This paper presents a 2-year review and an evaluation of the performance of fiber-reinforced polymer-modified asphalt concrete (FPMAC). A comparison is made of its characteristics with polymer-modified asphalt concrete (PMAC) through laboratory experiments and field observations. Polymers are believed to enhance the binding properties of the asphalt pavements to increase their engineering properties. Some researchers and highway agencies in the cold regions have considered adding fibers in the currently used polymer-modified asphalt concrete to produce FPMAC to be used in pavement construction. FPMAC has the potential to enhance asphalt pavement properties, such as increasing stiffness, resistance to deformation, and stability. An asphalt paving project made of PMAC and FPMAC was implemented in Flagstaff, Arizona, with a goal of evaluating the effect of fiber reinforcement in the performance enhancement of FPMAC. FPMAC and PMAC samples were collected at the job site and shipped back to the materials laboratories at both Northern Arizona University and Arizona State University for experimentations. Throughout the thermal cracking tests and dynamic modulus tests, all data indicated that FPMAC has better performance. After 2-year field visits, FPMAC has showed fewer cracks (with accumulative crack length of 11.2 ft) as compared with PMAC (with accumulative crack length of 123.2 ft). FPMAC has successfully demonstrated its abilities to resist thermal cracking, freeze–thaw cycling, and rutting deformation.

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Abstract. This paper presents a data collecting process using smartphonebased accelerometer in association with geographic information systems (GIS) software to better manage pavement condition data and facilitate with decision making for maintenance and rehabilitation. The smartphone is equipped with an accelerometer (a mobile apps) could record 50 vibration data points per second in three direction (X, Y, and Z). The type of Traditional pavement survey is time-consuming and requires experienced technicians to travel along highway to visualize pavement conditions and record any failures. Combining vibration intensity data with a GIS platform can help public agencies with a strategic plan to prioritize maintenance schedules for both bike trails and highway roads. The objective of this paper is to (1) discuss the processes of vibration data analysis using a smartphone based accelerometer and to (2) demonstrate how to relate vibration intensity data to locate priority areas for immediate.Keywords: Vibration Á Smartphones Á Mobile apps Á Accelerometers Á Geographic information systems Background and Problem StatementPavement condition surveys involve data acquisition, interpretation, and documentation. These activities characterize surface condition, such as surface cracking, deformation, and other surface defects for both flexible and rigid pavements. Currently, there are three key major pavement distress detecting techniques; (1) manual inspection, (2) imaging process detection, and (3) vibration-based detection. Manual inspection perhaps is most popular and affordable method among highway agencies for pavement condition surveys. However, manual inspection remains labor intensive and time consuming procedure. It is subject to personal experience and bias, making the survey

Abstract. Using recycled glass in concrete applications decreases the amount of glass in landfills and substitutes for expensive aggregates in the concrete mix. However, there has been a concern on recycled glass with smooth surfaces that would result in a drop in strength and in particular a reduction of an already low ductility. Thus, in many design aspects, the use of recycled glass in concrete is limited up to 30% by weight due to concern on concrete strength reduction. The current manufacturing technology in the recycling glass has been grown and evolved through which recycled glass has been processed to exhibit the following features: basically zero water absorption, excellent hardness (great abrasion resistance), high durability to resist extreme weather conditions, etc. The paper challenges the currently used recycled glass mixtures and presents new mix design principles for concrete mixed with 10%, 20%, 30%, 50%, and 100% recycled glass as replacements of nature sand and Portland cement to assess (1) strength changes and (2) resistance to alkali silica reaction (ASR). Aggregate, water reducer, hydration stabilizer, mid-range water reducer, fiber, and viscosity modifier were prepared with varying dosages of recycled glass. A series of scanning electron microscope (SEM) imaging were performed to evaluate the resistance of recycled glass specimens to ASR. The paper concludes that the use of recycled glass as an alternative aggregate and cement binder in the concrete mixtures show promising performance in both tensile splitting strength and ASR.

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