Design

Provide a 15 mm chamfer to the outside edge of the nib and assume the line of action of the load occurs at the upper edge of the chamfer.

Permissible design ultimate bearing stress = 0.6/ for dry bearing

Therefore minimum width of bearing =

25 x 103

0.6 x 20 x 1000 Minimum width of bearing for non-isolated member = 40 mm Allowance for nib spalling = 20 mm Allowance for inaccuracies = 25 mm

Allow an additional 25 mm for chamfer on supported member. Width of nib projection = 85 + 25 = 110 mm

EC 2 Part 1B

The distance of the line of action of the load from the face of the beam

= 110 - 15 = 95 mm Assuming 20 mm cover to the T10 links in the beam ac = 95 + 20 + 5 = 120 mm Check minimum depth of nib.

Assuming T8 bars, minimum internal diameter of loop is 60. Therefore minimum depth of nib = 20 + 8 x 8 + 20 = 104 mm

Depth of nib = 105 mm

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