TRF - 2012

Permanent URI for this collectionhttp://192.248.9.226/handle/123/17949

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Browsing TRF - 2012 by Subject "Daytime visibility"

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    item: Conference-Abstract
    Study the variation of visibility of road marking with time due to traffic in urban national roads in Sri Lanka
    (Department of Civil Engineering, University of Moratuwa., 2012-07) Sumendra, MAP; Bandara, JMSJ; Pasindu, HR
    It has long been recognized that visibility of road marking is essential for efficient traffic flow and road safety. There are complaints of that the road marking in many national road of Sri Lanka have poor visibility in daytime and nighttime. The major reason for the poor visibility is low reflection levels of road markings. The performance of the road marking is affected due to embedment of glass beads, water on road way, drivers eyesight ,position and quality of headlamps, road surface debris etc. Retro-reflectivity is the ability of a road marking to reflect light from a vehicles head lights to the driving position of a vehicle. It will be determined by the amount of glass beads spread on the line and amount and quality of glass beads included in the body of road marking. Main objective of this research is to understand the variation of visibility of road marking with time due to traffic and other environmental parameters, identify the optimum frequency of time for remarking in urban roads and introduce a guide line for remarking of road marking while integrating as a program to a road database in highway management tool as a future implementation. Preliminary measurement carried at some high volume traffic roads in western province that considerable amount of reduction of reflectivity with time due to traffic. For example Galle road (A002) that has ADT of 77450 the reflectivity has changed by 46% after 9 months. Base line road (M001) has ADT of 90645 the reflectivity has changed by 62% after 6 months. Kollupitiya -Sri Jayawardanapura road (A000) has ADT of 79490 the reflectivity has changed by 69% after 12 months. The rate of reduction of reflectivity (RL per day) for Galle road (A002), Base line road (M001) and Sri Jayawardanapura road (A000) are 0.24, 0.48 and 0.26 per day respectively. IS EN 1436 and SLS 1384 introduces specifying criteria for yellow and white road markings .In IS EN 1436 the retro reflectivity value is given as 100mcd/m2 / lux for dry white road markings and in SLS 1384 this value is given as 70mcd/m2 / lux. A relationship between the reduction of reflectivity and traffic and road environment parameters to be developed based on the reflectivity measurements.
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    item: Conference-Abstract
    Use of GIS to identify alternative traces for railway planning & development
    (Department of Civil Engineering, University of Moratuwa., 2012-08) Wickramarathne, K; Bandara, S; Pasindu, HR
    The railway transportation is a one of the energy efficient transportation mode all around the world, as its capability of loading & transporting large amount of passengers and goods economically & safely. In the British colonial era, the railway transportation has been introduced in Sri Lanka, to transport the productions of plantations such as coffee, coco, tea, rubber, coconut, spices & etc, to the port, from up country and all around the island. With the development of new and faster roads forming in to a well connected network and introduction of efficient cars, buses and trucks, railway modal share has decreased. Today there is a need to introduced new railway lines that are faster and also forming a well connected network. Physically, the speed of a train, depend on curvature & gradient of the track. Hence it is important to identify traces that satisfy speed requirements to compete with road traffic. When developing new rail line or roads it is mandatory to consider reasonable alternatives prior to selecting the final trace. With the limited amount of maps and other resources available one cannot spend lot of time to identify possible alternatives using land and field surveys, maps & other primary surveying equipments, when the railway planning & construction phase in Sri Lanka in the past. The paper present an attempt made to use GIS tools such as Spatial Analysis, 3D Analysis, etc to identify possible alternative traces for detail studies using minimum map data available along with available satellite images.