Prediction of Shear Strength in High-Strength Concrete Beams without Web Reinforcement Considering Size Effect

- Journal title : Journal of the Korea Concrete Institute
- Volume 15, Issue 6, 2003, pp.820-828
- Publisher : Korea Concrete Institute
- DOI : 10.4334/JKCI.2003.15.6.820

Title & Authors

Prediction of Shear Strength in High-Strength Concrete Beams without Web Reinforcement Considering Size Effect

Bae, Young-Hoon; Yoon, Young-Soo;

Bae, Young-Hoon; Yoon, Young-Soo;

Abstract

Recent research has indicated that the current ACI shear provision provides unconservative predictions for large slender beams and beams with low level of longitudinal reinforcement, and conservative results for deep beams. To modify some problems of ACI shear provision, ultimate shear strength equation considering size effect and arch action to compute shear strength in high-strength concrete beams without stirrups is presented in this research. Three basic equations, namely size reduction factor, rho factor, and arch action factor, are derived from crack band model of fracture mechanics, analysis of previous some shear equations for longitudinal reinforcement ratio, and concrete strut described as linear prism in strut-tie model deep beams. Constants of basic equations are determined using statistical analysis of previous shear testing data. To verify proposed shear equation for each variable, effective depth, longitudinal reinforcement ratio, concrete compressive strength and shear span-to-depth ratio, about 300 experimental data are used and proposed shear equation is compared with ACI 318-99 code, CEB-FIP Model code, Kim &Park's equation and Zsutty's equation. The proposed shear equation is not only simpler than other shear equations, it is but also shown to be economical predictions and reasonable safety margin. Hence proposed shear strength equation is expected to be applied to practical shear design.

Keywords

shear strength equations;reinforced concrete beams;size effect;arch action;regression analysis;

Language

Korean

Cited by

1.

스터럽이 없는 고강도 콘크리트 보의 전단강도 예측을 위한 새로운 예측식의 제안,최정선;이창훈;윤영수;

2.

FRP Rods로 보강한 콘크리트 보의 전단 내하력의 평가,최익창;연준희;고재용;

한국해양공학회지, 2004. vol.18. 1, pp.63-68

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