A New Methodology for Bridge Inspections in Linear Infrastructures from Optical Images and HD Videos Obtained by UAV

Abstract

Many bridges and other structures worldwide present a lack of maintenance or a need for rehabilitation. The first step in the rehabilitation process is to perform a bridge inspection to know the bridge′s current state. Routine bridge inspections are usually based only on visual recognition. In this paper, a methodology for bridge inspections in communication routes using images acquired by unmanned aerial vehicle (UAV) flights is proposed. This provides access to the upper parts of the structure safely and without traffic disruptions. Then, a standardized and systematized novel image acquisition protocol is applied for data acquisition. Afterwards, the images are studied by civil engineers for damage identification and description. Then, specific structural inspection forms are completed using the acquired information. Recommendations about the need of new and more detailed inspections should be included at this stage when needed. The suggested methodology was tested on two railway bridges in France. Image acquisition of these structures was performed using an UAV for its ability to provide an expert assessment of the damage level. The main advantage of this method is that it makes it possible to safely accurately identify diverse damages in structures without the need for a specialised engineer to go to the site. Moreover, the videos can be watched by as many engineers as needed with no personal movement. The main objective of this work is to describe the systematized methodology for the development of bridge inspection tasks using a UAV system. According to this proposal, the in situ inspection by a specialised engineer is replaced by images and videos obtained from an UAV flight by a trained flight operator. To this aim, a systematized image/videos acquisition method is defined for the study of the morphology and typology of the structural elements of the inspected bridges. Additionally, specific inspection forms are proposed for every type of structural element. The recorded information will allow structural engineers to perform a postanalysis of the damage affecting the bridges and to evaluate the subsequent recommendations.

Systematic Literature Review of Drone Utility in Railway Condition Monitoring

“…Rail bridge monitoring: Drones can securely access the upper parts of bridges without interrupting traffic flows. Cano et al (2022) used drones to collect images of two railway bridges in Spain and structural engineers identified defects from those images (Cano, Pastor, Tomás, Riquelme, & Asensio, 2022). Narazaki et al (2022) used drones for a post-earthquake inspection of reinforced concrete railway bridges and localized critical structural elements (Narazaki, Hoskere, Chowdhary, & Spencer, 2022).…”

“…Weather presents another challenge for drone-based RIM (Cano, Pastor, Tomás, Riquelme, & Asensio, 2022). Drones are sensitive to windy and icing conditions (Jarrett, Perry, & Stol, 2015).…”

An Overview of Current Challenges and Emerging Technologies to Facilitate Increased Energy Efficiency, Safety, and Sustainability of Railway Transport

“…Another crucial aspect of railway transportation system resilience is the comprehensive inspection, surveillance, and supervision of critical railway infrastructure, such as tracks [192,194]; overhead power supply lines [192]; power stations, communication, and signalling equipment [214]; and tunnels [179], bridges, and viaducts [215]. To that end, reference [196] illustrates how the use of numerous inexpensive narrow-band remote sensors can improve railway transportation safety in the presence of varying tractions due to the variability of atmospheric conditions (cf.…”

“…also Figure 7). To automate the surveillance and inspection processes, novel image acquisition methods using LIDAR-based photogrammetry are commonly used [187,216] along with high-definition (HD) video cameras [215] and thermal imaging using forward-looking infrared (FLIR) cameras (Figure 16a). These are increasingly being mounted on UAV-based platforms to scan the terrain, buildings, and other parts of railway infrastructure [217], as illustrated in Figure 16b.…”

Task-Driven Path Planning for Unmanned Aerial Vehicle-Based Bridge Inspection in Wind Fields

“…In recent years, the use of UAVs for non-destructive analysis has gained popularity due to enhanced accessibility, cost efficiency, avoidance of traffic disruptions, and reduced safety hazards [4]. Notably, studies by Jeong et al [5], Peng et al [3], Jung et al [6], Cano et al [7], Mohammadi et al [8], and Lee et al [9] demonstrate the effectiveness of UAVs The impact of wind on bridge structures is primarily concentrated on the bridge columns, making them a crucial highlighted focus of UAV monitoring. Establishing bridge models for subsequent numerical analysis proves to be a conveniently feasible approach.…”