Structural Health Monitoring in Historical Buildings: A Network Approach

Abstract

Structural health monitoring (SHM) in historical buildings can be achieved through systems that rely on Wireless Sensor Networks (WSNs). Such systems have the ability to acquire information fast and reliably, making them ideal for SHM applications. Historical buildings, having been exposed to the wear of time, are especially sensitive to any kind of intervention. As a result, keeping them as intact as possible is a critical factor for their integrity. In the current work, a low-cost WSN system and a synchronization algorithm are developed in order to be employed for SHM of historical buildings. The synchronization of WSN-based SHM systems is critical for the collection of accurate information describing the building’s condition. The effectiveness of the assumed hardware and the synchronization algorithm were evaluated with two experiments. The first took place under laboratory conditions and its results showcase the algorithm’s accuracy of synchronization. The second experiment was conducted in a real-world environment. For that purpose, the Ionian Campus Testbed was chosen since it comprises buildings that are more than 200 years old. These buildings are appropriate since they were built with thick stone walls which help determine the system’s effectiveness under such conditions. The results derived from the second experiment showcase the effects of the packet transmission collision avoidance mechanism utilized by the assumed hardware. Finally, an estimation of the average clock skew required for accurate information gathering is derived, based on the materials comprising a historical building.