing on light and medium-duty vehicles. Instead of implementing a single uniform parking fee system for the entire region, we are proposing to implement a method where the parking fee varies based on the location and time of day so that demand can be distributed to less congested areas. Parking fees will be decided based on the above criteria. The methodology was developed using data such as parking location data and parking time data from the Colombo Municipal Council (CMC). Furthermore, the number of parking spaces was compared to what is currently being collected through Google Maps. The Galle Road section between Kollupitiya and Wellawatta was divided into 13 zones, and parking usage was analyzed by identifying demand, rush hours, and day variations of parking using CMC parking usage data. Following that, a physical survey was conducted to verify the past data that had been analyzed. The use of parking spaces during the day, as well as the vehicle type of parking vehicles, was monitored in the selected sections. Then identify, the pattern between those data and high, medium and low-demand sections was identified based on the time of the day and day of the week. Using CMC parking usage data, spot demand and parking variation by time and by day were identified. High parking was observed between 12.30 pm and 1.30 pm and 6.30 pm to 7.00 pm in the section from Pentrive Gardens to 5th Lane, as well as excess parking in the Alfred House Gardens to Bagathale Road section. As a result, pricing mechanisms can be used to distribute parking. The parking price and parking arrangements were adjusted according to the demand of the location. As a result of these changes, a new smart strategy for managing public parking in urban areas, such as a mobile app and features, was suggested, allowing for more efficient use of parking spaces in the city.
item: Conference-Abstract
Demand-based roadside parking control strategy for a main road corridor
(Department of Civil Engineering, University of Moratuwa, 2022-12) Dissanayake, M; Gamlath, I; Bandara, S; Perera, HLK
Overcrowding in parking lots near high-demand locations is common in any main urban road, where parking demand often exceeds supply and parking spaces are distributed unevenly. This study aims to develop an effective roadside parking control methodology and strategy using the case study area of the Galle Road Corridor in Colombo, Sri Lanka. To accomplish this objective, it is necessary to identify various parking management strategies, identify parking fee methods and monitoring tools that are being used. In addition, the parking demand and supply on the selected section of the road are required. A single transportation corridor in an urban setting was studied, focusing on light and medium-duty vehicles. Instead of implementing a single uniform parking fee system for the entire region, we are proposing to implement a method where the parking fee varies based on the location and time of day so that demand can be distributed to less congested areas. Parking fees will be decided based on the above criteria. The methodology was developed using data such as parking location data and parking time data from the Colombo Municipal Council (CMC). Furthermore, the number of parking spaces was compared to what is currently being collected through Google Maps. The Galle Road section between Kollupitiya and Wellawatta was divided into 13 zones, and parking usage was analyzed by identifying demand, rush hours, and day variations of parking using CMC parking usage data. Following that, a physical survey was conducted to verify the past data that had been analyzed. The use of parking spaces during the day, as well as the vehicle type of parking vehicles, was monitored in the selected sections. Then identify, the pattern between those data and high, medium and low-demand sections was identified based on the time of the day and day of the week. Using CMC parking usage data, spot demand and parking variation by time and by day were identified. High parking was observed between 12.30 pm and 1.30 pm and 6.30 pm to 7.00 pm in the section from Pentrive Gardens to 5th Lane, as well as excess parking in the Alfred House Gardens to Bagathale Road section. As a result, pricing mechanisms can be used to distribute parking. The parking price and parking arrangements were adjusted according to the demand of the location. As a result of these changes, a new smart strategy for managing public parking in urban areas, such as a mobile app and features, was suggested, allowing for more efficient use of parking spaces in the city.
item: Conference-Abstract
Impact of autonomous vehicles on road safety in heterogeneous traffic conditions
(Department of Civil Engineering, University of Moratuwa, 2022-12) Chathuranga, K; Bandara, S; Perera, HLK
Autonomous vehicles (AVs) can sense their environment and operate without human involvement. These AVs are implemented with a lot of Advanced Driver Assistance Systems (ADASs). Six levels of driving automation have been defined by the Society of Automotive Engineers (SAE), ranging from Level 0 (no driving automation) to Level 5 (full driving automation). Most of the ADAS features can be seen on vehicles belonging to the SAE level 2 or above. A few features, such as Lane Centering (LC)/ Lane Keeping Assist (LKA), Adaptive Cruise Control (ACC), and Automatic Parking, are categorized at level 2. The majority of vehicles in Sri Lanka belong to levels 0 and 1, and some vehicles that belong to level 2 are also available. However, vehicles that belong to Level 3 or above are hardly seen. Autonomous vehicles and ADAS features are fairly new subject areas in the local context. Sri Lanka does not have a developed road network that can fully accommodate autonomous driving. Further, the vehicle composition on Sri Lankan roads is very different compared to that in developed countries, as there is a higher percentage of light vehicles such as three-wheelers and motorcycles. Despite the above differences and challenges, for a country with high congestion in urban areas, many advantages can be obtained from facilitating an A system. These benefits include accident reduction, improved fuel economy, increased lane capacity, reduced travel time, etc. It is proven that automated vehicle technology could result in greater efficiency in fuel/time savings and a significant reduction in congestion without the need for additional capacity. The main purpose of this study is to study the effect of the different ADAS categories and ADAS combinations against the identified accident types to compare the effectiveness of the safety features in the Sri Lankan context. In addition to that, by identifying theoretical and practical road safety issues in a hybrid system where different levels of ADAS vehicles are present, the road safety outcomes can be analyzed with respect to the autonomous levels and the different percentages of each type. Subsequent to the identification of safety features and ADAS categories, accident types, and the causes of the accidents, an organized database was created. An online survey form was developed to gather vehicle and accident details from the public. A descriptive introduction and a set of identified accident categories were included in the survey form so that respondents could provide their vehicle details along with the ADAS features and past accident details. Responses for 200+ vehicles were collected, including around 40%responses with details about one or more accidents that have happened during the last five years. The second stage of this study was to focus on secondary data sources such as accidents recorded by police and the expressway management division of the Road Development Authority. Vehicles involved in fatal accidents were filtered out, considering only cars manufactured after 2005 to accommodate different autonomous levels for accidents recorded in police reports for 2017. Expressway accident records available from 2016 show that the number of fatal + grievous + non-grievous accidents in total is around 100 per calendar year. Around 250 cases were chosen for further study after sorting them by the severity of the accident. For selected accidents from expressway reports and police reports, the vehicle model and the manufactured year were identified for each vehicle using the database available on the Sri Lanka Motor Traffic Department website. As the next step, accident type combinations and the corresponding ADASs were categorized. Potential accident reduction percentages for each ADAS-accident type category were found. The results show that most of the time, these features individually have the potential to reduce the severity of the accident by around 15%. When two or more ADAS features work together, not only reduces the severity but high accident prevention percentages can also be achieved. Two scores for the safety level and the autonomous level were then obtained by assigning weights to the corresponding ADAS features. In the absence of any detailed studies, those assumed weights were derived by studying the impact that each ADAS can have according to the results of the above study done for ADAS and relevant crash patterns. According to the selected data set and the assigned weights, it is found that the average safety score of the Sri Lankan context for urban, suburban and expressway road sections is 10.7%, and the autonomous level is only 1.8%. Finally, considering the results and the current vehicle composition, advanced driver assistance features were categorized and lined up in the order of being the most effective in the Sri Lankan context.
item: Conference-Full-text
Impact of signalized pedestrian crossings near un-signalized intersections
(Department of Civil Engineering, University of Moratuwa, 2022-12) Priyankara, N; Jayasooriya, N; Bandara, S; Perera, HLK
Intersection control is the major function of the traffic flow. Its values increase when traffic flow becomes more severe. However, road authorities use some ad hoc methods to control intersections to reduce costs. Signalized pedestrian crossings near unsignalized intersections are one of the methods used by road authorities to control the intersection. This kind of arrangement can be found in Colombo and its suburbs. Some of the major issues observed at signalized pedestrian crossings near un-signalized intersections are as follows: Drivers coming from a by-road could not see the main road signal indications; vehicles from by-roads have to stop in the middle of the road due to vehicles queuing up in the merging lanes. In addition to the above, some other issues related to pedestrian signal operation are also identified. In situations where a push-button system for pedestrians is available, a significant delay for motorists can be experienced when the pedestrian flow is high. It creates delays and results in long queues. Though there are advantages with respect to pedestrian safety and partial control of intersections, some of the abovementioned issues result in many disadvantages as well. Therefore, this study aimed to evaluate the effectiveness of signalized pedestrian crossings near unsignalized intersections on both traffic and pedestrian movements. Five different intersection and signal arrangements are identified, covering four-way and three-way intersections, and issues related to each arrangement were identified based on the existing literature. A total of ten locations on Galle Road (A02) and Colombo Horana Road (B84) were selected for the analysis process. Geometric data of the intersection, manual and/or vision-based vehicle and pedestrian counts and queue lengths and details about the pedestrian phasing are collected during the data collection. Queue lengths and vehicle delay times, and safety considerations were analyzed to evaluate the effectiveness. These analysis results are to be validated using the open-source microsimulation software SUMO. It is found that it is better to go for a fully signalized intersection control for situations where pedestrian crossings are to be located on both sides of the minor road(s). For three-way junctions with single pedestrian crossings, it is better to locate the crossing at least 20 m from the intersection.
item: Conference-Abstract
Model to identify the optimum feeder bus route for an urban rail transit station based on capacity of feeder buses
(Department of Civil Engineering, University of Moratuwa, 2022-12) Kanagasingam, U; Bandara, S; Perera, HLK
Urban rail transit systems are very cost-effective as compared to other transit modes though they cannot provide wider service coverage for the users. Feeder buses play a major role in filling the service gaps left by urban rail transits. The effectiveness of the feeder bus of an urban rail transit depends on its bus route length, frequency, capacity, and travel time. As all parameters are interconnected, changing one will impact others. This study discusses a mathematical model to identify the optimum feeder bus route for an urban rail transit station. The effectiveness of the feeder bus can be optimized by reducing the total cost of /the feeder bus service. The total cost includes both the user's costs and the operator's costs. Several service parameters influence the components of the total cost equation. The parameters discussed in this study are route length, frequency, bus capacity, travelling and waiting times, walking distance and passenger behaviour characteristics. Assumptions were made regarding passenger behaviour because it varies for every passenger according to several factors. For example, bus stop spacing and maximum walking distances were assumed to be constants, and all roads were assumed to be in grid mesh format. First, a simple model was developed that has one trip generated to the railway station. Then it is further extended to one bus stop from which several trips are directed to a railway station. After that, a model that has several bus stops in a feeder bus route that connects to a railway station was developed. From there, an optimized many-to-one feeder service model was identified. In different instances, there will be changes in the values of the parameters in the mathematical model. By using the mathematical model, we can check which set of parameters best suits the optimized route. This can be further extended to a many-to-many demand model that has several railway stations and bus stops that are interconnected with each other.
item: Conference-Abstract
Multi-criteria analysis to prioritize user expectations at traffic signal
(Department of Civil Engineering, University of Moratuwa, 2022-12) Saranjan, P; Bandara, S; Gamalath, I; Perera, HLK
Traffic signals regulate complex traffic situations and minimize conflicts to enhance the safety of all road users. Further, traffic signals aim to provide an orderly flow of traffic to minimize delays. However, poorly designed traffic signals can result in user inconvenience. Discrepancies between road users at traffic signals can have an impact on the smooth flow of traffic and the effectiveness of travel. The objective of this study was to identify and prioritize the user expectations at traffic signals considering different user groups, such as drivers, pedestrians and passengers, to provide a resource for agencies that are responsible for implementing and managing traffic signals. From the literature review, three main categories of issues and their relevant parameters concerning traffic signals were identified: safety, delay and ease of use. Key parameters identified for safety are conflicting turning movements, red light violations, jaywalking, and lightings at the pedestrian crossing at night time. Effects of the near-side bus stop, the higher number of intersecting approaches at signals, number of heavy vehicles, peak hour and on-street parking were identified as delay-related parameters, while the visibility of traffic signals and countdown timers were identified as ease of use, related parameters. These issues arise because of the conflicts of the behavioural and expectation difference among different road users. A survey was conducted to understand the priorities for the above-identified categories and their parameters for different road users. The questionnaire is distributed online and shared among different groups of people via social media. This study obtained responses from 357 participants via the online questionnaire. A scoring method was used to identify the participant's expectations on each parameter. The weightage of each parameter was calculated according to the score given for each parameter by participants. Collected data were analyzed using the multi-criteria analysis. The final weightage values obtained from the analysis are used to prioritize the parameters. From the analysis, it was found that all road users prioritize their safety more at the traffic signal than delay and convenience of use. Further, road users are giving slightly higher importance to ease of use than delay. Drivers and passengers give more importance to red-light violations, jaywalking and high speed at the end of the amber period for the safety parameter. According to drivers, far-side bus stops and noise from vehicles have the least priority. Pedestrians stated that the lighting at the pedestrian crossing (for night-time use) and conflicting turning movement of vehicles are having the highest impact. Pedestrians are given the least priority for longer cycle times and emissions from vehicles. Further, expectation differences in each subset of groups were analyzed by considering age, gender and mode of travel.

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Browsing TRF - 2022 by Author "Bandara, S"