Extended Abstract: Innovative technologies for the digital transformation in bridge inspection

Routine inspections of engineering structures such as bridges are essential to guarantee their reliability and structural integrity. Many of the tasks involved with bridge inspection use a lot of manual labor and analogue tools. The digitalization of these tasks moving toward more innovative technologies such as Augmented Reality (AR) can be utilized to aid with the inspection process. Most suitable is the use of AR glasses which use stereographic projection to superimpose additional information onto the investigated structures. The main advantage of using AR glasses as compared to AR tablet applications is the ability for the inspector to use both hands freely during the inspection process. The digitalization of these processes intrinsically bares the possibility to interact with a rich variety of building information on-site. A natural fit to organize and maintain these data is to link them with BIM models (BIM: Building Information Modeling). Within BIM models, buildings are segmented into components with varying levels of detail which can be attributed to information such as construction plans, material parameters, former inspection results and more. Beyond the visualization of additional information, the interaction with and annotation of them is possible. This can be done by superimposing the model with the real structures. The ultimate goal is to implement a bidirectional communication interface, such that information can be accessed on-site, but also new inspection results can be linked to the model and uploaded after inspection. As one step towards a digital twin this would assist the inspection process and make it more time efficient. A promising perspective is the use of AR to visualize results of non-destructive testing (NDT) on-site under real-world conditions. One example is the positioning of radar data at the location of measurement, either in combination with the respective BIM model or simply with relative localization. This example can help with localizing and assessing steel rebars. With an according compute power of the AR equipment it is also possible to further process, refine or analyze data on-site, using various numerical methods. This idea holds for any NDT method or also monitoring data, but is especially useful for methods generating visual two- or three-dimensional results. Instead of reviewing NDT data in an office environment, inspectors can have a virtual view into the investigated structure. Another advantage of this process is the easy access to historicized data, allowing the comparison between former inspection cycles. As an example, the time evolution of annotated or segmented cracks, spallings or corrosion spots can be assessed on-site more easily. At the Federal Highway Research Institute we investigate the potential of such applications and how they can support a more efficient and reliable bridge inspection in the field.