Title: Size Effect of Shear Failure in Prestressed Concrete Beams
Author(s): Zdenek P. Bazant and Zhiping Cao
Publication: Journal Proceedings
Appears on pages(s): 260-268
Keywords: beams (supports); cracking (fracturing); dimensional analysis; failure; prestressed concrete; shear properties; statistical analysis; structural analysis.
It is shown that the size effect prreidcted by dimensional analysis of fracturing mechanics of failures due to progressive distributed microcracking agrees with the test data existing in the liturature better than presently used strength (ultimate load) criterion, which exhibts no size effect, and better than the linear elastic fracture mechanics criterion, which exhibits much too strong a size effect. This finding is similar to that made previously for unpressed longitudinally reinforced beams. Based on the analysis of over 200 test results from the liturature, a simple design formula involving the proper size effect is proposed. Comparision with other existing formulas, including the one presently used in the ACI Building Code, reveals an appreciable reduction in the coefficant of variation of the deviations from test data.