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1. TALAVIYA MALAY

2.  Slump test is the most commonly used test of
measuring workability of concrete.
 It can be employed either in laboratory or at site of
work.
 It is used conveniently as a control test and gives an
indication of the uniformity of concrete from batch
to batch.

3.  The apparatus for slump test consists of a metallic
mould in the form of a frustum of a cone with internal
dimension as follow
Bottom diameter = 20 cm
Top diameter = 10 cm
Height = 30 cm

4.  The internal surface of the mould is thoroughly cleaned
and freed from superfluous moisture and adherence of
any old set concrete before commencing the test.
 The mould is placed on a smooth, horizontal and non-
absorbent surface.
 The mould is filled with concrete in 4 equal layers.
Each layer is tamped with 25 strokes of tamping rod.

5.  After the top layer has been tamped, the concrete is
struck off level with a trowel and tamping rod.
 Then, the mould is removed by lifting it slowly and
carefully in a vertical direction. This allows the
concrete to subside. This subsidence is referred as
slump of concrete.

6.  True slump
 shear slump
 collapse slump

8.  True slump : If concrete subsides evenly it is called
true slump.
 Shear slump : If one half of the concrete cone slides
down, it is called shear slump. The shear slump is
measured as a difference in height between the height
of the mould and the average value of subsidence.
 Collapse slump : The collapse indicates a leaner mix.

9. NO Types of construction Recommended slumps in mm
Minimum Maximum
1 pavements 25 50
2 Mass concrete structures 25 50
3 Unreinforced footing 25 75
4 Cassions and bridge deck 25 75
5 Reinforced foundation, footing and
walls
50 100
6 Reinforced slabs and beams 30 125
7 columns 75 125

10. Malay Talaviya