Strength of reinforced concrete dowels in composite steel and concrete beams

Introduction. Connection between components of composite steel and concrete structures is the most important task in their design. Currently, a new type of anchors is popular in foreign design practice, made of reinforcing bars passed through holes in the walls of steel profiles – reinforced concrete dowels. The advantages of this technical solution are independence from the manufacturer of the anchors, relative simplicity and the absence of welding processes. It is also important to use reinforced concrete dowels in slim floors where the height of the reinforced concrete slab is close to the height of the steel beam.

The aim of the work is to develop a method for calculating reinforced concrete dowels connection.

Materials and methods. The engineering methodology based on the results of experimental research and analysis of existing international experience in calculating reinforced concrete dowels connection.

Results. The models are described; the features of the models, materials and their characteristics are given. The description of experimental equipment, schemes of testing and loading of structures are given. Schemes and types of fracture, graphical results tests of models are presented. A comparison of theoretical and experimental data is performed.

Conclusions. The main factors in determining the bearing capacity are the diameter and strength of the reinforcing bars. An almost direct relationship has been obtained between the diameter of the reinforcing bar and the bearing capacity of the model. Reinforced concrete dowels in composite steel and concrete beams make it possible to reliably combine the steel and reinforced concrete parts of the composite structure. Dowels can withstand significant loads up to 40–50 mm displacement deformations.

Based on the experimental studies carried out, an engineering methodology has been developed for calculating the strength of reinforced concrete dowels in composite steel and concrete beams.

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