Monday, 6 June 2016

Slump Test


Slump test is the most commonly used method of measuring workability of concrete. the apparatus for conducting the slump test essentially consists of a metallic mould in the form of a frustum of a cone having the internal dimensions as follows:-

Bottom diameter   20cms

Top diameter          10cms

Height                      30cms

The mould is the place on a smooth, horizontal, rigid and non absorbent surface. the mould is then filled in four layer each approximately 1\4 of the mould. each layer is tamped 25 times by the tamping rod taking care to distribute the stroke evenly over the cross sections. After the top layer has been rodded, top is struck off level with a trowel and tamping rod. the mould is removed from the concrete immediately by raising it slowly and carefully in a vertical direction. this allows the concrete to subsidence. this subsidence is referred as slump of concrete. the difference in level between the height of the mould and that of the height point of the subsided concrete is measured. this difference in height in mm is taken as slump of concrete.

slump requirement for beams and slabs 50mm to 100mm

for walls and columns 75mm to 100mm

Vibrated concrete 15mm to 25mm  

No comments:

Post a Comment