PSI - Issue 72

Albena Doicheva / Procedia Structural Integrity 72 (2025) 243–251

244

1. Introduction The transfer of forces from beams to columns during dynamic actions can threaten the integrity of the beam-column connection. Over the past 6 decades, considerable work has been done to develop a unified procedure for determining the shear force. The first definition was given in Hanson and Connor (1967). It is the horizontal force transferred at mid-height of a horizontal section of a beam-column connection. Experimental and analytical studies followed. These set various variables and their influence on the hinge response of the frame was investigated by Park and Paulay (1975), Paulay (1989), Javad et al. (2018), Gombosuren and Maki (2020), Hayat et al. (2021), Kim and LaFave (2007), Bonacci and Pantazopoulou, (1993), Alaee and Li (2017), Ramaglia et al. (2022), Doicheva et al. (2023c), Zhuang et al. (2024), Kalogeropoulos et al. (2024). In Eurocode 8 (2004) the part of the shear force transmitted from the beam to the column is determined based on a capacitive design. This is the force that is absorbed by the longitudinal reinforcing bars of the beam when the steel is yielding. We find the same acceptance in Barbagallo et al. (2023). Nowadays capacitive methods are proposed with additional consideration of the participation of the concrete section and stirrups in the joint, Shiohara (2001), Fardis (2021), Floridia et al. (2023). In Nicoletti et al. (2023) a method is proposed that allows to determine the geometric dimensions of the beam-column connection. In Angiolilli et al. (2023) a 3D model is created that allows to change the material characteristics of the construction materials used. The control of the shear force is proposed in Pagnotta et al. (2023). A machine-trained variable-angle truss model for predicting the shear capacity of RC members is proposed in De Domenico et al. (2023). All these proposed methods do not answer the question of how large the shear force actually is. In this study, the forces leaving the beam will be determined as a result of a concentrated moment load applied to a beam with certain dimensions and material characteristics of its composite elements. Determining the exact magnitude of the forces entering the beam-column connection will allow to determine the exact magnitude of the shear force. The appearance of a crack between the beam and the column and its growth will allow to track the change in the shear force in the limit stage Doicheva (2023a), Doicheva (2023b), Doicheva (2023d), Doicheva (2024a), Doicheva (2024b), Doicheva (2025a), Doicheva (2025b). The obtained results for the magnitude of the shear force will be compared with those given in the literature and prescribed in Eurocode 8 (2004). 2. Materials The Hanson and Connor definition for shear force is given by Equation (1).

(1)

j C C C V T C C V T T V           S

Fig. 1. Joint shear force in the interior RC beam – column connection.

where C S , C' S and T , T' are the compressive and the tensile forces in the bottom and top longitudinal reinforcing bars in the beam passing through the connection, respectively; C C and C ' C are the compressive forces in concrete on the bottom and top edge of the beam; V C is the column shear force. The forces are shown in Fig. 1.