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Shaking Table Testing of a Reinforced Concrete Frame with Biaxial Response.
Oliva, M. G.
National Science Foundation, Washington, DC., October 1980, 207 p.
Identifying Number(s)
The program in this report involved testing of a one third scale 2 story reinforced concrete frame, having rectangular section columns, with inelastic biaxial motion induced through earthquake excitation on a shaking table. Close inspection of the experimental response, and comparison with previous test results on a similar frame under pure uniaxial motion, found that biaxial motion seriously reduced the column yield strength. Local and global response characteristics indicated a tremendous amount of interaction between the rectangular column's strong axis motion and weak axis response. Weak axis stiffness was reduced to less than one third the initial value, through strong axis interaction, associated with narrow hysteretic load-deformation response, characteristic of a low energy absorption mechanism. Analytical correlation with experimentally measured response, considering response independently along the frame's major axes, was unsuccessful. Necessary modifications to current analysis techniques, for accurate modelling of multi-axial loading, including biaxial bending, of reinforced concrete members is discussed.
Dynamic response; Buildings; Earthquake engineering; Earthquake resistant structures; Loads (Forces); Reinforced concrete; Windows; Columns (Supports); Yield strength; Dynamic structural analysis