| Roadway's infrastructure are the means for connecting people and providing access for mobility. The traffic-induced strains and stresses generated by vehicles can be potentially used for energy harvesting purposes. Piezoelectric devices are ideal candidates for harvesting energy in a pavement structure while they convert mechanical strain energy into electric voltage.;In this study, a comprehensive experimental program was conducted to evaluate the potential of harvesting energy from roadways using piezoelectric transducers embedded within pavement layer structures. Three prototypes were developed in this study. Prototype I is consisting of piezoelectric transducer disks layered between two copper plates was assembled in between asphalt mixture specimens. A uniaxial compression test was performed to measure the output power under different numbers, making up the arrangements of piezoelectric transducers. Moreover, the sensitivity of the power to loading frequency, vertical load, test temperature, and loading time was also studied.;Prototype II was made of a piezoelectric film in order to study energy harvesting using available tensile stresses in the pavement. Flexural fatigue test was performed on the prototype II to produce tensile stress at the bottom of compacted hot mix asphalt beam where the piezoelectric film was attached. Another prototype called III was developed using stack of piezoelectric disk to be tested in Asphalt Pavement Analyzer machine. Besides the laboratory experimental plan, three-dimensional finite element simulations of a single piezoelectric disk under a haversine load, a piezoelectric beam under different loading types, all prototypes under static load, and a large section of pavement, including different pavement layers under static load caused by truck dual-tire was performed using finite element ABAQUS program. A statistical model was developed to predict the output power for the actual tire loads considering traffic variables.;The experiment results show that the quantity and arrangement of the piezoelectric sensors alter the applied stresses leading to variations in the generated output power. The effect of the temperature on the output power was found to be negligible. In addition, the magnitude and loading time significantly affected the output power. Durability tests indicated that the performance of developed energy harvesting systems is not time dependent. Finite element results assisted in finding the concentrated stress on piezoelectric disks, validate the lab results, and find the best location of the energy harvesting modules in the pavement.;All prototypes were compared considering many variables associated with their performance. The prototype I including four piezoelectric disks generated the highest power among all prototypes at a same loading condition. The cost analysis showed that, prototype I can produce an energy up to 860 watt-hour per year. The results suggests that, considering the best prototype, the piezoelectric devices could be ideal candidates for harvesting energy in pavement structures in locations where power grid is not available. The harvested energy can be used to supply power for traffic lightings and sensors imbedded within the pavement. |
