29 May 2024

Performance of Army Corps of Engineers Mat System Using Anchorless Connections: A Follow-on Study of Site Stabilization for the Improved Ribbon Bridge Bridge Supplemental Set

Abstract: The US Army Engineer Research and Development Center conducted testing of the Army Corps of Engineers mat system with improved anchorage and connection hardware. Low-profile screw anchors replaced the ground anchorage of the existing system to reduce wear to tracks and wheels of vehicles while trafficking the system. Anchorless connections allowed the system to be placed over soils where the use of screw anchorage would be obstructed or would cause hazards to trafficking vehicles. Test tracks were constructed to evaluate the matting system with new anchorage and connection hardware over three different soils of weak sand and clay. Channelized traffic was applied to the test tracks using a loaded common bridge transporter. Performance of the updated system was evaluated with respect to results from previous testing, indicating that the improved anchorage and connection hardware increased the versatility of the matting system without sacrificing system performance.

25 Jul 2023

Bridge Resource Inventory Database for Gap Emplacement Selection (BRIDGES)

Abstract: Wet gap crossings are one of the most complex maneuvers undertaken by military engineers, who, along with engineer planners, require better tools to increase the capacity for efficient use of limited bridging resources across the battlespace. Planning for bridging maneuvers often involves a complicated and inefficient system of ad hoc spreadsheets combined with an overreliance on the personal experience and training of subject matter experts (SMEs). Bridge Resource Inventory Database for Gap Emplacement Selection (BRIDGES) uses interactive mapping and database technology in order to streamline the bridging planning process and provide answers to question about myriad scenarios to maximize efficiency and provide better means of data persistence across time and data sharing across operational or planning units.

25 Jun 2020

PUBLICATION NOTICE: Improved Ribbon Bridge Structural Response Validation Testing

Abstract: vehicles and trucks up to Military Load Capacity 96. The Bridge Supplemental Set (BSS) includes Bridge Erection Boats and an anchorage system to allow for the positioning and securing of the bridge in moving water. Designed to function as either a floating bridge or a raft, the IRB and BSS give military commanders multiple options with regards to the tactical river crossings. The US Army Engineer Research and Development Center (ERDC) was contracted by Product Manager Bridging to provide a structural analysis via high-fidelity numerical modeling of various IRB spans and water flow rates. To this end, a finite element model (FEM) of the IRB was constructed using field measurements of IRB interior bays. To ensure accurate structural response characteristics of the FEM and to build confidence in the simulation results, a validation test series was devised to generate empirical data to correlate against. This report documents the IRB structural response validation testing conducted at ERDC in March 2018. The data contained in this report was used to validate the IRB structural FEM.

25 Jun 2020

PUBLICATION NOTICE: Structural Analysis of an Improved Ribbon Bridge Subjected to Hydrodynamic and Vehicular Loading

Abstract: Structural modeling and simulations were performed to determine limit states of an Improved Ribbon Bridge (IRB) subjected to hydraulic and vehicle loadings. Measurements of as-built IRB bays were used to construct a three-dimensional, computer-aided design model. The model was used to create a computational finite element model (FEM) that was validated through correlations of simulation results and empirical data. The validated FEM was used to establish limit states (i.e., maximum current and vehicular loading conditions for 110 and 210 m IRB crossings). Analyses revealed that the primary structural failure mode was yielding in the steel pins that link IRB bays. Assuming the IRB is adequately restrained at the shores, a 110 m IRB can withstand currents up to 11 ft/s with no vehicle traffic; a 210 m IRB can endure up to 7 ft/s under the same conditions. For risk crossings, one Military Load Classification-70 vehicle on the bridge, 110 and 210 m IRBs can tolerate currents up to 9 and 7 ft/s, respectively. Under normal crossing conditions vehicle spaced 100 ft apart, a 110 m IRB has the structural capacity to endure currents up to 9 ft/s; the maximum current for a 210 m IRB is 5 ft/s.