Different Types Of Pavements Research Articles

Evaluation of effects of pavement characteristics on the OBSI levels using Principal Components Regression

Tire/pavement noise is a major contributor to traffic noise at highway speeds. Tire/pavement noise is affected by different pavement properties. A study conducted in California measured the noise levels of different mix types and the mix characteristics affecting noise levels. In this study, tire/pavement noise was measured using the on‐board sound intensity (OBSI) method. Data was collected on four different types of pavement mixes: conventional open graded asphalt concrete (OGAC), rubberized asphalt concrete that are open graded (RAC‐O), rubberized asphalt concrete that are gap graded (RAC‐G), and dense graded asphalt concrete mixes (DGAC). A total of 72 field pavement sections were included in the study, all of which were less than 8 years old at the time of the measurements. This paper evaluates the pavement characteristics affecting noise levels using principal components regression. This technique was used due to the multicollinearity found among the variables. Two principal components were extracted from the measured parameters such as air void content, gradation properties, pavement roughness, age, and pavement surface condition.

Influence of pavement surface noise: the Korea Highway Corporation test road

Because of a significant increase in the number of vehicles using national highway networks that link major urban centers, road traffic noise—with its harmful impact on the environment—has become a major pavement system issue. Therefore, it is necessary to assess the characteristics of different types of pavement and their influence on road traffic noise. The Korea Highway Corporation test road, with eight different pavement surfaces, was used to test and analyze noise from tire–pavement interaction and from vehicle power trains. Noise was measured in a novel test approach using a surface microphone. The results show that traffic noise levels vary widely according to pavement surface type, vehicle type, and vehicle speed. The findings of this investigation can be used to determine appropriate pavement surfaces that will satisfy specific environmental impact assessments for given traffic conditions and requirements.Key words: road traffic noise, tire–pavement noise, power-train noise, surface microphone.

Exposure to Wear Particles Generated from Studded Tires and Pavement Induces Inflammatory Cytokine Release from Human Macrophages

Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. Lately, wear particles generated from traffic have been recognized to be a major contributing source to the overall particle load, especially in the Nordic countries were studded tires are used. In this work, we investigated the inflammatory effect of PM10 generated from the wear of studded tires on two different types of pavement. As comparison, we also investigated PM10 from a traffic-intensive street, a subway station, and diesel exhaust particles (DEP). Human monocyte-derived macrophages, nasal epithelial cells (RPMI 2650), and bronchial epithelial cells (BEAS-2B) were exposed to the different types of particles, and the secretion of IL-6, IL-8, IL-10, and TNF-alpha into the culture medium was measured. The results show a significant release of cytokines from macrophages after exposure for all types of particles. When particles generated from asphalt/granite pavement were compared to asphalt/quartzite pavement, the granite pavement had a significantly higher capacity to induce the release of cytokines. The granite pavement particles induced cytokine release at the same magnitude as the street particles did, which was higher than what particles from both a subway station and DEP did. Exposure of epithelial cells to PM10 resulted in a significant increase of TNF-alpha secreted from BEAS-2B cells for all types of particles used (DEP was not tested), and the highest levels were induced by subway particles. None of the particle types were able to evoke detectable cytokine release from RPMI 2650 cells. The results indicate that PM10 generated by the wear of studded tires on the street surface is a large contributor to the cytokine-releasing ability of particles in traffic-intensive areas and that the type of pavement used is important for the level of this contribution. Furthermore, the airway inflammatory potential of wear particles from tires and pavement might be of a greater magnitude than that of DEP.

Rational Estimation of Construction Impact on Pavement Performance

The goal in any highway construction project is to produce a durable pavement that will perform satisfactorily throughout its expected design life. The quality of construction also plays a significant role in accurately predicting the life-cycle performance. In that context, the quality of construction is defined as meeting a structural-related target variable with minimal variance. The implementation of effective performance-based construction quality management requires a tool for determining impact of construction quality on the life-cycle performance of pavements. This process should carefully consider that relevant parameters are different for different types of pavements. What is not so obvious is that for the same type of pavement, the relevant parameters change with the relative structure of the pavement. Many parameters that are important for a thick pavement designed for an Interstate highway may be of secondary significance to a secondary road. Simply put, defining one set of parameters that can be used in all projects is not appropriate because it may not be cost-effective. A statistical-based algorithm is presented; it was developed to reconcile the results from several pavement performance models used in the state of practice with systematic process control techniques. These algorithms identify project-specific parameters that should be the focus of the construction quality management by quantifying the variability of the construction parameters. The identification of these parameters allows for transportation agencies to focus their limited funds and resources more efficiently while increasing the life of the pavement.

Rational Estimation of Construction Impact on Pavement Performance

The goal in any highway construction project is to produce a durable pavement that will perform satisfactorily throughout its expected design life. The quality of construction also plays a significant role in accurately predicting the life-cycle performance. In that context, the quality of construction is defined as meeting a structural-related target variable with minimal variance. The implementation of effective performance-based construction quality management requires a tool for determining impact of construction quality on the life-cycle performance of pavements. This process should carefully consider that relevant parameters are different for different types of pavements. What is not so obvious is that for the same type of pavement, the relevant parameters change with the relative structure of the pavement. Many parameters that are important for a thick pavement designed for an Interstate highway may be of secondary significance to a secondary road. Simply put, defining one set of parameters that can be used in all projects is not appropriate because it may not be cost-effective. A statistical-based algorithm is presented; it was developed to reconcile the results from several pavement performance models used in the state of practice with systematic process control techniques. These algorithms identify project-specific parameters that should be the focus of the construction quality management by quantifying the variability of the construction parameters. The identification of these parameters allows for transportation agencies to focus their limited funds and resources more efficiently while increasing the life of the pavement.

Geomechanical Analysis of Unbound Pavements Based on Shakedown Theory

A procedure for analyzing the mechanical response of an unbound pavement to the repeated loading of traffic is presented. The pavement is modeled as a layered elastic/plastic structure, and its response is described by the concepts of shakedown theory. A critical shakedown load is identified as the key design parameter. Pavements operating at higher loads will eventually fail, and those operating at loads less than critical may initially exhibit some distress but will eventually shakedown to a steady state. Estimates of this critical load, for different types of pavement, are found by studying various types of failure mechanisms, such as rut formation and subsurface slip. Optimization procedures are then used to determine the most likely form of failure for a particular pavement. The effects of self-weight, dual loads, moisture content, relative strengths of the various layers, and nonassociated plastic flow are studied. Some preliminary implications for pavement design are discussed.

Assess Subgrade Rutting Potential by Stress Factor

The problem of subgrade rutting is an important factor in the overall structural design system of flexible pavements. This paper introduces the parameter stress factor in pavement design and research as an expedient and useful test to check the subgrade rutting potential in a flexible pavement. The larger the computed stress factor in the subgrade is, the greater the potential of the pavement to rut. If several different types of pavements are designed for a given subgrade soil and for a given aircraft load at the same performance level, the pavement with the largest stress factor will most probably have the greatest potential of subgrade rutting. Also for a given subgrade soil, if two pavements are designed for two different aircraft loads at the same performance level, the heavier aircraft load will have a greater stress factor in the subgrade.