Moment resisting and semi-rigid connections

Design of precast concrete beam-column connections to Eurocode EC2 – Part 2

This paper, part 2 of two papers dealing with the design of beam-to-column connections in precast concrete framed structures, considers the design and construction of moment resisting (MR), semi-rigid joints, together with the results of some full scale tests on proprietary connectors. The MR connection is executed on site by adding continuity rebars, typically 2 no B25 mm, in cast insitu concrete infill in the floor zone. Under combined action of shear and negative bending the completed connections exhibit semi-rigid behaviour with fixity factors γ of around 0.7, sufficient to enhance the buckling capacity of the framework’s columns. A theoretical model is proposed to predict the moment capacity ME and rotational stiffness SE of the connection according to the strength and stiffness of the beam and the length of anchorage failure in the top rebars at ultimate limit state. A worked example is given to predict ME and SE of the connection and its consequential effect on effective length factors b in columns. Equations are presented to calculate b using the beam-column stiffness together with the semi-rigid fixity factor g. A procedure is presented to design precast columns according to Eurocode EC2. The final design of the column is not too sensitive to changes in the relative stiffness of the beams and columns.

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22.02.2024 - 24.02.2024
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