Abstract Summary
Deterioration of bridge infrastructure is a serious concern to transport and government agencies as it declines serviceability and reliability of bridges and jeopardizes public safety. Bridge infrastructure, in addition to serving the crucial function of connecting highways, is the most vulnerable constituent of the transportation system. This is often attributed to their exposure to harsh environmental settings as well as heavy loads and traffic volumes that bridges need to sustain. Maintenance and rehabilitation need of bridge infrastructure are periodically monitored and assessed, typically, every two years. Traditional or existing inspection techniques, namely visual inspection, have multiple disadvantages such as subjective, time-consuming, and often incomplete. These are laborious and associated with incomplete assessment due to poor accessibility to critical segments of the bridge, cause traffic disruption, and entail subjectivity in evaluation, among others. Sometimes initial inspections find conditions that warrant repeat inspection and hence, repeated periodic visits to the bridge to check on the progression of initial deficiencies, such as cracks or corrosion. This process is time consuming and costly, especially where inspections must be carried out beneath the bridge deck, i.e., where special equipment with a boom would need to be obtained so as to gain visual access for inspection. Moreover, portions of the bridge superstructure are often located at heights that are difficult to reach and potentially hazardous for bridge inspectors to go. Furthermore, often hundreds or thousands of photographs and instrument readings must be scanned and analyzed by bridge inspectors for indications of potential problems that may warrant further analysis. Studies have identified these limitations and explored innovative and promising bridge inspection technologies to tackle these challenges. These emerging technologies include Non-Destructive or Non-contact methods such as ground penetrating radars, photogrammetry, laser scanning technology, infrared thermography, sensors, machine vision, and unmanned aerial vehicles (UAVs). Non-destructive testing (NDT) using Unmanned Aerial Vehicles (UAVs) have been gaining momentum for bridge monitoring in the recent years, particularly due to enhanced accessibility and cost efficiency, deterrence of traffic closure, and improved safety during inspection. They are often deployed in instances where the infrastructure has limited accessibility, characterized by their height and/or location. This study assess unmanned aerial vehicles (UAVs) that are best suited for inspecting damage in structures and pairing them with a damage detection technique that best suits structural health monitoring of a bridge structure. Upon selection of a UAV and detection method, the technique will be put to the test on bridge prototype in a laboratory. This technique will be compared to the various techniques in literature; for which, if successful, future work will include applying the technique to a real bridge structure.
