TRF - 2014

Permanent URI for this collectionhttp://192.248.9.226/handle/123/17951

Browse

Now showing 1 - 7 of 7

item: Conference-Abstract
An approach to estimate the vehicle travel time on un-signalized two lane roads
(Department of Civil Engineering, University of Moratuwa., 2014-08) Galappaththi, GS; Perera, L; Bandara, JMSJ; Pasindu, HR
Reliable travel time estimation for a given route is important in transport planning. Even though the developed countries in the world have different methods of forecasting travel time from a simple road network to a complex transport network, local availability of such methods are lacking mainly due to the inadequacy of data or investments for the implementation. Several qualitative factors such as geography, weather, time of travel etc. and quantitative factors such as road geometry, traffic flow etc. affects the time taken to travel. But the fluctuations in these factors cause significant changes in the travel time. There are no any travel time estimation models currently used in the country during the planning stage or in the monitoring stage to check the efficiencies or enhance the current conditions of the road network. The objective of this study is to develop a relationship using different land use patterns to estimate the travel time on three leg intersections accurately for road links in order to build a model for travel time estimation on un-signalized two lane roads. Trip attraction and trip generation in regions depends on the land use pattern of that area and cause the differences in vehicle travel. Due to this reason this study focus to develop a travel time estimation technique that can be implemented by considering different land use types such as residential, commercial, industrial, accessibility, agricultural/forest coverage etc. Two lane road sections of three national highways in Sri Lanka; Peliyagoda-Puttalam road (A03), Colombo-Kandy road (A01), Ambepussa-Trincomalee road (A06) were considered for this study to associate the different land use types, different vertical and horizontal alignments and its correlation with vehicle travel times. For this study, travel time data along the roads was collected during peak hours of the day using a GPS (Global Positioning System) data logger. Time taken to travel, Travel length, presence of commercial length, additional number of access roads ( access roads present other than intersection connection roads) and number of schools or temples in the intersection were collected for each intersections. Multivariate regression analysis is used to develop the relationship between the land use pattern and the travel time. The model showed a significant positive correlation with Travel length and Commercial length present.
item: Conference-Abstract
Assessing the appropriateness of providing separate openings for U-turns at signalized intersections
(Department of Civil Engineering, University of Moratuwa., 2014-08) Jayasooriya, N; Perera, L; Bandara, JMSJ; Pasindu, HR
Generally the right turns along with the U turns is one of the main contributory factors for the delays at signalized intersections. If any intersection is experiencing a high amount of U turns, the effective time that can be allocated for the other phases and directions would get reduced. Therefore if time given for the U turns can be reduced at the intersection, sufficient amount of capacity improvement can be obtained and thus the congestion at the intersection can be reduced. The concept of providing separate openings for U turns has been experienced in the world, with concepts like super street junctions or j junctions, but no significant research was conducted based on the applicability of such in the Sri Lankan context. With respect to that, the objective of the research was to assess the appropriateness of providing separate openings for U turns at signalized intersections in the local context. Further it is needed to develop a guideline to be followed when introducing separate openings for U turns. The Orugodawatta junction was considered as a case study, whereas high number of U turns are observed at the junction for North bound direction and a 12 hour traffic flow count was taken on an average week day along with a video recording. Based on the basic analysis it was obtained that, 5% of the vehicles travelling North bound Direction are U turns which is quite high for a normal intersection. Further, it was found that out of all the vehicles traveling in North bound Direction, 17% of the vehicles can be considered as either right turns or U turns. On the other hand, out of all the right turns occurring from south to east direction, 25% of the right turns are actually U-turns, which is very significant. It is also observed that on average a right turn takes nearly 1 second and a U turn takes nearly 3 seconds. Blink 2005 software, which is specifically designed for traffic signal designs is used for further analysis. A comparison is done based on the Cycle time between the two instances, with and without the separate opening and it was obtained that the cycle time at the present situation is 291 seconds and with the introduction of the Separate opening the cycle time can be reduced to 240 seconds. Further, cycle time variation for different proportion of U turns are also calculated. Based on the results obtained it can be concluded that more than 10% of the cycle time reduction can be obtained when the U turns are more than 15% of the total right turns occurring at a signalized intersection, by eliminating the U turns and introducing separate openings for U turns.
item: Conference-Abstract
Criterion for selecting appropriate rapid transit technology for Colombo
(Department of Civil Engineering, University of Moratuwa., 2014-08) Geethanga, GGS; Bandara, JMSJ; Pasindu, HR
Traffic congestion is a condition on road networks that occurs as use increases and is characterized by slower speeds, longer trip times, and increased vehicular queuing. As demand approaches the capacity of a road (or of the intersections along the road), extreme traffic congestion sets in. Traffic congestion contributes to waste of time and money every second. Many developed/developing countries find solution for the traffic congestion at roads with the help of rapid transit systems. Rapid transit systems that are widely in use can be dividing in to four major categories; Mass rapid transit (MRT), Light rapid transit (LRT), Monorails, Bus rapid transit. (BRT) The main objective of this research is to find a criterion for selecting most suitable rapid transit system for Colombo Metropolitan Region from among the above four types. The study consists of collecting user preference based on a questionnaire survey, evaluating different systems based on considering land availability, passenger demand, road network system, passenger transfer from other modes & environmental issues, and calculating costs & benefits for each rapid transit system. A case study for Battaramulla corridor is presented. The questionnaire collects from the passenger who travels the Battaramulla-Fort corridor. This road section is highly congested at peak time and it will be increase at future due to administration city will become Sri Jayawadanapura Kotte. Hence it is essential to give proper solution for the increasing traffic in this corridor. In addition to user preferences the questionnaire focuses on the drawbacks in existing systems, user expectations for a new system. These were used to identify the user related issues in existing systems and to find whether a rapid transit can address those issues. According to the survey results, more than 50% respondents of indicated that BRT may be the better option for Colombo. Most of the passenger who travel daily for the work and low income (less than Rs: 50,000 per month) prefer BRT over others. According to the cost for install of new rapid transit system, MRT is more expensive than LRT system. Source of power can be use as Electrical power system because we have limited power supply for usage .Alternative other solution of energy we can think of renewable energy. BRT system need to more space than improving the current system and Monorail system is consume less space and required the mode of power to operate. The land value is going up day by day it will take considerable cost for land acquisition. According to the cost calculation for the selected road trace of Battarmulla -Fort, It is considerable cost reduction for the BRT system than the installation of Monorail system. It is required to establish criteria based on the cost /benefits, passenger’s preference, accessibility, connectivity with other modes, future expansion possibility, incentives for the land use development along with new system and emission levels of vehicles. According to the research, passenger preference for the BRT system, with the connectivity with other modes monorail systems is better than BRT. Possibility of future expansion of the system, there is a difficult with BRT system due to problem of Land acquisition. That can create significant social issues due to resettlement of people. From the environment point of view, more missions are expected from BRT system as compared to Monorail. Incentive for land use development along with BRT is restricted due to limited access to other vehicles considering all of the above monorail seems to have an edge over BRT.
item: Conference-Abstract
Development of a system for rating of hazardous locations along national highways
(Department of Civil Engineering, University of Moratuwa., 2014-08) Tharmini, K; Mampearachchi, WK; Bandara, JMSJ; Pasindu, HR
In highway safety plan; identification of hazardous locations on highways is one of the most important factors. In this study the geometric of road is considered to identify the hazardous locations with the concern of design standards of Road Development Authority, Sri Lanka. Availability of accident data is a significant requirement for identifying hazardous location of roads. However, for roads with poor accident data sets or no accident records, a method is needed to find and rank road segments with respect to road geometry independent of the accident records. In this study, initially hazardous locations or section of roads were identified based on Geometric Design Standards of Roads published by Road Development Authority on 1998. Then major parameters of road geometry such as horizontal alignment, vertical profile and road side activities and combination of these; are considered as main influence elements and identified the venerable factors of the each element. After that the relative contribution of the elements to the safety of critical location or road sections was determined by using the Analytical Hierarchy Process (AHP) with a system of scores which were suggested by an expert panel. Subject to a consistency test of the expert responses, AHP determines the weight of the elements. On which the horizontal radius is identified as most critical parameter of the geometry element, to induce accident prone hazardous location followed by long straight section or series of curves with small straight section with influence of the site condition.
item: Conference-Abstract
Framework for traffic incident management for Colombo Municipal area
(Department of Civil Engineering, University of Moratuwa., 2014-08) Srinivasan, J; Bandara, JMSJ; Pasindu, HR; Pasindu, HR
Various locations of Colombo City are frequently affected by traffic congestion daily. This may be due to insufficient road capacity during peak hours. But other times it is due to various incidents that occur here and there. An incident that occurs during peak hours worsens the congestion. Since congestion causes delays, wastage of human resources and fuel, increased rate of accidents, environmental pollution etc. improving the situation is utmost necessary. Even though the importance of minimizing the congestion has been realized by relevant authorities, they are reluctant to implement any plans considering possibility of high cost involvement. This study proposes a framework for managing traffic incidents with the available resources and existing institutional setup. CCTV Cameras and Variable Message Signs It is proposed to establish CCTV cameras at main junctions and Variable Message Signs just before and after the junctions along the main corridors, based on a criteria of selecting only main junctions, which provide another alternative route for the main corridor considered. As majority of the main junctions have already been equipped with CCTV cameras installed, only a few remaining junctions are to be fixed with cameras to cover the entire area. Vicinity of the city limits also taken into consideration for the incidents near to city limits. Message sign boards proposed to be fixed are having three different sections to show permanent direction markings, variable messages displayed and indicator lights. Variable messages and indicator lights are controlled by the Traffic Operations Centre. These indicator lights gives approximate traffic condition of the proposed alternative routes. Traffic Operations Centre The Traffic Operations Centre gets the messages, analyzes it and displayed suitably in the display panel. The centre is already in operation for monitoring activities, even though the cost of establishing is not there, necessary expansion of the centre will be required. Since it is necessary to display fairly accurate details in the signboard, well trained officers with sufficient traffic knowledge should be employed for this center. CCTV cameras will help to obtain real time updates. The Traffic Police who is currently involving with incident management, with the coordination of the Colombo Municipal Council and other stake holders and with a minimum improvements or modifications to their institution, could undertake this in an efficient way. Initial investment for Variable Message Signs, CCTV cameras and modifications to Traffic Operations Centre and for other improvements would be required but small when compare with the losses due to congestion. The system could be integrated with the agencies operating public car parks and an efficient parking management done. Parking also another main reason for the congestion. Gradually, private car park owners also could be entertained to display for the convenience for their customers. Funds for Maintenance Following Possible ways proposed 1. Fines imposed with the help of cameras. 2. Advertisements related to parking availability and other commercial activities.
item: Conference-Abstract
Identification of possible reasons that affect departure flight punctuality
(Department of Civil Engineering, University of Moratuwa., 2014-08) Sarojanie, SAN; Bandara, JMSJ; Pasindu, HR
A flight is said to be delayed when an airline flight takes off and/or lands later than its scheduled time. The Federal Aviation Administration (FAA) considers a flight to be delayed when it is 15 minutes later than its scheduled time. Punctuality is one of the key performance indicators in the airline industry and an important service differentiator especially for valuable high-yield customers. In addition, improved on-time performance can help achieve significant cost savings. This is a critical issue in the air transportation industry since it generates lot of problems to the operation and the inconvenience for the passengers. Once a delay is occurred, it is totally affect to the entire airline network and it will then effect to the passengers. Flight delays are an inconvenience to passengers. A delayed flight can be costly to passengers by making them late to their personal scheduled events. A passenger who is delayed on a multi-plane trip could miss a connecting flight. Anger and frustration can occur in delayed passengers. Hence airlines are always interested in making delays a minimum. This study focuses on identification of possible reasons for departure flight punctuality and a case study carried out on the National Carrier of Sri Lanka is presented. Attention was given to identification of departure flight delays, identifying critical delay types and finding their reasons based on Srilankan Airlines monthly delay reports. The findings of the analysis represents that there are 6% of Technical delays, 9% of Unavoidable delays, and 8% of Airport delays and 5% of Air Traffic Control delays out of average departure delays per day. The average delay time due to technical delays is 1.22hrs and average delay due to uncontrollable delays such as weather, late reporting of crew due to road traffic ant etc. is 0.34 hrs. Airport facility delays contribute on average 0.16hrs and average delay due to and of Air Traffic Control is 0.10 hrs per departure flight.
item: Conference-Abstract
Trends in heavy vehicle crashes in Sri Lanka
(Department of Civil Engineering, University of Moratuwa., 2014-08) Devasurendra, KW; Perera, L; Bandara, JMSJ; Pasindu, HR
Around 2,250 number of people die annually in Sri Lanka from road accidents. In 2013, the heavy vehicle percentage of the country is 8% but its involvement in fatal crashes is 21%. Therefore it is evident that heavy vehicles are playing a major role in fatal crashes. Finding the causes for these accidents and finding proper engineering and other solutions to minimize them have become of great importance. In order to find out the critical conditions and contributory factors for the severity of heavy vehicle crashes, a logistic regression analysis was carried out using accident details of heavy vehicles for the year 2013 extracted from Sri Lankan Police Accident Database. In the analysis, accident severity was considered as the dependent variable and crash factor for severity, vehicle ownership, validity of license, weather condition, road surface condition, location type, time of accident, urban\rural condition, light condition, road surface condition were considered as independent variables. Accidents occurrence at ‘Y’ junctions, SLTB bus involvement, drivers with probationary driving license, hitting a fixed object were found to be as having a significant effect on the severity of heavy vehicle crashes.

Browse

Browsing TRF - 2014 by Author "Bandara, JMSJ"