The detrimental effects of hardening in asphalt pavements were first recognized by pioneering pavement engineers in the 1900s and have been studied extensively during the last 70 years. This hardening process, referred to as asphalt aging, is generally defined as change in the rheological properties of asphalt binders/mixtures due to changes in chemical composition during construction and its service life period. Aging causes the asphalt material to stiffen and embrittle, which affects the durability and leads to a high potential for cracking. This paper presents the state of the art on asphalt and asphalt mixture aging and use of antioxidant additives to retard the aging. A picture of complex molecular structure of asphalt and its changes due to atmospheric condition and various protocols used to simulate aging in laboratory environment are also discussed. Emphasis is given on recent studies on simulation of aging of asphalt mixtures as there has been limited research on mixtures compared to the asphalt binder. Finally, this paper presents the application of antiaging techniques and its mechanism, use of various types of antioxidant additives to retard aging of asphalt and, hence, improve the performance of asphalt pavements.

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State of the Art Study on Aging of Asphalt Mixtures and Use of Antioxidant Additives

Sustainable asphalt concrete containing high reclaimed asphalt pavements and recycling agents: Performance assessment, cost analysis, and environmental impact

Evaluation of thermal conductivity of asphalt concrete with heterogeneous microstructure

Pavement temperature prediction: Theoretical models and critical affecting factors

Identifying new energy saving methods in the building sector is essential due to limited natural energy sources and the rising population. Thermal mass materials have the ability to absorb and store heat before releasing it later on when necessary. They act as heat sinks during the daytime and as heat sources during the nighttime. Thermal performance is evaluated according to the specific heat capacity and specific latent heat. Applying thermal mass materials such as concrete is deemed a suitable strategy to reduce the energy consumption of buildings. Concrete with low thermal conductivity and high specific heat capacity is desirable in building construction. The aim of this study is to review factors affecting the heat storage capacity of concrete. In addition, common measurement methods of cement-based materials’ thermal conductivity, thermal diffusivity and specific heat capacity are reviewed. Various studies reveal that temperature, humidity, aggregate type, cementitious material type as well as phase change material (PCM) used influence the thermal properties of concrete. The advantages and limitations of PCM-concrete are also summarized in this study.

Concrete as a thermal mass material for building applications - A review

Effects of recycled asphalt pavements on the fatigue life of asphalt under different strain levels and loading frequencies

A study of asphalt aging using Indirect Tensile Strength test

Determining thermal properties of asphalt concrete using field data and laboratory testing

The research reported in this paper investigates the coefficient of thermal contraction (CTE) and coefficient of thermal expansion (CTE) of asphalt concrete (AC) under different conditions in the laboratory. As a first step, the CTC and the CTE of AC at different temperatures ranging between −20 and 55°C were measured using field samples to examine the temperature effect. Then, the difference in the CTC and the CTE values in the vertical and horizontal directions (cross anisotropy) were evaluated using field samples. The influences of air void (AV), aggregate type, and aggregate gradation on the CTC and the CTE values were also investigated using laboratory prepared SuperPave gyratory samples. The deformation measuring devices, LVDTs, were calibrated using a zerodur to eliminate the temperature effect on the LVDTs. Results show that the CTC and the CTE values of AC are nonlinear with temperature and vary with aggregate type. However, gradation of aggregate and AV of sample do not affect the CTC an...

Rashadul Islam

Papers

Effects of recycled asphalt pavements on the fatigue life of asphalt under different strain levels and loading frequencies

A study of asphalt aging using Indirect Tensile Strength test

Determining thermal properties of asphalt concrete using field data and laboratory testing

Coefficients of Thermal Contraction and Expansion of Asphalt Concrete in the Laboratory

Determining temperature and time dependent Poisson’s ratio of asphalt concrete using indirect tension test