AN EXPERIMENTAL STUDY OF A TRANSVERSELY STIFFENED TAPERED BOX GIRDER UNDER TORSION AND BENDING
Abstract
The strain distribution in a moderately tapered (10%), transversely stiffened, thin-walled Duralumin box was tested under torsion and/or bending. Direct and shear-strain distributions were measured around representative cross sections with electric resistance strain gages. Comparisons of the test data with theoretical analyses indicated that: (1) maximum direct strains at the root (under shear loads) exceed conventional beam-theory predictions by as much as 20%; and (2) the maximum shear strain immediately inboard of the innermost loading section (under torque) exceeds the theoretical predictions by 34%. Analyses are included which treat the box as (1) an equivalent 4-boom tube and (2) a tube with direct stress-carrying covers. Both gave equally good estimates of the torsional-load strains, and neither interpreted the strain lag under shear loads. Photographs are included of the test box and assembly, loading linkage, and strain-measuring equipment. Tabulated data are presented for loadings and measurement sections and for the percentage deviation of maximum experimental strains from maximum strains of the elementary theory. Superimposed curves for comparing the theoretically predicted strains are appended together with reviews of the theoretical methods.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 16, 1952
- Accession Number
- AD0011549
Entities
People
- Bruce H. Falconer