Plate Dowel Free Movement

Summary

Plate Dowel Free Movement - These joints are similar to dowelled free movement joints however plates are used, hence the name. These plates are placed horizontally in the plane of the slab and create load transfer between panels within the slab.

Technical Information

The plates are deboned on one side of the joint using a plastic sleeve which may allow for movement both perpendicular and parallel to the slab depending upon the size of the joint opening.

There are also different types of plate dowel which are available:

Diamond, these are currently the most popular type of plate dowel and allow parallel movement once the joint has opened. The sleeves are commonly available in most countries and the plates can be formed from local high yield strength steel sheets where required. The degree of load transfer from this type of plate reduces significantly as the joint opens due to the diminishing profile as the joint opens.

Rectangular this type are less popular however they have the distinct advantage that the degree of load transfer does not diminish as the joint opens. To ensure that some parallel movement is possible the sleeves need to be larger than the plates and the dowel must be placed in the middle during construction.

Circular this type of plate dowel is available but has similar properties to the Diamond type. The main difference being that the load transfer reduced elliptically rather than linearly as the joint opens.

As with dowelled free movement joints the sleeves are placed on either wooden or steel removable formwork and cast into the first panel, the dowels are then inserted into these sleeves before the adjacent second panel is cast.

Continuous plate dowels are also available however they have proved to perform poorly in service and are therefore not recommended.