Over the last decade, unexpected and sudden pavement failures have occurred in several provinces in South Korea. Some of these failures remain unexplained, further illustrating the gaps in our knowledge about binder chemistry. To prevent premature pavement distress and enhance road performance, it is imperative to provide an adequate characterization of asphalt. For this purpose, the current re...

This project documents the impact of a porous asphalt overlay on the quality of highway stormwater runoff. A porous asphalt overlay, also known as a permeable friction course (PFC) or open graded friction course (OGFC), is a layer of porous asphalt approximately 50 mm thick which is often applied on top of conventional asphalt highways to enhance safety and reduce noise. The quality of stormwat...

The paper presents results of sensitivity analysis to crack propagation of a pavement bituminous layered structure using the Finite Element Method (FEM) and Artificial Neural Networks (ANN). The performed preliminary study determined stresses and displacements in the pavement layer system. The pavement structure consisting of asphalt layers, a base layer, subbase and subgrade layers was analyze...

Asphalt is a visco-elastic material having properties of elastic solid at low temperature and viscous liquid at high temperature. Properties of asphalt binder depend upon temperature, rate of loading and aging conditions. Although asphalt binder is only 4-5 % of asphalt concrete mix by weight but it plays a vital role in defining the pavement performance. That is, pavement response is heavily d...

This study examines the effectiveness of HMA overlay design strategies for the purpose of controlling the development of reflective cracking. A parametric study was conducted using a 3D Finite Element (FE) model of a rigid pavement section including Linear Viscoelastic (LVE) material properties for the Hot Mix Asphalt (HMA) overlay and non-uniform tire-pavement contact stresses. Several asphalt...

Asphalt pavement recycling has grown dramatically over the last few years as the preferred way to rehabilitate existing asphalt pavements. Rehabilitation of existing asphalt pavements has employed different techniques; one of them, cold in-place recycling with foamed asphalt (CIR-foam), has been effectively applied in Iowa. However, Iowa’s current cold in-place recycling (CIR) practice utilizes...

Roadways are considered one of the most important elements of infrastructure and they play an essential role in our daily lives. In road pavement construction, the use of crumb rubber in the modification of bitumen binder is considered as a smart solution for sustainable development by reusing waste materials. It is believed that crumb rubber modifier (CRM) could be one of the alternative polym...

Permeability of an asphalt pavement is one of the most important parameters that have a direct influence on its design life. It is an intrinsic property that relates the average fluid velocity to a constant pressure gradient; however, the external pressures on a saturated pavement pore structure are often dynamic due to the repeated tire loading in the field. A dynamic permeability constant, th...

asphalt modification/reinforcement has received considerable attention as viable solutions to enhance flexible pavement performance. this is mainly prompted by the unsatisfactory performance of traditional road materials exposed to dramatic increases and changes in traffic patterns. this paper presents the evaluation of fatigue behaviour of nano reinforced stone mastic asphalt mixtures. fatigue...

We present a ground penetrating radar (GPR) system, which uses an antenna array for in situ measurements of the thickness and dielectric permittivity of an asphalt pavement layer. We calibrated the antenna array by considering the antenna phase center and the antenna offset. The results of the laboratory measurements demonstrate that the proposed calibration method can greatly improve the accur...