Optimum Base Connection of Columns in Steel Gable Frames

Naser Katanbafnezhad, Alan Hoback

International Refereed Journal of Engineering and Science (IRJES), vol. 9(3), 2020, pp. 49-58.


Optimum base connections were found for steel gable or portal frames with different roof slope. Five locations, Detroit MI, Miami FL, Santa Barbara CA, St. Paul MN and Berlin NH, were chosen because they represented a variety of loading conditions. Multiple structures were designed for each location with span to height ratios from 1 to 10, and varying roof angles. Analysis was done for each case using ETABS. This provided patterns in stress efficiencies that the helped identify possible optimum base connection. Precise designs with the LRFD method were performed on both pin and fixed base connection for each span length in its optimum roof slope. It was found that for all locations and all geometries fixed base connection saves weight. The average savings was 20%. Primary factors in determining base connection in these situations were magnitude of loads and length of span.

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