Combining Portable Falling Weight Deflectometer and Surface Wave Measurements for Evaluation of Longitudinal Joints in Asphalt Pavements

Abstract

Longitudinal joints in asphalt pavements typically have lower densities than the interior portion of the mat. Therefore, they tend to exhibit surface distresses such as cracking and raveling more rapidly. The objective of this study is to evaluate the ability of nondestructive testing (NDT) for assessing the relative condition of a longitudinal joint. NDT has been significantly developed for pavement evaluation during the past decade. Deflection and surface wave methods are the most commonly used for pavement evaluation. The portable falling weight deflectometer (PFWD) is increasingly used in quality control and quality assurance to provide rapid determination of the equivalent surface elastic modulus. However, the multichannel analysis of the surface waves (MASW) method consists of using ultrasonic transducers to measure surface waves traveling through the pavement and invert for the elastic modulus of different layers. This study presents results from both deflection and seismic methods to assess the quality of longitudinal joints. Both methods are performed at the same locations of the centerline of a test track. Pavement deflection is also measured on the wheelpath for comparison with previous data. Across the joint, changes smaller than 7% were observed in deflection values. These preliminary results cannot be directly related to joint quality because the contribution of sublayers to the modulus measured with the PFWD needs to be estimated. MASW measurements showed promising results for evaluating the attenuation of surface waves due to the joint. Further work is required to improve the coupling between the transducers and asphalt surface.

Microwave Absorbing Characteristics of Asphalt Mixes With Carbonyl Iron Powder

“…For example, Li and Soheil [6] used wave propagation techniques to determine the degree of aging of hot-mix asphalt (HMA) and thought that the nondestructive techniques made it attractive to monitor the variation in modulus of an HMA specimen. The multichannel analysis of the surface waves (MASW) method was used to measure pavement depth by measuring the elastic modulus of different layers [7,8]. In addition, microwave techniques have also been widely used to estimate initial setting time of cement paste and to enhance mechanical properties of cement matrix materials, etc.…”

Efficient Calibration of a Laser Dynamic Deflectometer

“…In order to measure the bearing capacity of road pavements, various research efforts have been made in the past three decades, and several kinds of systems have been developed, e.g., Falling Weight Deflectometer (FWD) [1]- [4], Light Falling Weight Deflectometer (LWD) [5]- [7], Rolling Dynamic Deflectometer (RDD) [8]- [10], Rolling Wheel Deflectometer (RWD) [11], and Road Deflection Tester (RDT) [12], etc. However, most of them have limitations in the practice of road testing due to several reasons, e.g., high operation cost, low efficiency, low safety, traffic interruptions, etc.…”

Advancements in active surface wave methods: modeling, testing, and inversion

“…The near-surface stiffness profiling of soils (e.g., Park et al 1999a), the method was also applied to pavements using multiple geophones by Park et al (2001b), and later using multiple accelerometers by Tertre et al (2010). To reduce the cost and inconvenience of coupling multiple receivers to pavement in MASW, the MSOR method was developed and applied to pavement stiffness profiling by Ryden et al (2001), Ryden et al (2002aRyden et al ( , 2002b, Park et al (2002), Olson and Miller (2010), and Lin and Ashlock (2011).…”