Generalized Link-Cost Function and Network Design for Dedicated Truck-Platoon Lanes to Improve Energy, Pavement Sustainability, and Traffic Efficiency

Recent development of autonomous and connected trucks (ACT) has provided the freight industry with the option of using truck platooning to improve fuel efficiency, traffic throughput, and safety. However, closely spaced and longitudinally aligned trucks impose frequent and concentrated loading on pavements, which often accelerates pavement deterioration and increases the life cycle costs for the highway agency. Also, effectiveness of truck platooning can be maximized only in dedicated lanes; and its benefits and costs need to be properly balanced between stakeholders. This paper proposes a network-design model to optimize (i) placement of dedicated truck-platoon lanes and toll price in a highway network, (ii) pooling and routing of ACT traffic from multiple origins and destinations to utilize these lanes, and (iii) configuration of truck platoons within these lanes (e.g., lateral displacements and vehicle separations). The problem is formulated as an integrated bi-level optimization model. The upper level makes decisions on converting existing highway lanes into dedicated platoon lanes, as well as setting user fees. The lower-level decisions are made by independent shippers regarding the choice of routes and use of platoon lanes vs. regular lanes; and they collectively determine truck traffic in all lanes. Link-cost functions for platoon lanes are obtained by simultaneously optimizing, through dynamic programming, pavement-rehabilitation activities and platoon configuration in the pavement's life cycle. A numerical case study is used to demonstrate the applicability and performance of the proposed model framework over the Illinois freeway system. It is shown that the freight traffic is effectively channelized on a few corridors of platoon lanes and, by setting proper user fees to cover pavement-rehabilitation costs, systemwide improvements for both freight shippers and highway agencies can be achieved.

Advantages and limitations of using foamed bitumen

Foamed asphalt refers to a bituminous mixture of road-building aggregates and foamed bitumen, produced by a cold mix process. There are a lot of related issue that has not been sufficiently investigated so far. It is worthwhile to overview the main theoretical and practical results in the field in several countries including those of the authors of the paper. It is clear that the foamed asphalt is usually characterized by high quality and reasonable cost, can be used in cold road pavement rehabilitation, in addition to it the technique is environ-mentally friendly preserving natural resources. Using foamed bitumen reduces the emissions of carbon dioxide and gases resulting from combustion, especially when it is used as a cold rehabilitation binder and mixed with re-claimed asphalt pavement materials.

Determination of Dynamic Modulus Master Curve of Damaged Asphalt Pavements for Mechanistic–Empirical Pavement Rehabilitation Design

For pavement rehabilitation design, the current mechanistic–empirical (ME) pavement design guide provides three levels of analysis methodology to determine dynamic modulus master curves for existing asphalt pavements. First, the ME pavement design guide recommends that Witczak’s predictive equation is employed to obtain the “undamaged” modulus master curve. Depending on the chosen level of analysis, either a falling weight deflectometer test (Level 1) or a condition survey (Levels 2 and 3) is conducted to determine the damage factor(s). The damage factor is used to shift the undamaged master curve downward to match the field conditions and obtain the “damaged” master curve. In this study, two pavement structures in North Carolina Highway 96 were selected to evaluate the accuracy of the ME pavement design guide using its three levels of analysis. Because this roadway is a multilayer full-depth pavement, the extracted field cores were divided into a top layer, bottom layer, and total core for investigative and comparative purposes. Accordingly, both laboratory measurements and pavement ME predictions of the dynamic modulus values were conducted separately. Results show that the predicted undamaged master curves are always higher than the measured master curves and Levels 1, 2, and 3 can each lead to significantly different damaged master curves. Considering both efficiency and accuracy for transportation agency practice, the Level 1 method is recommended, and if the existing pavement is a multilayered asphalt pavement, a total core extracted from all the layers is recommended to generate the input properties for Witczak’s predictive equation.

Analisis Efisiensi Penggunaan Teknologi Aspal Daur Ulang Pada Jalan Tol Elevated Ir. Wiyoto Wiyono

The use of recycling technologies to the principles of green roads should get priority. Reclaimed Asphalt Pavement (RAP) has not been used properly is a problem in this study. Hotmix Recycling is a recycling technique that can be applied to road pavement rehabilitation and maintenance. The research was conducted to determine the cost-efficiency of recycled asphalt. The method used in this research is to analyze the unit price of conventional asphalt maintenance and to analyze the unit price of recycled asphalt in order to find out how much efficiency is obtained of asphalt pavement recycled. The results showed that the cost of conventional asphalt is Rp.1,160,000 per ton and the price of recycled asphalt is Rp.915,000 per ton, there is a savings of Rp. 245,000 per ton, The use of recycled asphalt technology in the periodic asphalt of the Ir. Wiyoto Wiyono toll roads can save operational and maintenance costs of Rp. 3,013,500,000.00