Browsing by Author "Ranawaka, RKTK"

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item: Conference-Abstract
Decade of action for road safety: trends in road accidents, Sri Lanka
(Department of Civil Engineering, University of Moratuwa., 2019-09) Ranawaka, RKTK; Pasindu, HR; Pasindu, HR
At present, nearly eight people die due to road accidents each day in Sri Lanka. This amounts to over 3000 fatalities per annum. This is an increase of 35.2% when compared to the fatalities in the year 2008. During the same period, the registered number of vehicles has increased by 113%. With the rapid motorization and decrease of public transport usage which has taken place over the last decade, new trends in road accidents have emerged in Sri Lanka. The study used accident data from 2008-2017, to identify how the accident types and patterns have changed over the period. In the year 2008, most of the accidents have happened in roads classified as urban, with a percentage of 53%. By 2017, 53% of the accidents have happened on roads classified as rural. Within the period from 2008 to 2012, most of the accidents have happened between 16:00-18:00. The trend has shifted to the time period of 18:00-20:00 from 2013 onwards. During the study period, the motorcycle was the highly exposed vehicle type to accidents. Motorcycles account for 23% of the total vehicles, engaged in accidents in the year 2008. It has increased up to 27% of the total vehicles engaged in accidents in the year 2017. Most numbers of motorcycles involved accidents are pedestrian-motorcycle accidents. The percentage of motorcycle-car accidents has increased from 10% to 14% from the year 2008 to 2017. Most numbers of three-wheelers involved accidents are three wheeler-motorcycle accidents. The percentage of three wheeler-car accidents has increased from 15% to 21%, when considering three-wheeler involved accidents. The age group with the highest number of casualties is 21-30 years when considering both motorcycle and three-wheelers involved accidents. Pedestrian accidents have increased by 10% when compared to the year 2008. Among pedestrian involved accidents, pedestrian-motorcycle accidents have the highest rate in each year. The highest exposed age group for pedestrian related accidents is 41-50 years each year. It is generally around 15% of the total pedestrian accidents each year. Among lorry involved accidents, lorry-motorcycle accidents have the highest rate in each year. Lorry-motorcycle accidents have increased by 6% when compared to the year 2008. In the year 2008, most of the lorry related accidents have happened by lorry drivers within the age group of 21-30 years, which is 30% of all lorry involved accidents. By the year 2017, the trend has shifted to the age group of 31-40 years, which is 36% of all lorry involved accidents. The study could capture two weaknesses in the accident reporting system in Sri Lanka. 99% of the accidents have been recorded without identifying probable roadway and vehicle pre - crash factors. Results of this study will be useful input for policymakers to develop effective long term and short-term strategies to reduce road accidents.
item: Conference-Full-text
A framework for selecting safety treatments for rural roads
(Springer, 2021) Ranawaka, RKTK; Pasindu, HR; Dias, TWKIM; Pasindu, HR; Bandara, S; Mampearachchi, WK; Fwa, TF
Road safety is a vital element of the road’s overall function, which is often neglected in decision-making for road maintenance management. As a result, the safety issues, especially in rural roads, remain without funding to implement the necessary countermeasures. One constraint faced by local authorities is the lack of analysis tools to select appropriate safety treatmentswithin the available budget. This study presents a methodology to logically determine the safety treatment criteria for a selected road to increase the safety performance at project level. The decisions regarding the safety treatments are taken based on a linear programming model which optimizes the safety performance of the selected road. Cumulative Safety Index (CSI) represents the safety performance of the road, which is determined based on the prevailing issues on that road. The model comprises the objective function by which maximizes the safety performance of the selected road concerning the number of prevailing safety issue types. This model is used to identify the optimal safety treatment scheme for the road chosen, ensuring prevailing safety issues of the road are effectively addressed. The objective function consists of the Initial CSI of the selected road and the safety improvement after treating relevant issue type coupled with a binary decision variable. This model can also be considered an input to road asset management systems where multi-objective optimization (MOO) models maximize the network pavement condition and maximize overall network safety performance.
item: Conference-Full-text
A framework to incorporate safety performance for low volume roads in pavement management systems
(IEEE, 2020-07) Sandamal, RMK; Ranawaka, RKTK; Pasindu, HR; Edussooriya, C; Weeraddana, CUS; Abeysooriya, RP
Low volume roads provide the connectivity between residential, agricultural areas and the national road network. Those are especially critical in rural areas to provide accessibility for the community to fulfill their social and economic needs. Low volume roads account for nearly 61% of the road network length in Sri Lanka while the rapid motorization take place, it is expected the traffic volume on these roads will increase significantly in the future. However, some of these roads have not been constructed and maintained according to the standard design guidelines, and due to that major safety issues are raised on such roads. This study focusses on the main causal factors of low volume road accidents and a methodology developed to evaluate the safety performance based on the roadway characteristics. Further, a framework is proposed to incorporate safety performance in decision criteria especially in the multi-objective optimization process of pavement management systems.
item: Article-Full-text
Incorporating road safety Into rural road network pavement management
(Taylor & Francis, 2021) Pasindu, HR; Ranawaka, RKTK; Sandamal, RMK; Dias, TWKIM
Rural roads play an essential part in a country’s road network providing connectivity between the rural communities and the national roads. However, most of these roads are not maintained efficiently and safety issues are often not prioritised since pavement conditions are prioritised, especially in developing countries. Lack of reliable crash data, road condition monitoring regime are often cited as reasons. This study proposes a methodology to incorporate road safety performance in rural roads in maintenance planning using a multi-objective optimisation approach. Road safety performance is defined in terms of the Cumulative Safety Index (CSI), computed based on the severity, exposure, frequency of safety issues, identified in road safety audits. Safety performance and pavement condition-related indices such as International Roughness Index (IRI), pothole number, are included in the optimisation analysis. It comprises two objectives: minimise network IRI, and minimise network CSI. Applicability of the developed model has been demonstrated from the illustrative example of a rural road network. Results shows that roads with safety issues can also be prioritised in budget allocation while ensuring the network level pavement condition can be maintained at a reasonable level. This methodology offers a simplified approach to incorporate road safety issues in rural road PMS.
item: Article-Full-text
Incorporating road safety Into rural road network pavement management
(2022) Pasindu, HR; Ranawaka, RKTK; Sandamal, RMK; Dias, TWKIM
Rural roads play an essential part in a country’s road network providing connectivity between the rural communities and the national roads. However, most of these roads are not maintained efficiently and safety issues are often not prioritised since pavement conditions are prioritised, especially in developing countries. Lack of reliable crash data, road condition monitoring regime are often cited as reasons. This study proposes a methodology to incorporate road safety performance in rural roads in maintenance planning using a multi-objective optimisation approach. Road safety performance is defined in terms of the Cumulative Safety Index (CSI), computed based on the severity, exposure, frequency of safety issues, identified in road safety audits. Safety performance and pavement condition-related indices such as International Roughness Index (IRI), pothole number, are included in the optimisation analysis. It comprises two objectives: minimise network IRI, and minimise network CSI. Applicability of the developed model has been demonstrated from the illustrative example of a rural road network. Results shows that roads with safety issues can also be prioritised in budget allocation while ensuring the network level pavement condition can be maintained at a reasonable level. This methodology offers a simplified approach to incorporate road safety issues in rural road PMS.