International Journal of Transportation Engineering
Volume:11 Issue: 4, Spring 2024

Today, one of the most significant points of interference in streets is the signalized intersections; therefore, solving problems of traffic at intersections can increase the capacity of urban transportation. Inability to diagnose the traffic conditions results in the lack of proper timing, phasing and cycle length, all of which are attributed to the abnormal factors concerning intelligent control systems. In this paper, in addition to the introduction of abnormal traffic conditions at signalized intersections, an attempt has been made to intelligently diagnose anomalies for both an approach and its entire intersection. For this purpose, by making use of the data based on the GPS of users' cell phones extracted from NESHAN Application, which consists of 10-minute average speed in streets ending to an intersection, and by behavioral matching with the data concerning the volume and saturation rate in SCATS, and meantime, by analyzing the fundamental traffic relations, an attempt has been made to diagnose the abnormal traffic conditions through SCATS at Toos-Danesh intersection of Mashhad, in which abnormal conditions including the detecting of heavy traffic conditions when the traffic is light and vice versa. To achieve more accuracy, the method was built based on both quartiles and percentiles of DS, degree of saturation, and ADS, average degree of saturation, in SCATS. Finally, anomaly detection based on the 10th and 90th percentiles had 100 percent accuracy and the one based on the 1st and 3rd quartiles had between 57 to 80 percent accuracy, which have been checked by two real datasets.

The prevailing conditions in the country, such as currency depreciation, escalating prices of technical equipment, and faulty execution of the privatization process, significantly influence the progress of road construction projects and the performance of contractors. Identifying these effective factors and understanding their significance is essential for enhancing and developing road construction projects. This study aims to identify the factors that affect the performance of contractors and categorize them into four main categories: financial, technical, operational, and managerial. A total of 19 factors have been identified. Furthermore, we have collected the viewpoints of experts in road construction regarding these 19 factors. The Analytic Hierarchy Process (AHP) technique, in conjunction with Expert Choice software, was deployed to evaluate the impact of each factor in the four main categories, as well as the impact of each of the 19 factors on project progression and the performance of road construction contractors. A sensitivity analysis was also conducted to assess the significance of these factors.

Due to the traffic structure in Iran and the excessive occurrence of loads to the surface of the pavement and then to the lower layers, the need to implement a resistant layer against to traffic loads in different weather conditions is quite obvious. In recent years, the upward trend in repair and maintenance costs for pavements has been increasing due to the increase in the amount and frequency of traffic loads on pavements, has led to an increase in the tendency to use modified asphalt mixtures, especially in areas with high traffics. Many studies have been done to identify the appropriate additive for use to improve the behavior of bitumen and mixtures. The efficiency and effect of Nano Al2O3 as additive in bitumen and rubberized asphalt mixtures in order to improve their performance against external loads and environmental factors was evaluated in this study. In order to achieve the objectives of this study, bitumen with different percentages of Nano Al2O3 (0, 0.5, 1.0 and 1.5%) was combined and subjected to physical and rheological tests. Also, for evaluating the functional properties of nano modified samples, various experiments were carried out including 4point bending fatigue test and wheel track. The results of this study show that improving the bitumen behavior in moderate and high temperatures can be led to decrease of fatigue and rutting failure in asphalt mixtures. Evaluation on the results showed that using of 20% rubber powder and 1.5% Al2O3 has the best effects on the rheological behavior of bitumen. Also using of this bitumen can improve the asphalt mixture fatigue behavior.

The aggregate particles in asphalt mixtures get connected by (bitumen + mineral filler) mastic. The goal of this paper is to study the feasibility of partial and total substitution of Limestone (LS) filler by Barite powder (BP) in Stone matrix asphalt (SMA) mixtures. To evaluate barite powder performance, resilient modulus, indirect tensile strength, freeze-thaw cycles, dynamic creep at two different temperatures, and bitumen draindown tests were used. The obtained values revealed that an increase in barite powder content from 50% to 100% improved the Stone matrix asphalt mixture moisture performance by 4.5% after going through 5 freeze-thaw cycles while on the other hand, it had an 18.5% reverse effect on the permanent deformation in higher temperatures. Also, despite barite powder's positive effect on bitumen draindown compared to the control samples; it could not yet thoroughly control SMA bitumen draindown.

Pavement functional and structural parameters are important for pavement evaluation. This research aims at developing a prediction model to predict the deflection of flexible pavements using International Roughness Index (IRI) values to optimize maintenance activities without conducting deflection testing. For this purpose, Multan-Lodhran south bound section, a part of N-5 is selected as study area. It starts from km 929+000 and ends at km 867+000, having a length of 62 km, dual carriageway having two lanes each side. The data used for this study had been collected from the database of Road Asset Management Division (RAMD), National Highway Authority, Islamabad, Pakistan on basis of data availability and reliability. Collected data includes International Roughness Index (IRI) values measured by profilometer and deflection data measured by Falling Weight Deflectometer (FWD). Existing pavement structure data was collected from NHA Regional office. Linear and Logarithmic Regression analysis methodology using SPSS Statistical Analysis Software was used to develop correlation between pavement functional and structural parameters for flexible pavement. Also, Microsoft Excel was used for data analysis and validation purpose. The developed regression model showed significant relationship between deflection and IRI. Additionally, AASHTO Back calculation method was also used for determining the effective structure number (SNeff) using deflection results from FWD to determine correlation of IRI with another structural parameter. Considering this, a significant correlation was found between SNeff and IRI. However, it was found that other parameters i.e., subgrade resilient modulus (Mr) and pavement elastic modulous (Ep) did not show any significant relation. The result showed that if pavement IRI values are known, deflection and SNeff can be predicted providing feasibility for transportation agencies that do not have the capabilities as deflection tests are costly and require sophistication for its data handling.

The integrated management of transportation in the current era is multifaceted, requiring interdisciplinary cooperation in all dimensions for success. The transportation system management face new challenges due to the growth of cities and the rise of car usage. The problem can be solved with different solutions, such as referring to traditions of urbanization (neo-traditional). As part of urban planning management strategies for revitalizing neo-traditional regions, this paper examines three scenarios of traffic islands, increasing specific uses per capita, and traffic calming. Using the four-stage transportation models calibrated for the case study, Mashhad city, V-Km, travel time, CO pollutant and fuel consumption are measured. The analysis of the quality indicators affected by neo-traditionalism, which are hard to quantify, so ranking them according to fuzzy Delphi technique. Due to some shortcomings, the Ground theory method was finally used to model and identify the qualitative indicators. According to VISSUM output, the 20% increase in travel attraction resulted in a 2.82% and 1.93% reduction in travel time in zones and city, respectively. However, CO emissions have increased by 0.94% in the zones and decreased by 0.62% in the whole city. Fuzzy Delphi technique shows in scenario two, the neighbourhoods economic prosperity, social interaction, and satisfaction have the highest score. According to the Grounded theory model of neo-traditionalism in the regions, which was developed based on interviews with a significant number of elites, strengthening walking, increasing density in residential areas, connecting urban roads, and creating mixed land use are the essential strategies based on neo-traditionalism.