Building Materials, Third Edition

194 BuildingMaterials

PASSING

IS SIEVE -. 1012516

RETAINED-'IS SIEVE 6 3 10125

25

20

40

25

A

Alldimensionsinmillimetres

Fig.6.5LengthGauge

DeleteriousMaterialsandOrganicImpuritiesTest(IS: 2386 Part II))

Determinationofclaylumps

Thesampleofaggregateisdriedtoconstantweightat atemperaturenotexceeding 110°C.
Samplesof fineaggregateandthoseofcoarseaggregatearegiveninTable6.4.

Table6.4 SizeofParticlesandofSievesfortheclayLumpsTest

Sizeofparticlesmakingup the

samples(mm)

Fineaggregate(retainedon1.18mm

issieve)

Over4.75to 10

Over 10 to 20

Over 20 to 40

Over 40

Weightofsample(Min.)

(g)

100

1000

2000

3000

5000

Sizeofsieveforsieving

residueofclaylumps

850 Micron

2.36mm

4.75mm

4.75mm

4.75mm

Thesampleisspreadin athinlayeronthebottomofcontainerandexaminedfor claylumps.
The clay lumps,if any,arebrokenandremovedby the useofsievesasgiveninTable6.4.
Thepercentageof claylumps,
W-R
L= --xl00
W
whereW is theweightofsampleandR istheweightofsampleafterremovalof claylumps.
Notes: 1. Thesamplesselectedfrommaterialshouldbehandledcarefullytoavoidbreakingupofclay
lumps.

2. Formixturesoffineandcoarseaggregates,thematerialisseparatedintotwosizeson4.75
   mmISsieveforpreparingsamplesoffineandcoarseaggregates.


3. Theclaylumpsshouldnotexceed 1 %forfineaswellascoarseaggregatesbyweight
   (IS: 383).

Determinationofclay,fine siltand fine dust

Sedimentationmethodisusedtodetermineclay, fine siltanddust,includingparticlesupto
20 micron.TheamountofsampletakenfortestisgiveninTable6.5.