Road Piezoelectric Power Output Model and Experimental Study under Bidirectional Vehicle Load Excitation

Abstract

Recently, piezoelectric transducers have gained significant attention for energy recovery applications in road engineering. However, in laboratory tests, vehicle loads are often simplified using vertical vibration loads, thus ignoring the role of vehicle tangential loads. In this study, a power output model of a piezoelectric transducer under vertical and tangential loads was proposed through theoretical analysis. A bidirectional cyclic dynamic load test was conducted on the piezoelectric-concrete specimens in combination with a large dynamic and static straight shear instrument, and the power output law of the piezoelectric transducer under vertical and horizontal shear was investigated. The results revealed that the vertical vibration load was the main factor affecting the output performance of the piezoelectric transducer; however, with the addition of the tangential load, the electric energy output of piezoelectric pavement increased with an increase in the horizontal shear rate and displacement. When vibrating vertically (200 kPa and 4 Hz), the electric energy output of piezoelectric pavement was 4.979  μW. However, under the action of vertical vibration and horizontal shear with the working conditions of 200 kPa and 4 Hz, and 0.1 mm and 1 Hz, the electric energy output of piezoelectric pavement was 21.04  μW, which was 3.2 times that of the vertical vibration load alone. Therefore, by considering the influence of vehicle tangential loads, the power output of piezoelectric transducers can be calculated more accurately, which provides a reference for actual installed capacities in real engineering applications.