SOUNDNESS TEST FOR CEMENT BY Le-chatelier Apparatus

SOUNDNESS TEST

OBJECT

          To determine the soundness of the cement.

APPARATUS

          Le-chatelier apparatus, thermometer, trowel, stopwatch, oven, scale.

            

                                                Fig:-Showing Le-chatelier apparatus

PROCEDURE

1. Wt. 100 gm cement in the pan.
2. Now add water (.78 of the consistency) & make a homogeneous paste.
3. Now place le-chatelier mould on a glass plate & filled by the cement Paste & covered at top by another glass plate.
4. The whole assemble is submerged in the water about 24 hr. at a temperature between 24 to 35^◦C.
5. The distance between the indicators is noted (d₁).
6. The mould is again placed in water and heat is applied in such a way that the boiling point of water is reach in about 30 minutes. The boiling is continue till one hour.
7. The mould is removed from water and it is allowed to cool down the distance between the point of indicator is measured d₂.

CALCULATIONS

Soundness/expansion of cement = L₁-L₂

L₁=Measurement taken after 24 hours of immersion in water at a temp. of 27 ± 2⁰ C

L₂=Measurement taken after 3 hours of immersion in water at boiling temperature.

Calculate the mean of two values to the nearest 0.5 mm.

§  Note::In the event of cement failing to comply with the specified requirements, a further test should be made from another portion of the same sample in manner described above, but after aeration (done by spreading out to a depth of 75 mm at a relative humidity of 50 to 80% for a total period of 7 days).

RESULT

 The expansion (d₂-d₁) is not more than 10 mm.

PRECAUTIONS

§  All the measurements should be done accurately.

§  Do not apply extra pressure while filling the moulds.

§  During boiling water level should not fall below the height of the mould.