The junctions of tank wall and base slab with neat sketch
Joint in the concrete introduced for convenience in construction at which special measures are taken to achieve subsequent continuity without provision for further relative movement, is called a construction joint. A typical application is between successive lifts in a reservoir.
The position and arrangement of all construction joints should be predetermined by the engineer. Consideration should be given to limiting the number of such joints and to keeping them free from possibility of percolations in a similar manner to contraction joints.
A gap temporarily left between the concrete of adjoining parts of a structure which after a suitable interval and before the structure is put into use, is filled with mortar or concrete either completely ( Fig. 5A) or as provided below, with the inclusion of suitable jointing materials ( Fig. 5B and SC). In the former case the width of the gap should be sufficient to allow the sides to be prepared before filling.
Where measures are taken for example, by the inclusion of suitable jointing materials to maintain the water tightness of the concrete subsequent to the filling of the joint, this type of joint may be regarded as being equivalent to a contraction joint ( partial or complete ) as defined above.