AI-assisted algorithms assess laser scans of building sites…

05 Jun 2025

…while lidar-based 3D flood visualizations more clearly highlight rising water risks.

Researchers at Oak Ridge National Laboratory, Tennessee, have developed a tool that gives builders a quick way to measure, correct and certify level foundations. FLAT, or the Flat and Level Analysis Tool, examines a 360-degree laser scan of a construction site using ORNL-developed segmentation algorithms and machine learning to locate uneven areas on a concrete slab, for example.

Buildings begin with the pouring of concrete to create a foundation. Deviations not caught before concrete hardens can add hours to construction time and unanticipated costs. The manual method for determining levelness is time-consuming and requires builders to mark the slab with lines and walk it with a profiling tool to collect data.

“With this digital tool, you can quickly get estimates for the foundation’s smoothness with minimal human involvement,” ORNL’s Nolan Hayes said. “This enables faster building construction because FLAT can tell you within a minute if any mistakes were made and where they are.”

Hayes said demonstrations at two housing developments proved FLAT reduced foundation measurement time by more than 90% and required no preparation of the slabs. Future work includes conducting demonstrations with different types of construction including suspended slabs, floor decking and pier foundations.

Lidar-based 3D flood visualization

As climate change intensifies extreme weather, two new studies at New York University show 3D flood visualizations developed by a cross-institutional research team using lidar scans significantly outperform traditional maps for communicating risk. NYU reports that when residents of Sunset Park, Brooklyn, New York, compared both formats that visualized flooding, 92% preferred the “dynamic 3D approach”.

“The challenge we face is that substantial sectors of the population ignore flood warnings and fail to evacuate,” said Prof. Debra F. Laefer, the NYU Tandon School of Engineering senior researcher involved in both studies who holds appointments in the university’s Civil and Urban Engineering Department and in the Center for Urban Science + Progress (CUSP). “Our findings suggest dynamic 3D visualizations could significantly improve how we communicate these life-threatening risks.”

‘More authoritative visualization’

A Laefer-led team from NYU Tandon and NYU Steinhardt School of Culture, Education, and Human Development — with colleagues from University College Dublin and Queen’s University Belfast — has developed a low-cost visualization method that transforms lidar scans of urban streets into immersive flood simulations.

The work is detailed in a paper in Remote Sensing.The team evaluated these visualizations in a second paper, published in Progress in Disaster Science. This study compared visualization methods for a Category 3 hurricane scenario: a conventional NOAA flood map versus a 3D simulation showing water rising to three feet at the intersection of 4th Avenue and 36th in Sunset Park, in Brooklyn, New York.

Not only did participants overwhelmingly prefer the 3D visualization, but 100% of them found it more authoritative than the traditional map, with a significantly better understanding of evacuation challenges.

“We achieved this [result] using a Potree viewer coupled with Inkscape to create dynamic flood water flow,” said Laefer. “Our study did not require a graphics card — just a single, quad-core processor.”

The visualization includes realistic water movement created through compounding sine wave functions, with algorithms controlling transparency, color, and flow speed. “One of the most rewarding aspects was seeing how participants instantly grasped the flood severity without technical explanations,” said Kshitij Chandna, a master’s student advised by Laefer at the time of the research, who is the co-author on both studies. “When someone looks at a 3D simulation and says I would need to evacuate, you know you have successfully communicated risk in a way traditional maps cannot.”

The implications extend beyond flood visualization. The researchers have already demonstrated visualizing water flowing through pipes and are exploring applications for other types of flooding. Their report states, “As climate change increases flooding frequency, this research suggests dynamic 3D visualization could bridge the gap between abstract warnings and concrete actions needed to save lives.”