Non-bernoulli-compatibility truss model for RC members subjected to combined action of flexure and shear

Abstract

An enhanced truss model is presented in the present study. The model is theoretically based on the well-known relationship between shear and the rate of change of bending moment in a reinforced concrete beam subjected to combined shear and moment loads. The new model shows that a new perspective on the shear resistance can be gained by considering the variation of the internal arm length along the span. And the shear resistance mechanism is resolved into three independent base components; arch action, truss action and membrane action. The compatibility of deformation associated to the two actions is indirectly taken into account by employing an empirical factor. Then the base equation of V=dM/dx is numerically formulated so as to clarify the physical basis of the behavior related to beams under combined action of flexure and shear.

Strut-Tie Models and Load Distribution Ratios for Reinforced Concrete Beams with Shear Span-to-Effective Depth Ratio of Less than 3 (I) Models and Load Distribution Ratios

“…1(a)), 수직 트러스 메커니즘의 모델( ≥ , Fig. 1 [22][23][24][25] 이 연구에서는 Fig. 7과 같은 주요설계변수에 따른 하 중분배율을 정확하게 묘사할 수 있는 수평 및 수직 복합 메커니즘의 하중분배율 식   (=   ×  × , %) (a) Horizontal combined mechanism (b) Vertical combined mechanism…”

Shear Resistant Mechanism into Base Components: Beam Action and Arch Action in Shear-Critical RC Members

“…If such beam shear behavior could be decoupled into the base components, the shear resistant mechanism would be much clearly described. Accordingly, for the purpose of the present study, it is to employ a factor-a defined by follows (Kim and Jeong 2011a, 2011b, 2011c:…”

“…From the view of the gross compatibility relationship above, it can be seen that the ratio of contribution by each action to total shear resistance in a beam is dependent on the relative stiffness ratio between the chords and the web (Kim and Jeong 2011a, 2011b, 2011c.…”