TRF - 2019

Permanent URI for this collectionhttp://192.248.9.226/handle/123/17956

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item: Conference-Abstract
Transport Research Forum 2019 (Pre Text)
(Department of Civil Engineering, 2019) Pasindu, HR
item: Conference-Abstract
Traffic conflict analysis for pedestrian crossings at un-signalized pedestrian crossings in Kandy
(Department of Civil Engineering, University of Moratuwa., 2019-09) Abeyrathne, MCC; Amarasingha, N; Pasindu, HR
Road traffic safety is normally measured in number of crashes and the consequences of the crashes in terms of severity. When the crash data are not available, the Traffic Conflict Technique (TCT) is used as an indirect method for determine the magnitude of the safety problem. TCT provides information on relative risks to diagnose the types of problems at a particular location, and it represents efficient tool to check location safety issues when there is limited or no crash data. The Lane Based Post Encroachment Time (LPET) will be the conflict analyzing method which used by many researches including Almodfer et al. (2016) followed to identify the pedestrian traffic safety in this study. LPET is the time difference between when the pedestrian leaves the conflict zone and at the same starting time when the vehicle approaches the conflict zone related to each lane. Pedestrian crossing area will be selected as the conflict zone in this method. For each pedestrian who uses the conflict zone, the time of he/she leaves the conflict zone and the time of the vehicle arrives the conflict zone is recorded. This study was conducted at two marked un-signalized crossings in Kandy; Katugasthota -Kandy road and Peradeniya-Kandy road. The pedestrian crossings which were selected to conduct the research were on four-lane roadways having flexible pavements with good condition. Data were gathered monitoring the videos recorded during the peak hours at the pedestrian crossings. For each pedestrian crossing 100 pedestrians were observed covering the approaching from both side of the crossing. The pedestrian crossing in Katugasthota-Kandy road had 50.5% of slight conflicts, 24.5% of serious conflicts and 25% potential conflicts for one direction. The other direction had 50.5% slight conflicts 33% of serious conflicts and 16% of potential conflicts. The crossing at Peradeniya-Kandy road had 40% of slight conflicts, 34% of serious conflicts, and 26% of potential conflicts for one direction. The other direction had 36% of slight conflicts, 39% of serious conflicts, and 25% of potential conflicts. The percentage of serious conflicts in Katugasthota-Kandy road crossing was high that may be due to the placement of a Filling station in front of the pedestrian crossing. Also, the existence of a bus stop near the pedestrian crossing in Peradeniya-Kandy road may be the reason for high percentage of serious conflicts in that crossing.
item: Conference-Abstract
The physical components of noise and vibration of rail transit and its effects including control measures
(Department of Civil Engineering, University of Moratuwa., 2019-09) Narayanan, L; Pasindu, HR
Noise pollution generated by transport is acknowledged to be a major environmental problem. The use of environmental noise barriers, already widespread in Europe and the USA is now becoming increasingly important, changing the face of our road and railway networks and this in large urban areas is regarded as a growing problem of communities and there are various factors that contribute to increase of noise levels in urban areas. One of the factors is the increase in urban population, which contributes to high traffic volume combined with increased intensity. In most urban areas, the corridors are developed in a proximity where people live and work, which led to limited space and thus increase the number of high-rise buildings. This type of settlement created a dense environment in urban areas, thus increasing the traffic volume. Numerous countries have implemented new technologies to control noise pollution in urban areas. For example, low noise generating engines, changes in quality of vehicle tires and changes in road material and these technologies have proven to reduce the noise on individual scale and as the overall noise pollution in urban areas is still increasing because of increasing traffic volume. It is of great importance that noise modelling software on multiple noise scenarios and must be able quickly and reliably to turn these models into noise maps and these maps are used to assess and monitor the influence of the noise effects as well noise maps can be helpful in planning and decision-making processes for reducing the noise pollution. With the speedy development of urban mass transit system, more and more environmental concerns are focused on the vibrations from underground trains. Vibrations can arise from the passage of trains inside the tunnel and spread through the tunnel and surrounding soil into nearby buildings. Ground-borne vibration can be a serious concern for nearby neighbors of a transit system route or maintenance facility, causing buildings to shake and rumbling sounds to be heard. In contrast to airborne noise, ground-borne vibration is not a common environmental problem. It is unusual for vibration from sources such as buses and trucks to be perceptible, even in locations close to major roads. Some common sources of ground-borne vibration (other than train) are buses on rough roads and construction activities such as blasting, pile-driving and operating heavy earth-moving equipment. Vibrations in buildings associated with rail network operations can cause disturbance and complaint in a similar manner to noise. It needs to be considered at the infrastructure planning stage as is difficult to mitigate retrospectively.
item: Conference-Abstract
A quantitative review on travel-time reliability measures
(Department of Civil Engineering, University of Moratuwa., 2019-09) Vidanapathirana, CJ; Bandara, JMSJ; Pasindu, HR
The time spent on a trip which is termed the ‘travel time’ is a key parameter in effective journey planning. Having an understating about the travel time for a specific journey is crucial when deciding upon the departure time and route choice. With the advancement of technology, services and products have been introduced which provide travel time data and estimations to fulfil the journey planning needs. These are popularly being used by most of the travellers worldwide since the traffic conditions have become fairly unpredictable in the past few decades. A common concern the travellers have today is the accuracy of the estimated travel times. Since the estimations are based on historical data and real-time data, an accuracy of 100% can’t be achieved. Further, travel time depends on parameters which create uncertainty such as traffic composition, junction delays, pavement conditions, roadside accidents, special events (e.g.: a protest march) and weather. Some of these parameters can neither be quantified nor be predicted. Studying the reliability of travel time became a major focus area in the field of transportation engineering with these recent developments. Various studies have been conducted in the interest of developing travel time reliability measures. Most commonly used travel time reliability measures are 95th percentile travel time, buffer index, planning time index and travel time budget. It is important to mention that such measures need to be simple and easily understood by people who aren’t thorough with technical knowledge. If not, the public will not be able to incorporate travel time reliability for journey planning purposes. This study is a review on the usability of travel time reliability measures. What is expressed by each measure, how they can be interpreted and how helpful they are for the users are discussed through this analysis. A large data set of travel times was used to develop reliability measures for a selected set of road links. Verification of the results was done afterwards. Mainly this can be described as a quantitative review with a qualitative analysis on the final outcomes.
item: Conference-Abstract
Analysis of the level of safety of public transport in a ‘sustainable development goals’ perspective in the national context
(Department of Civil Engineering, University of Moratuwa, 2019-09) Thilakshan, T; Bandara, JMSJ; Pasindu, HR
In 2015, Sri Lanka along with 192 member countries of the United Nations identified the timeliness of the concept of ‘Sustainable Development Goals’ (hereforth referred to as SDGs) and mutually expressed their desire to work individually and collectively to achieve the SDGs by 2030 post the Millennium Development Goals tenure from 2000 to 2015. It can be observed that the diverse nature of the context of the goals and their targets is a cross cutting concern dissecting many sectors and concerns listed by the 17 goals and 169 targets. Sustainable Transportation in the context of the United Nations has been classified into five dimensions: Accessibility, Affordability, Safety, Security and Environmental concerns. In this context, Public Transport plays a significant role in the sustainable transportation spectrum. Public Transport Safety is analyzed in this study in a global and national perspective in the context of the overall safety in transportation. The study narrows down to the concept of Public Transport safety which is identified as the one of the largest negative concerns in the current arena with a large number of commuters using the same mode at a given point of time involving high human intervention. Two targets listed in the SDGs give direct leverage to Road safety which also apply in the case of Public Transport: SDG target 3.6 - Halve the number of road traffic deaths and injuries by 2020 and SDG target 11.2 - Provide access to safe, affordable, accessible and sustainable transport systems for all by 2030. The Global Sustainable Transport Conference which was held on the 27th and 28th of November 2016 in Ashgabat, Turkmenistan highlighted the importance of sustainable transport in promoting economic and social development while protecting the environment and the main concern was the large number of annual deaths from road traffic accidents along with the environmental impacts of transportation. In both regards, Public Transport plays an important role and the safety assurance of Public Transport is one of the main dominating factors in attracting people to Public Transport modes, which mainly constitutes buses and trains in the national context. Thus, the study identifies the importance of Public Transport safety to achieve sustainable transportation and SDGs while analyzing the current status of Public Transport using available data and statistics in a national perspective. Apart from studying the pattern of Public Transport in terms of deaths, injuries and related parameters, more concern in the study focusses on the post 2015 SDG timeframe to evaluate the impact of the SDG framework in the context of road safety and the practicality of achieving the SDGs: target 3.6 by 2020 and target 11.2 by 2030 in the perspective of Public Transport. 90 percent of road traffic deaths occur in low and middle-income countries even though the countries count to only 54 percent of the world’s vehicles percentage. Sri Lanka is no different in terms of the crucial impact of road safety and analyzed data from the National road safety council of the Ministry of Transport and the Sri Lanka Police show no decrement in terms of road safety accidents and resulting deaths, injuries and damages. The analysis looks into the impact of Public Transport to the overall safety scenario and the steps that needs to be taken in dealing with Public Transport based safety issues with utmost importance due to the large number of lives involved in the scenario and the attraction factor of people towards using Public Transport as an alternative for their private vehicles. The number of private passenger transport buses and Sri Lanka Transport Board (SLTB) involved in the accidents and their rate of involvement in an annual and monthly timeframe is analyzed along with the accident type. Thus, an analysis on public transport buses is carried out in an individual and overall (Private and SLTB buses) manner for better understanding. An analysis framework of the Railway sector and accidents in a periodic timeframe along with the category of railway accidents involving the railways is included in the study. Thus, the study analyzes the overall Public Transport in the national context with respect to safety and the reasons involved in the accidents along with evaluating the current position of the transport sector in terms of sustainable transportation in terms of public transport and achieving the SDGs in the national context.
item: Conference-Abstract
Development of methodology to estimate trip attraction and parking demand for urban office developments: case study- Colombo
(Department of Civil Engineering, University of Moratuwa., 2019-09) Priyadarshani, M; Pasindu, HR; Pasindu, HR
Urban commercial developments are an integral part of the urban land use and this affects the trip generation and attraction pattern in the city. More importantly these developments increase the demand for parking, which by law should be provided within the development. Lack of adequate parking facilities will impact the road network as it will lead to on-street parking and additional vehicular circulation to and from public car parking areas. Furthermore, provision of parking within the premises results in an increase in the cost to the developer which can escalate the prices of the property. Moreover, due to lack of local norms to indicate accurate traffic generation factors for different types of developments such as office complexes, business establishments etc., it is hard to forecast accurate future traffic figures that will generate due to the proposed new developments. Therefore, regulations need to ensure adequate number of parking are stipulated based on the type of facility. Parking regulations for office building type developments used for the city of Colombo is based on gross floor area of the building, which may not necessarily represent the parking needs of the building depending on the type of operation which takes place. Therefore, the existing parking regulations for these types of development need to be revised in order to assess the optimal parking requirement for different types of office buildings. The study develops a methodology to estimate trip attraction patterns and parking demand for urban office developments. For that research aims to evaluate the trip attraction patterns for different types of office developments and it investigates the effectiveness of current parking regulations and calculation methods in Sri Lanka. Similarly, it identifies new criteria to evaluate parking provisions for the new office developments. Finally based on study results parking demand and trip attraction rate will be assessed.
item: Conference-Abstract
Effect of styrene – butadiene – styrene (Sbs) on mixing process and laying of asphalt concrete
(Department of Civil Engineering, University of Moratuwa., 2019-09) Varshihan, V; Mampearachchi, WK; Pasindu, HR
Construction of flexible pavements involve the production and utilization of asphalt concrete (AC) for the wearing course and the binder course. The sustainable production of AC mixtures has become a major concern internationally. Recycling of waste polymer materials can be identified as an effective method which improves the aspects of sustainability and economy of highway construction projects. This research was conducted to investigate the modification of asphalt properties using Styrene-Butadiene-Styrene (SBS) as a modifier and to check the performance of the modified asphalt mixtures in the aspects of the quality and the cost at plant scale production. At the initial phase, the selected bitumen binder was mixed with the SBS modifier to produce an AC mixture in which SBS acts as a binder modifier for bitumen, and as a filler modifier for aggregates. Mix design details for AC were obtained from the Marshall mix design. The first set of production was done for 6% of SBS to the total bitumen weight. SBS was added quickly to the pre-blending bitumen tank while stirring at 180 oC -190 oC temperature during the wet process. Then the mixture was allowed to flow through the high shear mixing and dissolving tank to produce a uniform mixture. Subsequently, the modified bitumen was mixed with the aggregates at a mixing temperature of 170 oC – 180 oC. Then the mixture was placed before it reaches the recommended laying temperature of 140 oC. The optimum compacting temperature was obtained by changing the temperature of the mixture. The asphalt mixture was heated at the respective temperature and it was kept for 10 minutes at boiling water temperature to find the mixing temperature for a better coating of the modified bitumen. At the final phase, the physical properties of asphalt mixtures were investigated using Marshall test parameters including the stability value, the flow value, the percentage of air voids, and the percentage of voids in mineral aggregates (VMA). Wheel tracking test was also conducted. Cost analysis of the above production process was investigated by varying the parameters of the plant operation such as the mixing time, the control temperature, and the set of plant modifications. Considering the outcomes of this research, it is recommended to improve the efficiency of the plant operation processes for the modification of AC. This will also enhance the sustainability by minimizing the hazards to the environment due to the waste polymer materials causing environmental pollution.
item: Conference-Abstract
Sub base improvements by stabilization techniques using waste materials
(Department of Civil Engineering, University of Moratuwa., 2019-09) Sathiyaparathan, T; Pasindu, HR; Pasindu, HR
Improvements of rural roads are vital socio-economic pathways to a better quality of life for most of the Srilankan people living in rural areas. The fund allocated for low volume road project is limited, thus it is important to use existing resources for economic advantages. Also, adverse environmental impact can be reduced. Roads are designed for low-volume traffic and are constructed of local soils containing high percentages of fines and high indices of plasticity. These soils may not have characteristics appropriate for the sub base in the construction of flexible pavement in rural roads. Thus, it is necessary to modify or stabilize this kind of soil to make it suitable for construction. The soil modification process can be effectively used to meet the challenges of sustainability of the environment, to minimize the adverse effect of industrial wastes such as plastic, glass, paddy husks, etc. Wastes are increasing day by day leading to various environmental concerns. Therefore, the disposal of those wastes without causing any ecological hazards has become a real challenge. Thus using plastic waste, glass waste & paddy husks as stabilizing agents is an economical utilization since there are demand and shortage of good quality soil for sub-base. This research involves a detailed study on the possible use of the waste products for soil stabilization for the sub-base material in the North Central Province I-Road Project in Sri Lanka. A series of field and laboratory tests were carried out for collected sub-base materials to identify the deficiency of sub-base material properties. ICTAD specification for the roads was referred and confirmed to the specification for the road projects in Sri Lanka. The specification says that Liquid Limit should be less than 40 (LL<40) and Plasticity Index should be lesser than 15 (PI<15). Sub-base materials from Polonnaruwa area were stabilized with different percentage of paddy husk ash, plastic waste and glass waste with weight-based mix proportions. But the experimental study demonstrated that with an 8 % mix of paddy husk ash as a reduction in Liquid Limit by 20 % and Plastic Index by 26 % was achieved. Also, California Bearing Ratio of the stabilized sample was improved by 10% as well. Finally, it was concluded that the stabilized composite soil can be used for the construction of flexible pavement in rural areas with low volume traffic.
item: Conference-Abstract
Thin lift asphalt concrete pavements for low volume roads
(Department of Civil Engineering, University of Moratuwa., 2019-09) Udayakantha, PMAK; Mampearachchi, WK; Pasindu, HR
Sri Lankan road construction sector is dealing with ever depleting construction material problem specially finding good quality aggregate has become more and more difficult for projects over the past few years. The accelerated development demands lot of natural resources and the extraction of resources like aggregate in mass scale also pose a great threat to the environment. Using the available resources sparingly and optimally is the way forward to brace the scarcity of construction material we are about to face. There are many projects in progress to upgrade low volume roads. But the designs are done using 50mm asphalt wearing course which is a very conservative approach given the traffic movements of the roads are very much low. For the traffic levels in such roads by using a thin asphalt layer which is between 25mm-35mm the same design life could be achieved while cutting down costs significantly. The aim is to adopt a mix which can be laid in thin layers and perform well in Sri Lankan conditions. To determine the characteristics and performances of thin layers first a suitable 10mm aggregate mix should be selected, for that mixes in section 404 of VicRoads August 2018 were selected and SMA10N mix was selected from the available mixes due to replicatability of the mix using available plant hot bins. Then Marshals were casted using the average line of the aggregate gradation and mixing with 60-70 penetration grade bitumen and tested for their properties. It was evident that though all other properties were satisfied except the VMA values, the specification requires addition of cellulose fibres to the mix but literature and availability prompt the use of glass fibers which exhibits superior properties. Addition of glass fibers 0.1%-0.2% can increase the air voids and VMA values while retaining the other parameters in specification range. The glass fibers can be used to manipulate mix properties in order to get desired properties and a satisfactory mix. The addition of fibers may also increase fatigue life and it should be checked using indirect tensile test.
item: Conference-Abstract
Evaluation of rheological properties and performance of asphalt binder modified with nano clay
(Department of Civil Engineering, University of Moratuwa., 2019-09) Shantha, YGPB; Mampearachchi, WK; Adikary, SU; Pasindu, HR
The rheological behavior of bitumen is very complex and it can be varied from purely viscous to elastic depending on the loading time and the temperature. Bitumen plays a major role in many aspects of road performance. Various investigations have been carried out related to the modified bitumen to improve the performance of bituminous mixtures. Most of the Roads are failed due to the rutting and cracking of the bituminous layer which is due to the mostly poor performance of bituminous binders. So, the modification of the bitumen has been major approach in today and modified bitumen is effectively used in many countries during last three decades to construct the pavements. This research presents a laboratory scale evaluation of the conventional and the fundamental rheological characteristics of modified binders with micro clay and Nano clay contain 2%, 4%,6% & 8% by its weights. Engineering fields are widely used montmorillonite (MMT) nano clay for wide range of applications. In Sri Lanka also, there had been few researches about the usability and characterization of MMT clay which is available at Mannar area near to the Giant tank. The clay powder prepared from the original samples taken from the above area was added to the original bitumen of 60/70 penetration grade binder to prepare the modified binder. The prepared clay powder was subjected to the X- ray diffraction to identify the MMT clay. Modified bitumen samples were prepared by adding nano clay mixed at 1600C with the mixing time of 25minutes. The properties of the modified binders with nano clay were evaluated in terms of their properties using penetration, softening temperature, ductility and dynamic viscosity tests. Finally, modified bitumen each sample were evaluated for the rutting and fatigue resistant for fresh and aged samples with the Dynamic Shear Rheometer (DSR) test. It was observed by the results obtained from the tests that the softening point and viscosity increased up to 4% clay, penetration and ductility has decreased with increasing of clay percentage. Rutting resistance has not improved with compared to conventional bitumen and it was showed that modified bitumen and original sample were showed PG 70 grade with 2%, 4%, 6% and original bitumen sample. Finally, few samples of modified binder with nano clay was checked with Furrier Transform Infrared Spectrometer (FTIR) to identify any chemical changes with compared to conventional bitumen. As a conclusion from these findings that is the montmorillonite clay modification helped to improve some characteristics of the bitumen binders. But at this level they are not at the stage to verify application at large scale.
item: Conference-Abstract
Feasibility study of using industrial waste as an internal curing aggregate for rigid pavements
(Department of Civil Engineering, University of Moratuwa., 2019-09) Pradeep, KI; Tharshigan, T; Mampearachchi, WK; Pasindu, HR
The hydration process of cement in concrete affects the temperature conditions and moisture content which indirectly cause for strength, shrinkage and cracks. Curing starts immediately after setting of concrete. American Concrete Institute describes curing as “action taken to maintain moisture and temperature conditions in a freshly placed cementitious mixture to allow hydraulic-cement hydration and, if applicable, pozzolanic reactions to occur so that the potential properties of the mixture may develop”. In external curing of rigid pavements, water inside the concrete consumed for hydration of cement, some part of water escapes to the atmosphere through concrete surface and some part absorbs to the ground. Thus. Internal drying occurs which reduces the relative humidity while increasing the internal stresses which results in shrinkage and thermal cracks. External supplied water will only affect for top part of the concrete layer. Internal curing method has been introduced as a solution to the problems encountered in external curing. According to American Concrete Institute, they defined internal curing as “a process by which the hydration of cement continues because of the availability of internal water that is not part of the mixing water”. It’s a method which supply water internally through water reservoirs which need for hydration process. This research is to develop a fine aggregate for rigid pavements which performs the internal curing properties using industrial waste. Water treatment sludge (WTS) and Textile Effluent sludge (TES) used as industrial waste to prepare fine aggregates. After several steps in treatment process to remove inorganic, organic contaminants and suspended solid particles in surface water, produce large quantities of sludge by removing impurities from raw water. Sludge removed from above process called ‘water treatment sludge’. Textile industry consume large amount water to convert raw materials and fabric to finished clothing materials. Specially for dyeing. So large quantity of sludge produces in the waste water treatment plants due to this case. The disposal of sludge from water treatment plants and textile dyeing industry is a huge issue for related authorities. Introduce a value-added product for waste sludge will be another solution for the waste. The water treatment sludge and textile effluent sludge was dried under sunlight and crushed in to powder form which passing through 0.6mm sieve. Thermogravimetric analysis and Differential scanning calorimetry are conducted to identify the thermal behaviour of sludges. Different mixtures were prepared by changing two sludge contents (100% WTS, 90% WTS+10%TES, 80%WPS+20%TES). Atterberg limits was initially identified to select the optimum water content need to mix the samples. For laboratory tests, cylindrical samples (Height; 80mm, Diameter; 17mm) were prepared for heating process. Slow heating method used to sinter the samples for different temperature levels (8000C, 9000C, 10000C, 11000C, 12000C). Then samples were crushed to small particles which passes through 4.75mm sieve and retained on 0.6mm sieve. Water absorption test, Relative density test, bulk density test was conducted to observe the physical properties of developed fine aggregates. Scanning Electron Micrographs (SEM) analysis was followed to observe the microstructure of the fine aggregates. Compressive strength test was followed to identify which temperature shows the higher strength of fine aggregates. According to ASTM C1761M, internal curing aggregate shall have a 72-h absorption not less than 5%. Also, the fine aggregate shall release at least 85% of its absorbed water at 94% relative humidity. When Kelvin equation combined with Young’s equation, a relationship between relative humidity and size of the pores being is established. According to the relationship, the pore size should be more than 200nm to release water from aggregate. The fine aggregates which developed using sludge waste shows higher water absorption which need for internal curing property. According to the SEM analysis, it shows that the pore size increases with the temperature and textile effluent sludge content. According to thermogravimetric analysis, compressive strength test and microstructure, it concludes that 1150oC is the optimum temperature to heat the sludge waste. The optimum textile effluent sludge and water treatment sludge were selected as 20% and 80% respectively, while 45% of water content should be added when preparing the mixture. As a conclusion to the above findings, the fine aggregates which developed using sludge waste feasible to use as an internal curing aggregate in rigid pavements.
item: Conference-Abstract
Logit choice model for boat passenger transportation in Colombo, Sri Lanka
(Department of Civil Engineering, University of Moratuwa., 2019-09) Kaushalya, SMD; De Silva, GLDI; Pasindu, HR
Public transportation service in Colombo canal network is a viable alternative or addition to road and rail road on Colombo Metropolitan Region (CMR) corridors. Though environmentally friendly and frequently, the most economical mode of canal boat service, it remains largely under exploited in Sri Lanka. The prevailing public transportation modes such as bus, train and private transportation modes such as cars, motor bikes and taxis play vital roles in passenger movements within the country. But with the increasing population and the land scarcity in CMC region vast traffic and congestion problems exists in prevailing conditions. Thus, introducing another transportation mode is essential for future. Lack of data availability in the transport mode choice modelling has create problems implementing passenger boat transportation in CMR that leads to do more researches in the field. This study intends to present an idea of developing suitable passenger choice model on the basis of discrete choice modelling technique. ALOGIT software has been used for model setup and data analysis process. A stated preference pilot survey has been carried out in CMR region by proposing a public boat service route from Wellawatta to Battaramulla. The model was done for single level logit model. ALOGIT model was estimated to develop utility function to get an idea about people’s behavior patterns based on their socio-economic characteristics like age, gender, income level and based on travel characteristics like journey time, journey cost, waiting time, transit time. Further, separate travel characteristics, boat journey time and boat journey cost has been introduced to the model setup to identify public opinion of suitable fare terms for public boat transport service along the Colombo canal network. Results of this study provides an insight to incorporate boat transport service within the mainstream of CMR transportation planning.
item: Conference-Abstract
The evaluation of factors influencing cycle trips in a heritage city. a case study on cycling tourist in Anuradhapura sacred city
(Department of Civil Engineering, University of Moratuwa., 2019-09) Wanniarachchi, SS; De Silva, GLDI; Pasindu, HR
As the world endures an energy dilemma, most developing communities advance toward energy efficient modes and non-motorised transport modes such as walking, roller skate, skateboard and cycling. Cycling is an environmentally friendly mode that enables the commuter to experience the surroundings. Other than commuting, cycling-tourism is about a long to medium distance cycling trip for pleasure, experience, and liberty rather than exercise or sports. Being one of the major tourist attraction zones in Asian region, Sri Lanka experiences over two million tourists’ arrivals every year to visit South and East Coast, Ancient Cities, Hill Country and Northern Region. Anuradhapura is one of the well-known ancient cities with many historical monuments connected with roadway links. This study identifies the design and influencing factors of local and foreign tourists to encourage cycling within the Anuradhapura ancient sacred city rather than using 3-wheeler taxi or other motorised travel methods. As phase 1 of the research, an initial survey was carried out inside the Anuradhapura sacred city with a sample of twenty-one respondents out of the target population of local and foreign tourists. Data has collected through a questionnaire survey and discussions. The factorial extraction has been run to determine the factors influencing cycling tourism, and descriptive statistics have used to present the socio-demographical features of the study sample. The secondary aim of the research is to review the variations in soft mobility choices by local and foreign tourists based on the design and the extracted manipulating factors. The analysis of data has generated factors with very strong loadings to represent the variables used in the survey. The descriptive analysis shows that the majority of the tourist visit Anuradhapura for pleasure, religious and business. Most of the tourist respondents had arrived from East Asia and Europe. The study explains that majority of them has used motorised transport to arrive at Anuradhapura and after arriving has used cycling within the sacred city. The analysis has highlighted that greater number of tourists prefer to use cycling for a short distance journey. The respondents have commented that safety and security issues have been a major tragedy in riding cycles inside the sacred city. It had mentioned that potholes in the road and the areas where the road has been damaged and unpaved had caused notable accidents to the cycling tourists. The risk of theft and the awful surroundings in some areas of the sacred city has discouraged cyclists from riding through the area. The further discussions with cycling renters and cyclists have highlighted that the cycling tourist, both local and foreign have been relying on verbal instructions of landmarks and road, as the Anuradhapura tourist city map provided by the Ministry of Tourism - North Central Province and the google maps has not been providing the accurate information on the routes and pathways inside the sacred city. The effort of the research is to help town planners prioritise services and improvements designated to the location to promote cycling tourism. Sri Lanka’s tourism is one of the revenue generations industries through cycling tourism in the early stages of development. This study has taken a general view concerning the influencing factors of Anuradhapura scared city cycling tourism to develop the cycling within the sacred city and to develop the soft mobility within the Anuradhapura district ensuring more eco-friendly urban surrounding.
item: Conference-Abstract
A review on demand responsive transportation system
(Department of Civil Engineering, University of Moratuwa., 2019-09) Randeniya, RDSS; Perera, WULDP; Anburuvel, A; Pasindu, HR
Public transport services are generally of a reasonable standard on the main corridors of many countries, they tend to be inadequate; to meet users’ needs in rural and other low population density areas, for servicing during off-peak times and to operate specialist community-based services for elderly population and differently-abled population. As the next level of transport services, the para-transits are not capable of managing high demands and not affordable for a considerable number of passengers because of the high cost. Providing regular transport services to all regions of sparse population is not economically feasible. These reasons have paved the way for the implementation of Demand Responsive Transport (DRT) all over the world. DRT is a class of flexible transport services in which a fleet of vehicles dynamically changes routes and schedules, in order to fulfill the individual passengers’ requests through door-to-door rides by specifying their desired start and end locations. Manifestations of Special Transport Services (STS) have provided dedicated solutions for special groups in parallel to the conventional public transport network. But to meet the growing demand more effectively and efficiently with low cost, DRT has evolved towards developing a niche for the general public. (Nelson, Wright, Masson, Ambrosino, & Naniopoulos, 2010). Further DRT evolved for feeding the conventional public transport network to provide wider access and opportunities. [e. g. Bus Rapid Transit (Lindau, Hidalgo, & Lobo, 2014)]. The Melbourne Telebus which has been operating in this concept for over 30 years is a hybrid falling somewhere between a full dial-a-ride service and fixed-route bus service. (Scott, 2010). With the support of advancements in vehicle tracking, communication and computing, automated demand responsive transport systems (Winter, Cats, Correia, & Arem, 2016) have been implemented recently. Sri Lanka has a public transport system supported by para-transit services which are plenty in big cities and towns (e.g. Colombo, Galle, and Kandy). However, the sparsely populated areas (e.g. Kilinochchi, Moneragala) have insufficient, inaccessible public transport and a limited number of high-cost para-transit services. Approximately 80% of the population in Sri Lanka is in sparsely populated areas. (Lanka, 2012). And also with the rapid increase in elderly population, the portion of differently-abled population in Sri Lanka [87 per 1000 persons (Disability in Sri Lanka - the United Nations, 2012)], as well as the increase in dispersed land-use patterns emphasize the necessity of door-to-door effective transport. A more effective and advanced DRT system is an immediate need for Sri Lanka covering a wide spectrum. By adopting the best practices of successful services DRT can have a role to play within the transport sector in sparsely populated areas in Sri Lanka.
item: Conference-Abstract
Development of bus service reliability measures at the stop level
(Department of Civil Engineering, University of Moratuwa, 2019-09) Sharic, AHS; Bandara, JMSJ; Pasindu, HR
Bus service reliability, one of the key performance measures, has become a major concern of both transit operators and users because it significantly affects user experience and service quality perceptions. Schedule adherence has been the most important existing reliability measure for infrequent services that operate with headways of more than 10 minutes. For routes characterized by high frequency service namely less than 10 minutes of headways, headway variability has been the most important existing reliability measure. But these measures do not differentiate between the cost of being early versus late. Different unreliability characteristics that cannot be captured by the existing measures calls for a supplementary measure. This research adopts two indices from (Saberi, et al., 2013) that overcome those issues such as Earliness Index (EI) and Width Index (WI). The Earliness Index is defined as the percentile rank of delay/headway deviation of zero. The percentile rank of a particular delay/headway deviation is the percentage of delay/headway deviations in its frequency distribution that are lower or equal to it. EI ranges between 0 and 1. For frequent services, an EI of 0 represents the “all behind schedule” condition and an EI of 1 represents the “all ahead of schedule” condition. For not frequent services, an EI of 0 represents the “all late” condition and an EI of 1 represents the “all early” condition. For infrequent services, the theoretical ideal distribution lays on the y-axis of the cumulative distribution function. Buses that are early can be treated as being one headway late, because passengers who are arriving near the scheduled departure time would have to wait for the next bus. Therefore, the “all late” condition is expected to be the achievable ideal distribution for non-frequent services to avoid early departures. Note that the above statement is true only when the theoretical ideal distribution (all “on-time” condition) is not achievable. The closer the EI is to 0, the more reliable is the service. For frequent services, one cannot argue similarly, since maintaining a fixed headway with a small deviation is more important than being ahead of or behind the schedule. Thus, another measure is required to capture the variation of headways. To capture the width of the distribution of headway deviations in frequent services, the Width Index (WI) is defined as the 95th percentile of headway deviations minus the 5th percentile of headway deviations divided by the average scheduled headway. .Data needed for theses are as follows. Using the existing time keeper records at the bus stops, a number of measures can be simply calculated. The scheduled headway at a particular stop can be computed as the scheduled stop time for trip i at a stop minus the scheduled stop time for trip i-1 at the same stop: Note that the proposed reliability indices are not suggested as replacements for the existing measures; rather, they are complementary.
item: Conference-Abstract
A GIS based methodology to redistribute macro-level origin destination data based on the land use
(Department of Civil Engineering, University of Moratuwa., 2019-09) Weerasinghe, O; Bandara, JMSJ; Pasindu, HR
The Origin-Destination (OD) data are often collected for the transport infrastructure planning projects to study the travel patterns. Conducting OD surveys are expensive and time consuming. Therefore, the practitioners tend to collect OD data according to a macro level zoning system. In Sri Lankan context; OD surveys are conducted based on Divisional Secretariat Division (DSD) boundaries. Further, OD surveys within major towns, such as Colombo, Kandy were conducted, considering the smallest administrative boundaries in Sri Lanka; the Grama Niladhari Division (GND). Since the trip production and attraction is related to the landuse pattern of an area, the landuse can be considered as an independent variable in estimating the trip generation. Two models were developed to demonstrate the relationship between landuse (landuse floor area in m2) and the trip generation as follows; Trip production = 9117.980 + 1.425 (Private offices) + 0.792 (Educational) + 0.174 (Commercial) + 0.466 (Tourism) + 0.007 (Residential) ------(1) Trip attraction = 6914.287 + 0.201 (Commercial) + 0.730 (Educational) + 0.189 (Health) + 0.010 (Residential) + 0.551 (Tourism) ------(2) The research leads to redistribute the macro-level OD data into a modified zoning system based on its landuse character; specifically, DSD level OD data are redistributed among more than 100 zones. The research is based on both spatial and statistical analysis and spatial software, such as ArcMap, QGIS and statistical software, such as SPSS and MS Excel were utilized. The Colombo DSD was considered as the study area and subdivided into 179 modified zones. The number of trips attracted to Colombo DSD from other 330 DSDs was divided proportionately to the trip attraction factor of the modified zones. Likewise, also the trip production was calculated. There were 59,070 OD pairs between 330 DSDs and 179 modified zones. The passenger trip assignment was done assuming that all the passengers travel via the shortest route between origin and destination.
item: Conference-Abstract
Barriers in modal integration: the case of rail and bus transportation in Sri Lanka
(Department of Civil Engineering, University of Moratuwa., 2019-09) Bandara, YM; Rathnayake, T; Pasindu, HR
For the existence of competitive markets, transportation is an essential economic activity needed to fulfill the activities of daily needs by providing a mode for the mobility of people and freight. A selection of specific planning method of transportation, convincing the passenger to use public transportation over private transport modes is a vital element in the current transport policies. Efficient operation of transport services depends on how effectively transport planning is undertaken considering technical, economic, market, social and environmental requirements under which services are provided. Nowadays every country in the world is trying to establish its own national transport system, not in isolation but as a part of the international system of transportation. When a transport mode is incorporated into a model, it can be used to build a better transportation system by using split development, model share and model integration. However, the passenger flow would not take place as predicted by transport models due to the influence of personal transport modes. As a result, developed infrastructure and transport services are often underutilized or one attractive mode of transport services are highly demanded to lead to overcrowding. This leads to the development of modal share issue with public transport share tends to decline while private motorized transport share is on the rise. As a remedy, model integration is considered as one seamless entity which has made by the involving of the travel modes for the benefit of the fare paying customer. There are many integrated transportation systems can be seen in well-developed cities all around the world established to reduce car dependency (Buehler, Pucher, Gerike & Götschi, 2017). Transport modal integration (Intermodality) provide the advantages by keeping space through the traffic congestion and controlling and resultant time saving and vehicle operational costs savings to users, minimizing carbon footprint and other negative externalities and eventually reducing the country dependence on fuel. However, intermodality is not always successful due to certain barriers. This paper aims at identifying the barriers that affect to efficient model integration process between bus and railway service around selected bus and rail corridor. The methodology followed in this research is a questionnaire-based data analysis using Principle Component Analysis (PCA). The relevant data were collected through a field study conducted in a selected public transport corridor that is served by rail and bus transport. The data collection was carried out using an online survey form but carried out as face to face. At all location 100 randomly selected passengers were surveyed. Data from each location were collected to cover all the time frames as possible and covering different users of the transportation service. Main factors acting as barriers to modal integration were derived as operational factors, comfortability, infrastructure design, competition, information flow and ethical behavior from the PCA analysis. Fourteen barriers identified, which includes security and safety concern of train, lack of information of bus and railway operating times, the capacity of current bus and train service and operating conditions of bus and railway stations, have been perceived as the main issues to be solved that make passengers participate in model integration between bus and railway services. Further, poor sanitary facilities, having uncomfortable fare collection methods and health and fitness issues of passengers have also been barriers. Further, considering the travel complexity of passengers in the sample, 28 travel patterns have been identified which includes traveling modes of the bus, foot, train, three-wheelers, taxi cabs and personal vehicles such as cars, bikes, and vans. Most of those 28 patterns have similar areas of destinations even they have different origins indicating hub and spoke transport behavioral pattern. Variable origins, less planned travel facilities, not having proper integration method, have been main reasons for the travel complexity.
item: Conference-Abstract
Formulation of a national framework for the digital transformation of Sri Lanka’s public bus transport system
(Department of Civil Engineering, University of Moratuwa., 2019-09) Dunuwila, VR; Jayakody, JADCA; Lokuliyana, S; Pasindu, HR
Public transport is considered to be a country’s primary transportation network that plays an increasingly important role in human navigation. Thus, many countries have digitally transformed their public transport services to ensure the delivery of a quality transportation experience to passengers whereas the use of digital practices in Sri Lanka’s bus transportation industry is minimal. As a matter of fact, majority of the vehicles entering Colombo are private vehicles that carry an immaterial number of passengers compared to public transport. The availability of more private vehicles with less number of people gives rise to the problem of traffic congestion thus creating a requirement for an efficient public transport system. Hence, the authors aim to present how modern-day IT advancements could be used to deliver a quality bus transportation experience to Sri Lankan passengers. First, the challenges experienced by passengers were investigated where, heavy traffic, long travel time, overcrowded buses, not receiving the correct amount of balance money and the inability to track the location of the bus beforehand were found to be the most common challenges experienced by passengers. Once, the issues and the corresponding needs were identified, the authors explored the different roles of IT in public bus transport and proposed four feasible solutions to overcome the prevalent issues. The recommended solutions consisted of a bus tracking cum arrival time prediction system that uses GPS and GSM, a bus crowd monitoring system that uses IR sensors, a cashless ticketing mechanism that uses the Touch travel card introduced by Dialog and an inquiry cum complaint management system that would facilitate real time complaint handling and management. Furthermore, the research also introduced a digital transformation framework that could be used to digitalize the operations of public bus transport. The digital transformation of Sri Lanka’s public bus transport system would result in the delivery of a quality transportation experience to passengers while minimizing traffic congestion in Colombo as the availability of a high-quality bus transport service would encourage citizens to use public transport more often instead of their own private vehicles. The proposed research contrasts with other researches as it facilitates the development of a Digitized National framework that would be applicable to the entire bus transport system of the country. Furthermore, it would be beneficial if the passengers are provided with an integrated up-to-date solution where information such as the location of the bus, arrival time, bus fare, duration and journey distance is available in real-time. Besides, the study is also significant as this area has not been much focused academically in the Sri Lankan context. The Ministry of Transport and Civil Aviation, National Transport Commission (NTC), Sri Lanka Transport Board (SLTB) and Sri Lanka Private Bus Owners Association will be the main organizations benefitted by this research in addition to passengers travelling in and out of Colombo.
item: Conference-Abstract
Optimization of anti-glare block spacing in expressways
(Department of Civil Engineering, University of Moratuwa., 2019-09) Dharmarathna, WGAD; Pasindu, HR; Pasindu, HR
Glare occurs when visual field brightness is greater than the luminance, to which eyes are adapted during driving. Glare can be occurred due to the approaching head lamps at night time / low light conditions. Visibility is required for a safe driving and any obstruction to the driver’s vision can affect the driving, resulting a threat to the roadway safety. Glare is a significant factor causing vision obstructions. Hence, driving at night can be more hazardous and difficult compared to the day time as the headlight glare reduces the visibility of vehicles while causing fatigue to the driver. Effective reduction of glare by utilizing anti-glare blocks will be helpful to address this issue. Considering the movement of high speed vehicles in the expressways (Design speed of Sri Lankan expressways =100kmph) and other design parameters, the provision of anti-glare blocks can be justified as a solution for the reduction of glare. However, anti-glare blocks do not work well in rolling alignments with vertical curvatures. Furthermore, anti-glare blocks can restrict the vision of opposing carriageways while affecting the surveillance and the safe utilization of emergency crossing points. According to the recommended technical standards, the initial selection of the suitable type of anti-glare blocks are done considering the light screening/cut-off angle (α), the width of the blocks, the spacing of the blocks, and the height of the blocks. As per the British standards (BS EN12676-1:20000), the recommended range of the cut-off angle (α) for straight sections is tan α ≥ 0.33. For curved sections, the degree of curvature at the center of the curve should be added to the above value. Recommended width of the blocks ranges from 200 mm – 300 mm. Cost of installation and aesthetically pleasing appearance should also be considered during the selection of the width of the blocks as they are installed on the top of NJBs, on the sides of half NJBs, on the guard rails, and on narrow center medians. British standards recommend (BS EN12676-1:20000) the non-glare height for straight sections to be 1.80 m above the finished surface of the road. Height of the anti-glare blocks depends on many factors like number of lanes, median width, head light distance for maximum glare, and height of driver’s eyes. Apart from the design parameters, other factors contributing for the selection of anti-glare blocks are; cost of installation, method of installation, minimum cleaning requirements, aesthetically pleasing appearance, and reduced weight (At an event of impact, the debris is light and non-metallic). Since the country does not have a proper guideline for the selection of the optimum spacing for anti-glare blocks, it is complicated to conduct a selection process for the Sri Lankan context. Optimum spacing is not site specific and a general spacing value for expressways may not be economical as well. A model to determine the optimum spacing of anti-glare blocks was proposed by this study and it will ensure the safety and comfort of the roadway users.
item: Conference-Abstract
Development of pavement condition prediction model for national highways
(Department of Civil Engineering, University of Moratuwa., 2019-09) Sandamal, RMK; Pasindu, HR; Pasindu, HR
National Highways are basic infrastructure which provide the connectively for the urban development in a country. An accurate pavement performance prediction model is essential for pavement asset management systems to optimize the life cycle cost of preventive and corrective maintenance strategies. In this study, pavement roughness and relevant distresses progression of national highways in the long-term pavement performance data was analyzed to develop such a pavement condition prediction model. International Roughness Index (IRI) is a global parameter to measure the ride comfort of road users and unevenness of pavement, therefore use as the basis for the pavement prediction model in this research. High intensity of repetitive axle loading, and aging effect caused for the failure of pavement and distresses related to traffic load and aging are developed, hence pavement roughness is increased while distresses are propagated. Structural failure, functional failure due to the non- smooth riding surface are the reasons for increasing of vehicle operating cost (VOC) and waste of resources. The relationship between roughness and relevant distresses progression with pavement age was developed and validated with comparing such models developed by previous studies. The pavement distresses progression with the pavement age is analyzed by using regression analysis. Three curves are plotted to express the pavement deterioration, in that roughness deterioration curve is developed by considering the initial construction quality. Those deterioration models can be used to calibrate HDM-4 software to adopt for the local condition as a decision-making tool for the maintenance and rehabilitation work. Increasing of roughness is a function of progression of distresses which is use for the model calibration process in HDM-4 software as shown in equation 1. ΔRI= Kgp + ΔRIs + ΔRIc + ΔRIr + ΔRIt + ΔRIe …….…………………(1) Where: Kgp - calibration factor of general surface roughness development, ΔRI - gradual increase of pavement surface roughness, ΔRIs - structural pavement deterioration, ΔRIc – deterioration due to cracking, ΔRIr – deterioration due to rutting, ΔRIt – deterioration due to potholes, ΔRIe – deterioration due to climate effects From the results of the study, the components of roughness deterioration due to the pothole (ΔRIt) and cracking (ΔRIc) are established. Combination of deterioration due to the structural condition, climate effect and rutting are representing as a constant. The findings from the research can be used to HDM-4 model calibration of roughness increasing of national road network in Sri Lanka instead of using default values which are currently use for the pavement performance modelling.

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