VIEWS: 43 PAGES: 3 CATEGORY: Engineering & Energy POSTED ON: 5/28/2010
(A-4) of ACI 318-05, Appendix A, have been tabulated in Table A. Keeping in mind that the strut efficiency is not expected to significantly vary with concrete strengths in the range of 16.3 to 22.3 MPa (2364.1 to 3234.3 psi) (Table 1), the following observations are made with respect to the normalized loads of Table 3: a. Among the specimens with distributed loading, the ascending order based on ultimate strengths with reference to ACI-STM provisions for strut efficiency factors ought to be UL-0-0 UL-17-0 UL-17-17 = UL-0-8.5 = UL-8.5-0a = UL-8.5-0b The order, as seen in Table 1 and Fig.7, is UL-0-8.5 UL-0-0 UL-17-17 UL-8.5-0b UL-17-0 UL-8.5-0a The order, as per the normalized ultimate loads presented in Table 3, is UL-0-0 UL-0-8.5 UL-17-17 UL-8.5-0b UL-17.-0 UL-8.5-0a The authors may like to address this inconsistency in specimen behavior. b. A comparison between Specimens CL-0-0 and CL-8.5-0 shows that normalized ultimate load and normalized cracking load of the former having no web reinforcement are significantly higher than those of the latter satisfying web reinforcement requirements of Eq. The relatively lower ratio of 0.51 in the case of Specimen CL-8.5-0 indicates that web reinforcement has significantly improved the post-cracking load-carrying capacity of this specimen. c. On the basis of the observed shear behavior of Specimens UL-0-0 and UL-0-8.5, the authors state that the horizontal shear reinforcement did not positively affect the shear strength of the specimens, and the large variation in ultimate strength between these two specimens is ascribed to the differences in concrete strengths.
in the paper is not a “vote of validation for the ACI Code 49. Bažant, Z. P., and Pfeiffer, P. A., “Determination of Fracture Energy method.” Rath
Pages to are hidden for
"Investigation of Deep Beams with Various Load Configurations. Paper by Michael D. Brown and Oguzhan Bayrak/AUTHORS' CLOSURE"Please download to view full document