Health monitoring of civil infrastructure systems-the stress wave approach

This paper describes the challenges for the health monitoring of civil infrastructure systems and provides an overview of the state-of-the-art of currently available nondestructive evaluation (NDE) techniques based on the principle of stress wave propagation. An introduction to the health monitoring of civil infrastructures is given first. Two main categories of current NDE techniques are presented, including the linear NDE methods and nonlinear NDE methods. Three representative techniques in each category are introduced in detail. Limitations of current techniques are discussed and the future direction for the health monitoring of civil infrastructure systems, in terms of several promising NDE techniques, is described finally.