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Weephole exposed on front face of panel requires 13 mm min projection

Weephole discharging into horizontal joint below

1.29 Alternative positions of weepholes.

Although the dimensional inaccuracies in manufacture of medium-sized precast concrete panels are not likely to be in excess of ±3 mm, the inaccuracies imposed during assembly because of deviations in the frame and erection deviations on these panels are likely to be much more than this, possibly ±25 mm. Thus tolerance must be allowed in the method of fixing and in the allowable clearance between the panels and the structure to take account of such inaccuracies of construction. Allowance must be made in the design of the fixings for thermal movement of the panel (Fig. 1.31). Avoid three fixings at different

riBr^

[

J5 Cleat

Dowel x

Cleat

1.30 Various combinations of dowel and cleat fixings: (a) cleat to dowel bottom; (b) cleats top and bottom.

levels (Fig. 1.32).Two types of fixing are in common use in addition to the fixings for handling listed earlier. These are:

- angle cleats

- dowel fixings

Fixing allows for movement

Socket wrapped in polyethylene foam and taped. Loose cross pin

Fixing allows for movement

Socket wrapped in polyethylene foam and taped. Loose cross pin

Hole through beam for bolt

1.31 Allowance in the design of fixings for thermal movement and inaccuracy

Hole through beam for bolt

1.31 Allowance in the design of fixings for thermal movement and inaccuracy

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