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Bridge Diagnostics was contracted by the U.S. Army Corps of Engineers to perform live-load testing and load rating on Bridge FSBR-514 on Walker Road over Kahauiki Stream, Fort Shafter, Hawaii, in conjunction with three other structures - Bridge FSBR-201, FSBR-1608, and ERBR-9. A primary goal of the live-load testing was to determine the relative effects of different military load configurations. A second goal was to use the measured load responses to verify and calibrate a finite element model of the structure. The load test results indicated that the culvert was relatively stiff and did a good job of distributing load. Load ratings resulting from the field-verified model indicated that all examined load configurations could cross the bridge within inventory (design) limits. Load ratings were computed in accordance with the American Association of State Highway and Transportation Officials' AASHTO LRFD bridge design specifications (2004) and Manual for the condition evaluation and load and resistance factor rating of highway bridges (2003)., The original document contains color images.

In June 2007, Bridge Diagnostics, Inc. (BDI), was contracted by the U.S. Army Corps of Engineers to perform live-load testing and load rating on Bridge S-4360 at Camp Hovey, South Korea, in conjunction with two other structures, S-1801 and S-1090 at Camp Casey. A primary goal of the live-load testing was to determine the relative effects of different military load configurations. Of particular interest was determining the benefit of using the Heavy Equipment Transporter System (HETS) to transport heavy equipment such as an M1A1 tank. Another goal was to use the measured load responses to verify and calibrate a finite element model of the structure. The model resulting from the structural identification procedure was then used to generate accurate load ratings for specific AASHTO (American Association of State Highway and Transportation Officials) and military load configurations. Both the direct load test and subsequent load rating results indicated that the M1A1 tank generated greater flexural stresses than did the HETS carrying the M1A1 tank. The bridge appeared to be in good condition and was apparently designed to carry heavy military loads. Load rating calculations determined that all vehicles considered could cross the bridge within Inventory (normal design) stress limits., Prepared in collaboration with the Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, MS and the Eighth U.S. Army, Seoul, South Korea. The original document contains color images.

In June 2007, Bridge Diagnostics, Inc. (BDI), was contracted by the U.S. Army Corps of Engineers to perform live-load testing and load rating on Bridge S-1090 at Camp Casey, South Korea, in conjunction with two other structures, S-4360 and S-1801. The general goal of the live-load testing was to obtain and then utilize field measurements to verify an analytical model from which accurate load ratings could be obtained. A more specific purpose of the load test was to determine if the use of the Heavy Equipment Transporter System (HETS) to transport an M1A1 tank across the bridge was more or less severe than the M1A1 tank crossing on its own. Controlled load tests were performed with a three-axle dump truck, an empty HETS, an M1A1 tank, and a HETS carrying an M1A1 tank. The load test data were examined to obtain a direct comparison of load responses from the different load configurations. The conclusion obtained directly from the load test data was that the HETS/M1A1 load combination produced lower stresses than the M1A1 tank by itself. Subsequent modeling and analysis of the bridge further verified that the HETS was the best option for transporting the M1A1 across the bridge. Load ratings were performed for the standard American Association of State Highway and Transportation Officials (AASHTO) vehicles and several military load configurations in accordance with AASHTO Load and Resistance Factor Design Bridge Design Specifications 2004 and Manual for Condition Evaluation and Load and Resistance Factor Rating of Highway Bridges 2003. It was found that the structure can safely carry all of the AASHTO vehicles and military load configurations considered in this report., The original document contains color images.

This study focuses on the load rating analysis of a prestressed concrete channel-beam located at the Naval Weapons Facility in Charleston, SC, subjected to military moving loads through load testing and analytical models. The superstructure of the bridge was instrumented with 56 reusable strain transducers to accurately characterize the structure's live load response. A load test was initially performed with a 67-kip dump truck across the bridge along three lateral paths. The load test results were used to calibrate a finite element model in order to verify if the structure could safely handle larger loads imposed by the heavy equipment transporter system carrying an MIA1 Abrams tank and the Rough Terrain Container Handler DV43 handler vehicles. Once it was confirmed by the model that these larger vehicles could cross controlled load tests were performed with both vehicles, and data were recorded during multiple passes of both vehicles. These data were used to verify the predicted responses and to verify that the loads were not inducing damage to the structure. When the testing phase was completed, the data were examined thoroughly and the model was revised to best represent the actual structural responses. Load ratings were computed for the standard design and rating vehicles along with several heavy military loads. The main conclusions obtained from the load ratings are that all of the design vehicles and military vehicles can cross the bridge within the Operating (maximum) load limits. All of the vehicles, with the exception of the four-wheeled cargo handlers, can cross the bridge within the Inventory (design) load limits. Two of the most important parameters that can be determined when a load testing analysis is performed are the dynamic allowance (impact factor) and the live load distribution., The original document contains color images.