Point-based rut bar systems are commonly used by transportation agencies. However, potential measurement errors exist in these systems because of the limited number of sample points (e.g. 3 to 31 points). Now, advanced sensing technology can acquire high-resolution transverse profiles of more than 4,000 points using 3D line laser imaging technology (termed the 3D line laser hereafter). This study, sponsored by the United States Department of Transportation (USDOT) Research and Innovative Technology Administration (RITA) program, is a) to explore the feasibility of using the 3D line laser to accurately and reliably measure rut depth, and b) to quantify the potential rut depth measurement errors using point-based rut bar systems. The rut depth measurement accuracy and repeatability of the 3D line laser were validated in laboratory and field tests. Results show that the absolute rut-depth measurement error is less than 3 mm, and, therefore, the transverse profiles acquired by the 3D line laser can be used to quantitatively evaluate the accuracy and reliability of point-based rut bar systems. Rut bar systems having 3 to 31 sensors were simulated using transverse profiles acquired by the 3D line laser. Test results show that the relative rut-depth measurement error generally decreases with the increasing number of laser sensors. However, the trend is unclear for rut bar systems with fewer sensors because the rut shape affects the rut depth measurement error more than the number of sensors. Thus, a 3-point rut bar system could outperform a 5-point system occasionally. Test results also show that the commonly used 3-point and 5-point rut bar systems can underestimate rut depth by 16% to 51% and 22% to 64%, respectively. The relative rut-depth measurement error is less than 10% only when the number of sensors is greater than 29.

Assessment of Rut Depth Measurement Accuracy of Point-Based Rut Bar Systems Using Emerging 3D Line Laser Imaging Technology

This paper describes the usefulness of FEM for exploring the parameter sensitive analysis. Using 2D axisymmetric analysis, the critical performance parameters are examined by varying the thickness and material properties of different layers of flexible pavement. Hypothetical pavement sections are also analyzed with a view to check the sensitivity of horizontal axisymmetric extent and refinement of mesh. The developed computer program after validation is used to calculate the horizontal tensile strain at the bottom of the bituminous layer (BL) and the vertical compressive strain at the top of the subgrade. These computed strains are incorporated in the fatigue and rutting criteria recommended in Indian Road Congress (IRC: 37-2012) to estimate the pavement life for various hypothetical conditions. Tensile strain at the bottom of BL and compressive strain on top of the subgrade decreases with an increase in the thickness of BL, which results in increase of fatigue and rutting lives. An increase in thickness of the base layer and the increase in its elastic modulus reduces the damage due to rutting, while it has less effect on damage due to fatigue. Such type of analysis proves beneficial for designing a pavement, keeping equilibrium between fatigue and rutting lives.

Parameter sensitive analysis of flexible pavement

The article highlights that glass fiber reinforced concretes (GFRC) can meet the requirements of Smart City better than ordinary concretes. The comprehensive discussion on GFRC composition is presented together with the review of glass fibers' influence on various concrete properties. First of all, because of their bridging abilities, they can limit the width, length, and total area of cracks. Additionally, GFRC are characterized by enhanced tensile, flexural, and splitting strength; impact, abrasion, spalling, fire, and freeze-thaw resistance as well as ductility, toughness, and permeability. All of this positively influences the mechanical behavior, durability, and corrosion resistance of concrete elements. Moreover, decreased thermal conductivity allows for better energy performance from the building's point of view. This results in cheaper structures both in manufacturing and maintaining even though GFRC are more expensive materials. However, mechanical properties enhance as long as sufficient workability and uniform fiber distribution are assured. From the environmental point of view, GFRC are eco-friendlier materials than ordinary concretes since their application can decrease the emission of CO2 by 17%. The article also describes the GFRC application fields and emphasizes the possibility of the creation of not only structural elements mainly intended for load transferring but also elements accompanying the building process, as well as elements of small architecture that make public spaces more attractive, durable, and safer. Owing to greater design and shaping freedom, GFRC can also better fulfill the needs of habitants of Smart City. 

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Glass Fiber Reinforced Concrete as a Durable and Enhanced Material for Structural and Architectural Elements in Smart City—A Review

The paper provides a state-of-the-art review of different conditions influencing the behavioral aspects of flexible pavement. The conditions which influence the pavement behavior are loading intensities and tyre pressure intensity, environmental conditions, surface and subsurface temperature, seepage, thickness combinations of different component layers, material properties, etc. Current pavement design and analytical procedures are discussed and questioned. The life of the road is theoretically designed for repetition of standard axle load, wherein, negligence in consideration of overloaded vehicles and high tyre inflation pressures even up to 1 MPa is noticed. The latest developments in the design and analytical procedures of pavements are highlighted. An overview of finite element modeling efforts involving different aspects is also presented. A combined effect of various actual conditions in the field affecting the pavement performance needs to be studied in details, therefore, there is a demand for an application of analytical tool which can accommodate the details of the complex system. In this connection, it should be noted that the versatile finite element solution technique holds a bright promise. Therefore, it is proposed to discuss at length the application of the finite element method towards the design of the flexible pavements.

A State-of-the-Art Review of Different Conditions Influencing the Behavioral Aspects of Flexible Pavement

Energy harvesting is a process that captures unused ambient energy such as heat, vibration, stress or movement that would otherwise be lost. Highway pavements infrastructure exposed to energy-potential resources from vehicle vibrations and traffic loading strains that could be harvested. Piezoelectric transducers (PZT) are potential materials for harvesting energy from pavements as they convert mechanical loading strains into electric voltage. For this purpose, this study is aimed to evaluate two types of piezoelectric prototypes integrated within asphalt mix; cylindrical disks and thin film sheet, suitable for compression and bending state of stresses, respectively. Finite element (FE) analysis was conducted to simulate prototype response in different geometry under dynamic loading. The evaluation of the prototype involves laboratory testing of their power output as a function of stress, and FE simulation of their mechanical behavior. Results suggested that power output is highly dependent on loading frequency and magnitude and PZT geometry but could be promising in powering low-watt LED traffic lights and wireless sensors embedded in pavement particularly in remote areas.

Advancement in the Design and Performance of Sustainable Asphalt Pavements

Fatigue (due to traffic repetitions) and rutting are the two distinct modes of failures in asphalt pavements. These two distresses are generally considered separately in pavement design, reliability studies and distress prediction models. It is interesting to study whether occurrence of fatigue cracking and rutting are related to each other; that is, whether a significant level of rutting is expected on a pavement which also shows significant level of fatigue cracking and vice versa. Given that mechanisms of progression of fatigue and rutting are quite complex, the present paper explores the LTPP (Long Term Pavement Performance) database to seek an answer to this question from phenomenological standpoint. A total of 97 data-points have been chosen from 59 LTPP sections with varied levels of fatigue and rutting distresses. The LTPP sections are those that have not undergone any maintenance or rehabilitation after construction, till the time considered in the study. Analysis of results shows that rut depth increases with the increase of fatigue cracking up to a fatigue cracking level of about 5%; after that the extent of rutting almost stabilizes and does not show significant increase with the increase in fatigue cracking.

Are Fatigue and Rutting Distress Modes Related

The combined influence of traffic and environment causes every pavement to deteriorate over time. Maintenance actions help to delay the rate of pavement deterioration. Pavement maintenance demand large amount of fund, resources and time. Prioritization of maintenance work enables to allocate fund and resources in an effective way based on the performance evaluation of the pavement section(s). There are different maintenance prioritization mechanisms exist to evaluate a pavement. From the review of past literature, it is observed that fuzzy logic has not been used to evaluate interlocking concrete block pavements (ICBP). This research is an attempt to implement fuzzy logic for the purpose of maintenance prioritization on ICBP. The distresses of ICBP considered in this study are rutting, depression and damaged paver blocks. The distress density is given as inputs in the fuzzy prioritization model. The outputs are the pavement condition index (PCI) and the maintenance strategy to be adopted. An experts’ survey was conducted to define the boundaries of the membership functions of the input (distresses) and output (PCI and maintenance strategies) parameters. The triangular membership function is used in this study. The maintenance strategies suggested are routine and preventive maintenance, major and minor rehabilitation and reconstruction. The fuzzy model developed in this work has been demonstrated with a case study.

Maintenance prioritization of interlocking concrete block pavement using fuzzy logic

Effect of recycled aggregate and flyash on glass fiber reinforced concrete

Various manual and automated methods are used for the measurement of rut depth of an asphalt pavement. It is observed that different methods of rut depth measurement give different values of rut de...

Ripunjoy Gogoi

Papers

Are Fatigue and Rutting Distress Modes Related

Maintenance prioritization of interlocking concrete block pavement using fuzzy logic

Effect of recycled aggregate and flyash on glass fiber reinforced concrete

Rut depth measurement of an asphalt pavement from its original profile

An Experimental Investigation on the Impact of Basalt Fibres on Recycled Aggregate Concrete