The use of hot in-place recycling (HIR) for pavement surface rehabilitation has gained increasing attention in recent years with the aim of achieving sustainable pavement. For the purpose of cost saving and the consumption of 100%... more
The use of hot in-place recycling (HIR) for pavement surface rehabilitation has gained increasing attention in recent years with the aim of achieving sustainable pavement. For the purpose of cost saving and the consumption of 100% reclaimed asphalt pavement (RAP), an in-place HIR train has been developed to combine various units including preheating, milling, rejuvenating, and compacting. Compared with the conventional hot-mix asphalt (HMA) surface treatment, the HIR technique might result in different pavement performances as a result of the low mixing temperature and insufficient quality control. This study aimed to conduct a comparative analysis of pavement surface rehabilitation using HIR and HMA, including the performance evaluation, pavement life prediction, and life cycle cost analysis (LCCA). HIR and HMA mixes were collected from construction areas and the nearby asphalt plant, respectively. The loose mixes were reheated and compacted for performance testing, including dynamic modulus tests, Superpave IDT tests, and moisture susceptibility tests. The AASHTOWare Pavement ME Design software was adopted to predict the pavement life with two rehabilitation techniques, followed by the LCCA with regard to the prediction results. Test results showed that pavement surface rehabilitation with HIR achieves acceptable performance and economic benefits. However, the HIR mixes are brittle and more susceptible to cracking and, therefore, have shorter pavement service lives than HMA.
Research Interests:
Precise characterization of the compactability of aggregates and soils in the laboratory has always been a challenge to pavement technologists. The present study investigated compactability of aggregates and soils through the comparison... more
Precise characterization of the compactability of aggregates and soils in the laboratory has always been a challenge to pavement technologists. The present study investigated compactability of aggregates and soils through the comparison of three laboratory compaction methods, the Superpave Gyratory Compactor, the Marshall impacting hammer, and a vibratory compacting machine. Accelerometers were attached to the Marshall impacting hammer and a laboratory scale vibratory compactor to capture the dynamic response of soils and aggregates during compaction. The results from this comparative experiment indicated that there was a consistent relationship between the stiffness of soils and aggregates and the dynamic responses from impaction and vibration, which can be used to better characterize the compactability of different paving materials through laboratory testing.
Research Interests:
Research Interests:
AbstractThis study used a large-scale cyclic shear test to investigate the interaction mechanisms between a geogrid and its surrounding aggregate in a cyclic loading mode to simulate traffic loads....
Research Interests:
Research Interests:
For gyratory compaction, the concept of the locking point was initially developed to identify the compactability of asphalt mixes and to alleviate potential aggregate crushing in the mold. Most previous studies on the locking point were... more
For gyratory compaction, the concept of the locking point was initially developed to identify the compactability of asphalt mixes and to alleviate potential aggregate crushing in the mold. Most previous studies on the locking point were based on specimens’ height change. Recent studies have indicated that the gyratory locking point of cold mix asphalt mixtures could be determined by the rotation angle range indicator using SmartRock. However, height or rotation angle change ultimately reflects a change in volume. Additionally, there is no clear physical and mechanical connection between the volume change and the gyratory locking point. In this paper, a stone mastic asphalt mixture (SMA 13) was selected for gyratory compaction applying various compaction temperatures. The compaction data were recorded by a SmartRock embedded in different positions. Collected data included stress, rotation angle, and acceleration. The major findings are as follows: (1) the specimen’s locking point cou...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
As the concept of sustainable pavement gains prominence, a growing number of industrial wastes and recycled materials have been utilized in the pavement industry to preserve natural resources. This study investigates the potential use of... more
As the concept of sustainable pavement gains prominence, a growing number of industrial wastes and recycled materials have been utilized in the pavement industry to preserve natural resources. This study investigates the potential use of waste glass powder-based geopolymer cement as a stabilizing agent in recycled waste glass aggregate (GA) bases. Two recycled materials, waste glass powder (GP) and class F fly ash (FF), were used as the raw materials in the preparation of geopolymer. Virgin aggregate (VA) was replaced by GA at varying replacement ratios as the pavement base materials, and the mechanical behaviors before and after geopolymer stabilization were evaluated. Without stabilization, the incorporation of over 10% GA caused significant detrimental effects on the California bearing ratios (CBR) of base materials, which should be carefully managed in pavement construction. However, all geopolymer stabilized samples showed decent strength properties, indicating the effectivenes...