Field Measurements for Estimating Impact Loads on Girder Supports for Ferry Ramps
Abstract
In Port Aransas, TX, movable bridges, ferry ramps, are used to dock ferry boats and load vehicles on and off of the boats to cross the Corpus Christie, TX ship channel as part of State Highway 361. Fatigue cracks are present in several of the bearing assemblies that attach the ramps to the headwall at the ferry landing. The cracks were caused by axial forces in the main supporting beams of the ramps. Using strain gage instrumentation applied to the beams, estimates of the axial forces were obtained. A video camera was installed to allow the research team to distinguish between loading events caused by large or small ferry boats. The recorded data from the instrumentation was accessed remotely from Texas A&M University in College Station and analyzed using MatLAB, Mathematica, and Microsoft Excel. Load data was collected for several months. The information was used to develop recommendations for design loads to be used when the bearing assemblies are rebuilt. Results indicate that the exterior beams of the ramps experience the largest force values in compression caused by docking and thrusting of the ferry boats. The interior beams experience majority of the tension forces caused by vehicles crossing the ramps. To date, the largest force detected is 102.56 kips in compression.
Citation
Lyons, Kimberly (2015). Field Measurements for Estimating Impact Loads on Girder Supports for Ferry Ramps. Master's thesis, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /155100.