Characterisation and modelling of pedestrian flows in hospital and academic environments

This paper examined pedestrian characteristics in two urban facilities namely a teaching hospital and a university campus. The aim was to determine if pedestrian flow features in these facilities differed from those in downtown areas. The objectives were to measure pedestrian flow rates and model their walking behaviour. Eleven sites located within these facilities were selected for study. The results indicated that the male walked faster than the female in the university campus while the female was faster in the hospital environment. Also the university campus saw more groups of pedestrians in the traffic mix than was the case in the hospital environment where 93% of the pedestrians were in single files. The male walked faster than the female by 7% in the university environment while the female were faster by 4% in the hospital environment. The modelling effort showed that the free walking speed in the university environment was 68.052 m/min with a critical density of 3.15 ped/m2. That of the hospital environment was 75.099 m/min and a critical density of 4.36 ped/m2. Since the speed-density relationships for the two facilities revealed a highly randomized plot, the data was fit to the normal distribution and pdf and cdf were used to assess the quality of the flow. For the university environment the results showed that 15% of the combined pedestrians walked below 56.88 m/min while 50% of the pedestrians walked below 66.67m/min and 85% walked below 72.50 m/min. Similarly, the results of the hospital environment showed that 15th percentile of the combined pedestrians walked below 69.75 m/min. The median speed of pedestrians was 72.50 m/min while 85% of the pedestrians walked below 75.25 m/min. In both cases, the 15 percentile speeds were 14% and 18.5% less than the median speeds in both facilities respectively. Thus flow breakdowns are unexpected in the two facilities

Review of traffic data collection methods for drivers’ car – following behaviour under various weather conditions

Adverse weather conditions have considerable impact on traffic operation and safety as it affects drivers’ car-following behaviour. However, the quality of traffic data and its related methodologies to address these effects are under continuous enhancement. This paper intends to provide an overview of various empirical traffic data collection methodologies widely used to investigate drivers car-following behaviour under various weather conditions. These methodologies include video cameras, pneumatic tubes, floating car data, instrumented vehicle and driving simulator. Moreover, the advantages and disadvantages related to methodologies have been discussed with emphasis on their suitability to work under adverse weather conditions. Furthermore, conclusion also comprises on table format of comparative review of facilities concerned with the methodologies

Modelling of pedestrian speed-density and volume-density relationships in outdoor walkways

The aim of this study was to model pedestrian flow parameters needed in the design of pedestrian facilities. The study also characterized the flow with a view to understanding pedestrian interaction problems especially with regards to their congestion. Twenty-five locations across Kano metropolis were selected for study, thirteen locations from the city district while twelve sites were chosen from the Waje district. All the sites were high flow pedestrian locations that met the study objectives. The data was categorized into four; young male, adult male, young female and adult female. The results indicated that adult women walked faster than their male counterparts in the City district while young males were faster than the female. The adult female recorded an average speed of 73.90 m/min against the speed of 71.30 m/min for the adult male. The average characteristics of the pedestrian in the city district are speed 67.30 m/min; density 11.23 Ped/m2 and volume 33.60 Ped/m/min. In the Waje district, however, the male pedestrian whether adult or young walked faster than their corresponding female counterparts with speed of 71.45 m/min for the adult male and 59.90 m/min for the adult female. The young male was faster than the young female by 17.9%. The average pedestrian flow parameters for the Waje district indicated a combine speed of 60.21 m/min; density of 8.72 Ped/m2 and volume of 30.92 Ped/m/min. The pedestrians in the city district had a higher flow rate, higher density and higher speed than those of the Waje district. This means the city district is a little more concentrated than the Waje district in terms of pedestrian flow. The aggregate average flow parameters of pedestrians in the metropolitan area gave the following parameters: speed 68.92 m/min; density 10.03 Ped/m2 and volume 32.33 Ped/m/min. The predictive models for Kano showed a free flow speed of 59.55 m/min and a maximum flow rate of 73.0 Ped/m/min. Comparing the Kano pedestrian model with other countries it was found that the Kano pedestrian walked slower than pedestrians from Singapore and the United States

Characteristics of vehicle headway during rainfall at night in Pontian, Johor

The headway pattern of a traffic stream has a significant impact on the accident possibility of the road section. The aim of this study is to determine the impact of different rainfall intensities have on the headway pattern in Pekan Nenas, Pontian, Johor. In this study, the automatic traffic count system (ATC) is utilised to obtain vehicle headway on the site. Rainfall data were obtained from the Department of Drainage and Irrigation, Pontian. The rainfall data was categorised into three rainfall intensity categories which are light rain, moderate rain and heavy rain. The traffic data and rainfall data then were then embedded to analyse the headway pattern of road user on the road section during rainfall at night. The results from the analysis showed that the headway pattern at night time followed the gamma distribution model. It was found that the mean vehicle headway increases as the rainfall intensity increases

Operating speed of vehicles during rainfall at night: case study in Pontian, Johor

Speed is one of the important parameters of traffic flow that can be used to determine the performance of driver’s behaviour under various scenarios. Changes in weather conditions caused changes in drivers’ speed due to various reasons. In Malaysia, there is slightly high number of road accidents at night. Rainfall at night does not only cause poor visibility to drivers, but it also gives a sense of insecurity especially as there is a significant reduction in the visibility of the object in front. Improper road conditions can worsen the situation, for example, rainfall can cause water accumulation on road surfaces which can increase skidding problem, potholes and hydroplaning effect. In relation to these situations, hence it is crucial to understand how the abrupt situation affect response of driver’s in terms of the macroscopic behaviour. These unpredictable environmental changes seem like portraying a very unpleasant journey for drivers especially to travel under rainfall condition at night. Therefore, there is a need to observe how individual vehicles react in terms of speed adjustment and response to the different rainfall intensities downpour at night. Hence this study was conducted to determine the impact of different rainfall intensities at night on vehicles’ speed. Traffic data was obtained using automatic traffic counter at a cross section of a road at Pengkalan Raja, Pontian for about three months during monsoon season. Rainfall data report was obtained from the Department of Drainage and Irrigation, Pontian. From this study, it was found that there is a speed reduction from the dry condition regardless of rainfall intensities at night. As rainfall intensities at night higher, the speed reduction is higher as well except for heavy rainfall condition. The mean speed, 15th percentile and 85th percentile of vehicles decrease with the increase in rainfall intensity at night. It can be concluded that rainfall have impact on vehicle’s speed irrespective of their intensities. Findings from this study can be used to help local authorities and transport planners in planning an efficient traffic management system for a safer travel experience to road users in Malaysia

Operating speed of vehicles during rainfall at night: case study in Pontian, Johor

Speed is one of the important parameters of traffic flow that can be used to determine the performance of driver’s behaviour under various scenarios. Changes in weather conditions caused changes in drivers’ speed due to various reasons. In Malaysia, there is slightly high number of road accidents at night. Rainfall at night does not only cause poor visibility to drivers, but it also gives a sense of insecurity especially as there is a significant reduction in the visibility of the object in front. Improper road conditions can worsen the situation, for example, rainfall can cause water accumulation on road surfaces which can increase skidding problem, potholes and hydroplaning effect. In relation to these situations, hence it is crucial to understand how the abrupt situation affect response of driver’s in terms of the macroscopic behaviour. These unpredictable environmental changes seem like portraying a very unpleasant journey for drivers especially to travel under rainfall condition at night. Therefore, there is a need to observe how individual vehicles react in terms of speed adjustment and response to the different rainfall intensities downpour at night. Hence this study was conducted to determine the impact of different rainfall intensities at night on vehicles’ speed. Traffic data was obtained using automatic traffic counter at a cross section of a road at Pengkalan Raja, Pontian for about three months during monsoon season. Rainfall data report was obtained from the Department of Drainage and Irrigation, Pontian. From this study, it was found that there is a speed reduction from the dry condition regardless of rainfall intensities at night. As rainfall intensities at night higher, the speed reduction is higher as well except for heavy rainfall condition. The mean speed, 15th percentile and 85th percentile of vehicles decrease with the increase in rainfall intensity at night. It can be concluded that rainfall have impact on vehicle’s speed irrespective of their intensities. Findings from this study can be used to help local authorities and transport planners in planning an efficient traffic management system for a safer travel experience to road users in Malaysia

Investigating the impact of rainfall on travel speed

The road network is particularly susceptible to adverse weather with a range of impacts when different weather conditions are experienced. Adverse weather often leads to decreases in traffic speed and subsequently affects the service levels. The paper is aimed at investigating the impact of rainfall on travel speed and quantifying the extent to which travel speed reduction occurs. Empirical studies were conducted on principle road in Terengganu and Johor, respectively for three months. Traffic data were collected by way of automatic traffic counter and rainfall data from the nearest raingauge station were supplied by the Department of Irrigation and Drainage supplemented by local survey data. These data were filtered to obtain traffic flow information for both dry and wet operating conditions and then were analyzed to see the effect of rainfall on percentile speeds. The results indicated that travel speed at 15th, 50th and 85thpercentiles decrease with increasing rainfall intensities. It was observed that allpercentile speeds decreased from a minimum of 1% during light rain to a maximum of 14% during heavy rain. Based on the hypothesis that travel speed differ significantly between dry and rainfall condition; the study found substantial changes in percentile speeds and concluded that rainfalls irrespective of their intensities have significant impact on the travel spee

Experimental evaluation of anti-stripping additives on porous asphalt mixtures

The open structure of porous asphalt mix influences its strength and durability against air, water and clogging materials. These factors cause loss of adhesion between binder-aggregate interface and loss of cohesion within the binder film. This could lead to stripping problem which contribute to premature failures as well as deterioration in the performance and service life of porous asphalt. Therefore, this study is aimed to evaluate the potential of diatomite as anti-stripping additives in porous asphalt and compared with hydrated lime and Ordinary Portland Cement (OPC). Field Emission Scanning Electron Microscopy (SEM) test and Energy Dispersive X-ray Spectroscopy analysis (EDX) were conducted to investigate the microstructure and chemical composition of the anti-stripping additives. A number of gyratory compacted samples of porous asphalt mixture with Malaysian gradation were prepared. Each sample was incorporated with 2% of anti-stripping additives as filler then mixed with polymer modified bitumen of PG76. The samples were measured for air voids content, permeability rate, resilient modulus and abrasion loss. The results indicate that samples prepared with hydrated lime show higher permeability rate and lower abrasion loss compared to samples with OPC and diatomite. However, the samples prepared with diatomite show enhanced resilient modulus compared to those with hydrated lime and OPC

Air voids characterisation and permeability of porous asphalt gradations used in different countries

This paper presents the evaluation made on the properties of porous asphalt mixtures practiced in different countries. In order to fully understand the properties of porous asphalt mixtures, investigation should be conducted from different perspectives. Therefore this study was carried out to investigate the air voids properties and functional performance of porous asphalt simultaneously. An image analysis technique was conducted to analyse the air void properties within the gyratory compacted samples captured using a non-destructive scanning technique of X-ray Computed Tomography (CT). The results were then compared to the functional performance in terms of permeability. Four aggregate gradations of porous asphalt used in different countries i.e. Malaysia, Australia, Singapore and the United States were adopted for comparison. From the analysis, Australian mixture was found with the most homogeneous air voids distribution throughout the sample compared to other mixtures. The air void properties investigated have successfully described the air voids formation within the mixtures which reflects the result of permeability. This shows that air voids distribution within the sample plays an important role in determining the effectiveness of water transmission

Effect of rainfall on traffic flow characteristics during night time

Understanding traffic behavior for obtaining a smooth, safe and economical traffic operation requires a thorough knowledge of traffic flow parameters and their mutual relationships.Eventhough adverse weather can reduce traffic efficiencies, there are still questions to answer regarding the relationship between weather conditions and traffic flow at night. This paper presents an investigation of the rainfall effects to the traffic flow characteristics on atwo-lane rural highway during night time. The traffic data and corresponding rainfall data for uninterrupted road segment of Federal route 3 at Dungun, Terengganu were collected under road lighting condition during the north-east monsoon season. The effect of good weather condition, light rain, moderate rain and heavy rain conditions on speed, flow and density were quantified and compared. Results from the analysis indicate that mean speed, mean flow and mean density are reduced under various rainfall conditions. In general, the impact of good weather and various rainfall conditions on Greenshield’s fundamental traffic flow relationship have weak correlations except for the relationship between flow and density. The important points in the fundamental diagram derived from flow-density relationships indicated that critical density, maximum flow, critical speed, jam density and free flow speed of roadway all decrease as rainfall intensity increases. It can be concluded that traffic flow characteristics of two-lane rural highway in Terengganu are affected by rainfall conditions