The dowels will be debonded on one side of the joint to allow free movement, this is usually in the form of a plastic sleeve which the dowel sits in.
During construction it is common for the sleeves to be placed on removable formwork, either wooden or steel, so that they are cast into first panel to be cast. The dowels will then be placed into the sleeves in time for when the adjacent panel is cast. Care must be taken to ensure that the sleeves remain straight and level during casting to prevent the dowels being at angels when the second panel is cast. If the dowels are at angles then restraint will be created which could lead to shrinkage cracking.
Often the sleeves used for this type of joint only allow movement perpendicular to the joint which can cause problems if movement parallel to the joint occurs. Face Consultants advocate the use of dowel sleeves which allow movement parallel to the joint, these often take the form of a rectangular plastic sleeve which contains a compressible material at the longest edges to ensure a snug fit during construction but also allow movement parallel to the joint.
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