A Project-Based Sustainability Rating Tool for Pavement Maintenance

Pavements require maintenance to prevent undue distress or to restore performance; however, pavement maintenance and its impacts do not receive enough attention in many cases, and are either ignored or treated as a low priority, Most current maintenance activities have budget issues and only focus on removing deteriorated pavement sections, Deferred pavement maintenance has impacts on the environment and on society, and may thus affect the costs associated with maintenance, A sustain- ability rating tool is a good way to list, explain, and evaluate such impacts, Various sustainahility rating tools have been developed for pavement; however, pavement maintenance has its own features that are different from those of the new construction, expansion, or reconstruction of pavements, This research project reviews nine sustainahility rating tools for pavement, although none of these tools fully describe maintenance features or can he directly applied to evaluate maintenance projects, A new sustainahility rating tool is then developed for pavement maintenance; this new tool can he used to evaluate individual projects and raise public awareness about the importance of pavement mainte- nance, Its details are described, and its use is demonstrated through an example to show the evaluation process and results,

Design and laboratory evaluation of fog-sealed chip seal on epoxy asphalt pavement for steel bridge deck

In order to improve the surface performace of epoxy asphalt pavement （EAP） for steel bridge deck, an epoxy asphalt chip seal （ ECS） covered by a cationic emulsified asphalt fog seal （i. e., fog-sealed chip seal） isproposed and a laboratory study is conducted to design and evaluate te fog-sealed chip seal. First, the evaluation indices and methods of te chip seal on steel bridge deck pavement were proposed. Secondly, the worst pavement conditions during te maintenance time were simulated by te small traffic load simulation system MMLS3 and the short-term aging test for minimizing the failure probability of chip seal. Finally, the design parameters of fog-sealed chip seal were determined by the experimental analysis and the performance of the designed fog-sealed chip seal was evaluated in thelaboratory. Results indicate that the proposed simulation method of pavement conditions is effective and the maximal load repetitions on the EAPslab specimen are approximately 925 300 times. Moreover, the designed fog-sealedchip sealcan provide a dense surface with sufficient skid resistance,aggregate-asphalt aahesive performance and interlayer shearing resistance.

Laboratory evaluation of high-friction thin overlays for pavement preservation

Traditional asphalt concrete(AC)and stone matrix asphalt(SMA),which are used as thin asphalt overlays,are common maintenance strategies to enhancing ride quality,skid resistance,and durability.Recently,several studies have used a novel asphalt mixture known as a high-friction thin overlay(HFTO)to improve surface characteristics.However,it remains uncertain whether the laboratory properties of HFTO differ significantly from those of conventional mixtures.This study aims to evaluate the laboratory properties of HFTO mixtures and compare them with those of AC and SMA.Those mixtures with nominal maximum size of 9.5 mm were produced in the laboratory,and performance tests were conducted,including wheel tracking test,low temperature flexural creep test,moisture susceptibility test,Cantabro Abrasion Test,Marshall Test,sand patch test,British pendulum test,and indoor tire-rollingdown test.The results showed that the HFTO exhibited a lower tire/pavement noise than the AC and SMA.Additionally,HFTO had superior high-temperature stability,larger macro texture,and higher skid resistance in comparison to those of AC,but lower than those of SMA.Consequently,HFTO mixtures may be considered a suitable replacement for traditional AC mixtures in regions where skid resistance and noise reduction are concerns.

Preface for the special issue on ＂Maintenance and Rehabilitation of Pavements＂

The International Society for Maintenance and Rehabilitation of Transport Infrastructures （iSMARTi）, the National University of Singapore and the Pavement Engineering Society （Singapore） jointly organized the 8th International Conference on Maintenance and Rehabilitation of Pavements （MAIREPAV- 8） in Singapore on 27-291uly 2016. The conference covered all aspects of maintenance and rehabilitation of road and airport pavements. Over 200 participants from 32 countries participated in this conference, which featured more than 120 technical presentations and two forums.