This paper, part 1 of two papers dealing with the design of beam-to-column connections in precast concrete framed structures, considers the design and construction features of simply supported pinned joints. Two generic types of connections are discussed – concrete corbels and hidden connections with mechanical components such as steel billets, cleats, and narrow plates. Part 2 considers how the same types of connections can be designed and constructed as moment resisting with partial strength and semi-rigid stiffness. The main conclusion of this paper is whilst concrete corbels are the most fundamental to design, based on the strut and tie method with shear and anchorage resistance, they are visible below the level of the structural zone and hence often objectionable to architects. On the other hand mechanical connectors, designed using statical equilibrium and out-of-plane confinement both in the beam and column, are concealed within the depth of the beam, leading to shallower structural zones. Some of these connectors are found to have up to 600 kN shear capacity within a 600 mm depth of beam. Although Eurocodes now provide sufficient information to design these connections without making assumptions, in the presence of cracking and complex 3-d behaviour, there is often a need to prove the ultimate capacity using full scale tests.
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