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Models developed in Highway Capacity Manual (HCM) are not suitable to cater to the effects of mixed traffic conditions and hence, its use is unjustifiable. This research investigates such a challenging problem as the effect of undesignated pedestrian crossings on the entry capacity of roundabouts. For the present study, field survey data were collected using video cameras from three roundabouts such that the base section (roundabout without pedestrian influence) and non-base sections (with pedestrian influence), both scenarios, were captured. A modified HCM equation was developed to estimate entry capacity and further, the reduction in capacity with respect to pedestrian volume is determined. Lastly, a relationship was developed to check the effect of pedestrian crossflow on the entry capacity. The relation shows that capacity reduced to 1841 Passenger Car Unit (PCU/h) when the pedestrian flow increased to 288 pedestrians/hour. [ABSTRACT FROM AUTHOR]

Pedestrian crossing activity at unmarked crosswalks on urban roads in developing countries like India is a common phenomenon. Pedestrians used to cross the road at their place of interest to access residential and commercial land use. Such crossing operations cause a twofold effect: first the pedestrian put themselves at high risk of collision with the moving traffic, and they also affect the normal traffic operations, which causes excessive delay to vehicular traffic. Available pedestrian crossing warrants (PCWs) based on PV2 (where P is the volume of crossing pedestrians per hour and Vis per-hourly traffic volume) focus on the safe movement of pedestrians, but traffic operation is least considered in such warrants. The present study deals with the development of pedestrian crossing facility warrants based on pedestrian safe movement along with vehicular delay, which includes traffic efficiency as well. The traffic data collected from four different locations through the videographic survey were used for evaluating the delay for the individual vehicle due to pedestrian crossing activity. The delay thus evaluated was further validated using the probe vehicle data collected during the same observation period. The vehicle was fitted with the GPS-based performance box instrument that provides the vehicle trajectory at any instance. A significant number of sample data were collected with the probe vehicle and delay was determined using trajectory data. The finding of the delay obtained from the field data was validated incorporating a simulation-based analysis to resemble the interaction of pedestrian flow dynamics with vehicular flows. The crossing behavior of pedestrians was simulated using microscopic simulation software VISSIM. The microsimulation model was first calibrated and validated for field traffic conditions. The total delay was assessed for the traffic stream, and it was found to follow a second-degree polynomial relationship with PV2 values. The clustering analysis was carried out using K-means clustering to define a threshold value for pedestrian crossing facilities. These warrants were also identified based on PV2 utilizing the relationship between total delay and PV2 values. The results of the present study will be useful for practicing engineers for designing pedestrian crossing facilities considering pedestrian safety and vehicular operation as well. [ABSTRACT FROM AUTHOR]

Pedestrian crossing at midblock sections of urban roads at undesignated places is a normal phenomenon in developing countries. These locations are undesignated places, i.e., not marked with any zebra crossing, pedestrians' signals or grade-separated facility. Still the Pedestrians cross the road to access their desired place in order to save time which negatively affects traffic movement. The present study attempted to quantify the reduction in capacity of 6-lane and 4-lane divided urban arterial roads due to such crossing maneuver by pedestrians. Capacity of base section, i.e., section does not have pedestrian cross-flow or any other factors influencing traffic flow, is determined from field data. These capacity values are compared with the capacity of section under the influence of pedestrian crossing. Data were collected on twenty-two different locations of 4-lane and 6-lane urban arterials in five different metropolitan cities. The speed–volume data are extracted from field data in order to find out the capacity of base sections and friction sections. The mathematical equation has been developed showing the relationship among pedestrian cross-flow and capacity drop. It has been found that there is no impact on capacity when pedestrian cross-flow is limited to 200 pph (pedestrians/hour). However, the capacity reduces by 32% when pedestrian cross-flow is raised to 1550 pph. Further, the safe pedestrian crossing facilities are recommended based on pedestrian and vehicular volume analysis. [ABSTRACT FROM AUTHOR]

Pedestrian crossing at undesignated midblock locations is a prevalent phenomenon in developing countries like India that adversely affects the traffic performance of such sections. The present study aims to determine the effect of such pedestrian crossings on traffic characteristics like vehicular speed and capacity of the section. Data was collected on six-lane urban arterial midblock sections in six different metropolitan cities in India. Fifteen such sections were selected, with and without the presence of crossing pedestrians, and named base and friction sections, respectively. Speed models were developed for the sections, and from the speed models, the capacity of base and friction sections was estimated with varying pedestrian crossflow. The model capacity values were further validated by collecting field data at six more sections--three base sections and three friction sections. The model capacity values were in good agreement with the field capacity values, with mean absolute percentage error (MAPE) values less than 6% for both data sets, that is, for base and friction sections, respectively. [ABSTRACT FROM AUTHOR]

Pedestrians are the most vulnerable road users, and pedestrian safety has become a major concern among researchers in recent years due to the increasing number of road fatalities. Conflict analysis using surrogate safety measures (SSMs) helps study pedestrian safety, as there are several limitations with collision data. Moreover, it is a cost-effective technique compared to historical crash data analysis. The present study analyses pedestrian safety at urban midblock crosswalks using time-tocollision (TTC) as SSM. The data for the present study were collected from four different midblock pedestrian crossing locations in different cities in the western part of India using the videographic technique. The trajectory of pedestrians and vehicles was extracted for micro-level analysis of pedestrian--vehicle interactions. The trajectory data were further used to calculate TTC at regular time intervals during the interaction of pedestrians and vehicles. Two different types of pedestrian road crossing behaviour, viz. vehicle pass first and pedestrian pass first were identified, and TTC analysis was carried out differently for each scenario. The variation of TTC based on gender and vehicle category was analysed to evaluate the influence of such parameters on pedestrian safety. The generalized linear mixed model approach was used to develop linear regression models for TTC based on empirical data. The threshold values for TTC were used to define various safety levels of pedestrians using a clustering approach. [ABSTRACT FROM AUTHOR]