Inspection & Maintenance of Cable-Stayed Bridges Piers

For this project BM was tasked with cleaning, inspecting and performing repairs on the piers and the lightning protection system of one of the largest cable-stayed bridges in the world. Afterwards, detailed 3D photogrammetric models of the pylons splash zone and the lighting protection systems where created to capture their as-is condition and aid in future maintenance as an extremely accurate historical point of reference.

Firstly, our team of divers where deployed for the cleaning works. Utilizing high pressure water blasters, rotary brushes and cutting blades, the algea and heavy barnacle buildup where removed. Alongside the divers one of our inspection class ROVs was deployed to monitor the progress of the works, aid in topside-diver communications and enhance the overall mission safety.

Subsequently, the Detailed Visual Inspection (DVI) of both the bridge piers and the lightning protection systems was executed by our ROV team. Despite strong currents exceeding 3 knots, our ROV—equipped with advanced station-keeping sensors and operated by our experienced pilots—was able to maintain stability and maneuver safely. Utilizing its 4K UHD camera, the ROV captured high-resolution images and videos, ensuring a comprehensive and detailed inspection while also collecting the necessary data for the creation of detailed 3D photogrammetric models. This ensured a comprehensive and accurate digital reconstruction of the inspected structures, providing an invaluable resource for future maintenance and analysis.

Following the inspection, the areas requiring repairs were identified, primarily locations where the reinforcement bars had become exposed. Our dive team was then deployed to prepare the affected areas, ensuring optimal adhesion for the repairs. High-strength underwater epoxy was applied to protect and restore the integrity of the structure. Throughout the process, our ROV provided continuous monitoring—not only for safety and topside-diver communication but also to document the repairs, verify proper application, and ensure quality control.

View the 3D photogrammetric models:

Lightning Protection System 3D Model

Pier Cone Wall 3D Model

Interested in how our expertise can benefit your project? Let's discuss how we can support your next challenge!

Our client has created a promotional video showcasing their long-term maintenance efforts. BM is proud to have contributed to this project, providing critical inspection, maintenance and 3D modeling services. Watch the video below!