Finite Element Analysis of RCC Tie End Connections Subjected to Light and Heavy Loading

Reinforced Cement Concrete (RCC) section subjected to direct tension (when used as ring beam, truss, braced frame, etc.) is designed with special consideration such that all the load is taken by steel whereas the concrete which is weak in tension does not crack. The reinforcement detailing of RCC subjected to tensile force meeting a vertical member is provided in Indian code, SP 34 (S&T) (1987) with a notch at the connection and a proportionately larger notch with an inclined reinforcement for higher loads. In this work, the effectiveness of the notch details in reducing the stress concentration effects is studied by varying the notch sizes. The proportion of the notch relative to the cross-sectional dimensions are obtained by tracing in AutoCAD. Design of the cross section is carried out using IS: 456 (2000) adopting the philosophy of working stress method for the member under tension and limit state design for the vertical member meeting the tie. The cross-sectional shape of the horizontal member was assumed to be square with the far ends of the vertical member supported on hinge. The design of the T-assembly for a tensile load of 100 kN and the notch and cross-sectional dimensions finalized based on the traced proportions is modelled in ABAQUS for detailed finite element analysis. Results of the analysis is used to determine the effect of the varying size of the notch on stress concentration. Based on the study by varying the loads without changing cross-section of the T- assembly, the transition between light and heavy loading condition is established.