Pavement Integrity Scanner to Characterize Modulus Contrast between Near-Surface and Deeper Material in Concrete Pavements

Abstract

A major distress problem in rigid concrete pavements is early deterioration of near-surface layers. The quality of near-surface material governs the long-term performance of concrete pavement. If the near-surface material of the concrete layer is cured sufficiently well at an appropriate moisture and temperature, the concrete pavement system can be expected to endure fatigue loading of traffic throughout its design life span. A field measurement device, referred to as a pavement integrity scanner (PiScanner), was developed for use in quality control and quality assurance programs for concrete layers of pavement systems. PiScanner is based on the enhanced resonance search (ERS) technique, which evaluates the vertical variation of elastic modulus or compressive strength of the concrete layer in pavement systems. This information can be used in the construction period of a concrete pavement to evaluate the curing process of near-surface materials. In the implementation of the PiScanner, two design schemes were incorporated: a dedicated hardware device to perform measurements and an automated analysis algorithm to minimize user expertise required for analysis. The resulting PiScanner allows ERS measurements to be performed in about 2 min with complete analysis of the measurements in about 3 min. Two field investigations were performed on a concrete test slab and at an express highway to prove the reliability and feasibility of PiScanner. Vertical variations of elastic modulus of concrete layer were successfully obtained by PiScanner.

Measurements of the Stiffness and Thickness of the Pavement Asphalt Layer Using the Enhanced Resonance Search Method

“…The thickness of the asphalt layer was determined using the ERS method. This method is a combination of the SASW and resonance method, whereby SASW determines the shear wave velocity profile and the thickness of the asphalt is determined using a resonance search [ 5 , 6 ]. Due to the inadequacy of measuring the pavement layer thickness by SASW, a resonance search of the pavement layer is used to ensure that the thickness of the pavement layer is determined accurately.…”

“…An automation algorithm was developed by Joh et al [ 5 ], for which this new algorithm was used to ease vertical profiling of concrete modulus in rigid pavement because conventional computation requires 15 to 30 minutes to compute theoretical modelling of wave propagation. By using this algorithm, approximately 3 to 5 minutes was taken for the analysis time.…”

“…Recently, Joh et al [ 5 ] developed a new tool, known as a pavement integrity scanner (PiScanner), to evaluate the stiffness for pavement layers system and, at the same time, the thickness of the pavement can be identified. In this study, the enhanced resonance search (ERS) method was used to determine the thickness and stiffness of the asphalt surface layer by using PiScanner.…”

Aplicabilidad del método de los elementos finitos en el análisis y dimensionamiento de losas JCPC para carreteras de dos carriles

“…El módulo elástico de la base granular conocido como resiliente se determina por medio de ensayos triaxiales cíclicos Ping et al [8], [9], que para el caso es un valor característico del módulo de reacción de la subrasante y el espesor de base granular empleados. El módulo elástico de las losas de concreto hidráulico se establece a través de ensayos estáticos a carga uniaxial Joh et al [10], [11]. La determinación de los parámetros de diseño de pavimentos rígidos tiene principio en el diseño empirico-mecanístico, que consiste en modelar la estructura a partir de la definición de los espesores y las rigideces (módulos elásticos, reacción y de Poisson) de cada capa para calcular las tensiones y compresiones provocadas por una carga tipo e identificar: a) el máximo esfuerzo principal a tensión en las fibras inferiores o superiores de la losa (σ t ) capaz de producir rotura en las losas; este esfuerzo se compara con el límite admisible del concreto hidráulico (σ tadm ) que es función del tránsito, esfuerzo a tensión aplicado y módulo de rotura, siendo este último parámetro determinado mediante el ensayo de viga de cuatro puntos; b) máximas deformaciones a compresión (ε c ) en las capas granulares y subrasante que se compara con la admisible (ε cadm ) y que depende del nivel de tránsito LCPC [13].…”

Measurements of the elastic modulus of pavement subgrade layers using the SASW and FWD test methods

“…By generating Rayleigh waves over a wide range of frequencies, the shear wave velocity of pavement and ground can be determined (Hazra, Kumar 2014). The SASW method has become a reliable technique to characterize the site and calculate the shear modulus of a layered system, such as layers of soil, asphalt and concrete (Cho 2002;Joh et al 2008;Rosyidi 2004;Rosyidi et al 2012). Previous studies conducted by Röesset et al (1990), Joh (1996, Rosyidi (2004) and Taha et al (2007) show that surface wave method has been utilized to find only modulus for subgrade layer of pavement.…”