Experimental investigation and stochastic fe modeling of reinforced concrete haunched beams

This thesis presents a comprehensive experimental and numerical investigation on various types of Reinforced Concrete Haunched Beams (RCHBs). The experimental work consisted of 20 RCHBs and 4 prismatic RC beams. The parameters considered were inclination angle, beam type, flexural reinforcement and failure mode. RCHBs were classified into three modes depending on the beam shape. Most influential parameters on the behavior of RCHBs were inclination angle and ratio of inclined reinforcement. Flexural behavior of RCHBs did not differ significantly as compared to prismatic beams. In addition, deterministic nonlinear finite element method was used for modeling twenty-four beams, tested within the current study and, sixty-five beams, found in the literature. Finite element model results showed close agreement with the experimental results, which implies the effectiveness of finite element models for further studies of RCHBs. Afterwards, stochastic analyses were performed, in which the parameters were assigned as probabilistic values. The modeling bias factor and the coefficient of variation of load capacity were found to be 1.05 and 0.133, respectively. Next, the limit state functions of ACI-318 and ASCE-7 codes were employed to carry out reliability analyses. The results showed that the RCHBs are more critical and have higher sensitivity as compared to prismatic beams. Finally, new mechanism modes and design formulation are proposed. Proposed formulation is the first comprehensive formula in the literature, involving all types of RCHBs.