Real-time monitoring of strain and modulus of asphalt pavement using built-in strain sensor cluster

Abstract

Pavement health monitoring is helpful to understand the structural state of interlayer and make reasonable maintenance decisions. This study aims to propose a real-time strain and modulus monitoring method using built-in strain sensor cluster. First, the four-point bending beam test was conducted to demonstrate the possible poor deformation compatibility between a single built-in strain sensor with asphalt mixture under different temperature. Then, the potential mapping relationship between the output of the built-in strain sensor and the real strain of the matrix material was explored by mechanical derivation. Subsequently, the real-time strain and modulus monitoring method based on built-in strain sensor cluster was discussed and proposed. Finally, a three-dimensional finite element model was developed to validate the applicability of the proposed method to the dynamic response monitoring of elastic and viscoelastic pavement systems. The results indicate that the difference in modulus between the built-in strain sensor and the asphalt mixture causes the sensor output to deviate from the true value. The modulus ratio and strain ratio between the built-in strain sensor and the asphalt mixture satisfy the mapping relationship. The monitoring method based on the built-in strain sensor cluster can overcome the strain measurement errors caused by the poor deformation compatibility and also enables real-time monitoring of pavement modulus. In general, this work provides a new framework for real-time evaluation of strain and modulus in pavement health monitoring.