International Journal of Transportation Engineering
Volume:11 Issue: 1, Summer 2023

Transit-Oriented Development (TOD) is considered one of the most comprehensive urban theories concerning land use and transportation. Improving pedestrian access and urban public transport is a key objective of TOD, leading to an enhanced level of TOD within a given zone. This study aims to examine the impact of pedestrian access on public transportation, particularly through access to transit stations. A range of indicators related to pedestrian access to public transportation, such as the service area of public transportation, number of transport stations, speed, parking availability, commercial density, residential density, public spaces, walking distance, connectivity, transport modes, slope, and population density, were collected for this purpose. The quantitative values for these indicators were subsequently computed for District 6 of Tehran (selected as a case study) utilizing ArcGIS. The aim was to determine the correlation between these indicators and the percentage of trips made using public transportation within the zone, serving as a functional criterion for assessing the level of TOD in the area. Subsequently, a model for pedestrian access modes to public transit in different zones was developed using the multi-layered perceptron neural network (MLP) technique. Based on the results, the network output with R=0.9517 and MSE=4.8881 indicated the satisfactory performance of the model. Furthermore, the sensitivity analysis results revealed the highest impact to be associated with parking, while the lowest impact was attributed to public spaces.

In developing countries, the population of younger adults is relatively higher. In addition, the frequency of traffic violations, committed by young drivers, is considerable. Consequently, annually a large portion of road crashes is recorded among this age group. This paper aims to study the traffic rule violations of young drivers in Iran. Focusing on the behavior of young drivers and understanding the mechanisms that affect the occurrence of violations among this group of drivers can be helpful to promote traffic safety. For this purpose, 567 drivers in the range of 18 to 40 years old have been studied. Then, different data mining approaches such as descriptive analysis, correlation analysis, multinomial logistic regression (MLR), and Random Forest (RF) were used. The main contribution of this paper is using different analytic methods to gain insight into traffic violations of young drivers and to propose potential countermeasures to decrease this issue. Results indicated that driving over speed limits, red-light running, and angry driving are the most frequent violations. The frequency of using mobile phone while driving, as a source of distraction, has been found to be highly correlated with other violations. As the frequency of previous traffic fines, the number of days with access to private cars, and the frequency of previous crashes increase, more diverse types of violations with high frequencies are expected in the future. In addition, the frequency of risky violations was found to be higher among men and those with lower education levels.

Dramatic growth in motorcycle usage coupled with the riders’ high-risk driving behavior calls for a reform in motorcycle monitoring schemes in developing countries. In Tehran, Iran, about one million motorcycle license plates are registered in the city, of which more than 35% are unreadable, proving the existing monitoring schemes fall short in regulating motorcycle operations. A More Strict Plate Control (MSPC) is proposed to address the issue. While there is no question about the necessity of this policy, Tehran policymakers are concerned about the acceptance level of this policy. This study investigates its acceptance among motorcyclists, the major potential opponent population, in Tehran. To this end, 400 riders have been surveyed. Data analysis shows that subjective factors, such as driving behavior and attitudes, highly impact acceptance. Also, aggressive riders are more likely to disagree with the policy, but most of the motorcyclists did not disagree with a More Strict Plate Control (MSPC) Policy.

Rail transportation plays a significant role in the movement of commodities and passengers. The progressive demand for transporting passengers and commodities with limited capital available to develop rail infrastructure challenges the rail system ability for transportation by trains. There are two general ways to improve capacity in a route, including new investment in infrastructure and improving the performance of existing lines. In the present study, time management was used to increase the capacity of existing railways. A new rescheduling model is proposed in this research to overcome some of the current constraints called “Optimal increase in the capacity of lines.” This model uses the conflict solution technique and timetable compaction and can be used for one, two, and multi-line routes. A case study was conducted for part of a single-line BADROOD-ISFAHAN route, in which significant results were obtained. After process1, more than 25 initial timetable schedule conflicts were resolved in both Same Orders and Order Free approaches. After process 2, the OPTIMAL INCREASE model could compress the timetable by almost one hour and improve maximum dwell times (from 61to30 min) and total dwell times (from 271to168 min) of trains at stations. The total duration of the timetable was increased by almost 20 minutes. After process3, the OPTIMAL INCREASE model provided approximately 36minutes shorter timetable duration (better capacity utilization). Also, the results show that the duration of timetabled developed was slightly increased, mainly due to the sizable reduction in maximum dwell time from 61 minutes to 10 minutes.

Creating motivational factors is a way to increase bicycle use in a city where its share in transportation is low. The current study evaluated factors that could motivate an increase in shared bicycle demand. Results of a survey conducted in Tehran were used to identify the most influential factors. Next, Aimsun software was used to perform a simulation on two major streets in the city to assess the following scenarios: 1) without bicycles, 2) with bicycles and other vehicles, and 3) with bike lanes. The results showed that the entry of shared bicycles into the streets decreased the density of motor vehicles. On Jomhouri St, the density of motor vehicles decreased from 16.39 veh/km for without bicycles scenario to 13.52 veh/km for construction bike lanes. A downward trend also was observed for Keshavarz Blvd., with a decrease of 14.21% from scenarios one to three. The construction of bicycle lanes as a means of increasing public interest in sharing bicycles can have a positive effect on reducing traffic congestion.

Providing the mechanical properties of concrete used in road paving is of great importance. In the current study, Granulated Blast Furnace Slag (GBFS) based geopolymer concrete (GPC) was used with 0-2% polyolefin fibers (POFs) and 0-8% Nano Silica (NS) to improve its structure. After curing the specimens under dry conditions at a temperature of 60 °C in an oven, they were subjected to Tensile Strength, Modulus of Elasticity and Ultrasonic Pulse Velocity (UPV) tests to evaluate their mechanical properties. All tests were performed at 90 days of age under ambient temperature (20 ℃) and high temperature (500 ℃).  The addition of NS enhanced the whole properties of the GBFS-based GPC. Addition of up to 8% NS to the GPC composition at 20% temperature improved the modulus of elasticity test results by 13.42%, tensile strength by 15.19% and UPV by 11.58%. Addition of up to 2% of POFs to the composition of GPC improved the tensile strength up to 11.76%, modulus of elasticity 07.05% and UPV drop up to 12.02%. Applying high heat to GPC samples reduced the modulus of elasticity by up to 42%, tensile strength by up to 21% and UPV by up to 46%. The effect of heat on the drop in results in control concrete is more than GPC. In the following, by conducting the Scanning Electron Microscope (SEM) analysis, a microstructure investigation was carried out on the concrete samples. In addition to their overlapping with each other, the results indicate the GPC superiority over the regular concrete.