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Underground construction and tunnel excavation are known to redistribute stresses and cause ground displacement. Analytical solutions for stress distribution typically break down at shallow depths or in soil masses that exhibit high spatial variability, making numerical simulations necessary. Seeking to find new geometries and excavation strategies for underground construction, we propose to look to nature for inspiration. We extract 3-D digital twins of Florida Harvester ant (Pogonomyrmex Badius) structures from a nest cast in situ and simulate the stress and displacement fields around that nest with the Finite Element Method (FEM). Stress invariants around the main shaft are compared to those around idealized geometric representations of that shaft, i.e. helixes with a fixed pitch angle and a uniform elliptical cross-section. Helical structures made of circular cross-sections and horizontally oriented elliptical cross-sections interact in a way that reduces the risk of tension failure and distributes the shear stress more evenly. One can show that in addition to the extra stability that they offer and the lower risk of tensile or shear failure that they exhibit, helical shafts have the advantage of requiring less power to excavate than straight sub-vertical shafts. 

In Fall of 2024, central Florida was impacted by Hurricane Helene (landfall in Perry, FL as a Cat 4 hurricane on Sept 27) and by Hurricane Milton (landfall in Siesta Key, FL as Cat 3 on Oct 9). The hurricanes led to damages of an estimated value > $200billion. The Nearshore Extreme Events Reconnaissance Association (NEER) and the Geotechnical Extreme Events Reconnaissance Association (GEER) represented by their members from more than 10 academic institutions, federal agencies, and industry and supported by technical staff from the NHERI RAPID facility and the UF Center for Coastal Solutions initiated on Sept 23 a data collection effort that included pre-, during-, and post-storm multi-disciplinary data collections efforts. The field data collection effort was concluded on Nov 22. Data includes hydraulic information on storm surge, waves, and currents, topographic and bathymetric data sets, terrestrial and seabed mapping, and geotechnical site characterization including in-situ testing, sediment sampling, and seismic testing. Data was collected in four focus areas in Florida (Cedar Key; Horseshoe Beach; Midnight Pass and Milton Pass, both near Venice) and observational data and limited data products were collected in other areas in Florida including Orchid, Ponte Vedra, Suwannee, Panama City, and others. Data is organized by site (four primary sites and others); data collection phase with respect to the two hurricanes; and instruments or data collection method. This work included support from both the UF Center for Coastal Solutions and the NHERI RAPID facility. 

This project documents flood-induced geo-structural damage and geomorphological change due to the flooding in the Ahr Valley in Germany during the 2021 Western European floods. It contains detailed, multi-instrument measurements both within the river channel and along the river banks at five carefully selected sites. 

Between July 14–16th, 2021, record rainfall and subsequent flooding resulted in the deaths of over 200 people and billions of dollars-worth of damage in Germany and Belgium. An NSF sponsored Geotechnical Extreme Events Reconnaissance (GEER) Association reconnaissance mission was undertaken by the authors to investigate the effects of flooding in Germany, Belgium, and the Netherlands. The two-week-long mission provided insight to the performance of various geostructures such as building foundations, roads, and bridges. This paper provides a summary of observations made by the US-based GEER team in collaboration with many local European colleagues. Key observations presented include a bridge case study, the impact of scour and erosion on different structures, and soil-structure interactions. A review of the data used to inform the reconnaissance mission as well as the data collection technologies used, including terrestrial LiDAR, UAV-Structure from Motion (SfM), and multispectral imagery, is also presented. 

In June 2022, the southern part of Montana and the northern part of Yellowstone National Park experienced flooding along multiple watersheds, including the Yellowstone River. The flooding resulted from heavy snowmelt between June 10-13th, leading to record levels of river water elevation in most of the main tributaries to the Yellowstone River. Substantial damage occurred to residential, commercial, and transport infrastructure, however, no fatalities were reported. Estimated damages accumulate to approximately U.S. $29 million. The GEER reconnaissance effort, conducted between June 30th – July 4th, recorded geotechnical, geo-structural, and geomorphological observations of failures as well as successful mitigation of flood damage. In addition to traditional terrestrial photography and aerial imagery, the team collected (Light Detection Ranging (LIDAR) scanning, Structure for Motion (SfM) imagery, and Multispectral Imagery to establish point cloud models for case history analyses and post-reconnaissance failure analyses. 

Types of damages: bridge and infrastructure damage, damage to residential buildings, erosion, scour, riverbank failures Methods: photos, description, lidar, drone imagery and structure from motion, multispectral imagery, soil samples and testing