Model Tests of Steel Tunnel Supports

摘要

In connection with a study of the structural behavior of a diversion tunnel under construction at a U. S. Army Corps of Engineers project, four small-scale model steel tunnel supports were constructed and tested in order to determine how certain details of the footings of the prototype supports affected behavior. Measurements also were made of strains on the innermost and outermost fibers at several points around the circumference of each model. Dial gages at several locations measured deflections. The report presents the results of the strain and deflection measurements in tabulated and graphical form, giving moments and thrusts calculated from the measured strains. In addition, moments and thrusts were computed through use of a popular design method. Comparison of measured values with computed values of moment and thrust indicates needed modification; the design procedure will give erroneous results for ring beams subjected to concentrated loads. (Author)