M-Sand Quality check in field (Slilt Content test)
M SAND Quality check
Slilt Content test on site
1.)One of the problems encountered in M-Sand is the presence of Quarry Dust (silt??!! )in *exceed* quantity than the permissible limit specified.
2.)Generally, Particles finer than 75 micron (0.075 mm) are called *Quarry Dust*
3.)It is extremely difficult to separate this Quarry Dust by means of simple *Jar Test* in which mixed water and Sand are shaken in a jar and then waiting for some time to observe and measure the quantity of floating Dust.
4.)Actually the above method Works Out for *River Sand* only.
5.) *Silt and clay* being foreign materials in River Sand it is possible to separate them by Jar Test.
6.) However in case of *M.Sand* the fines coming to the top will contain even coarser particles such as *150 micron* and even more than that.
7.) It is not at all possible to separate 75 micron by this way.
8.)Any body tried this method wouldn't have got genuine result.
9.) But *wet sieving on 75 micron* sieve is the correct and genuine method done in practice and it is also *not so difficult to do at Site*
*Wet Sieving Method*
* In Wet Sieving Method sample of M -Sand in dry cindition is weighed *(W1)*
* Now It is spread in 75 micron Sieve and it is kept under a water tap.
* Then Water is added slowly and gently and at the same time agitate it by hand or brush for few minutes till all the dust goes down out through sieve.
* This can be ensured by observing the out - going water to become colourless.
* Now Re weigh the Retained material (Say *W2*) after drying it.
* ((W1-W2) / W1 ))x100 will give the actual % of *Quarry Dust*present in M-Sand
*
Materials finer than 75 micron (i.,e Quarry Dust) should not exceed *15 %* as per *IS 383 -2016*
*Note*1
Cost of 75 micron sieve is about Rs.1000 / ( Rupees one thousand only)
*Note*2
In jar (Bottle )Test if very thin layer is only floating at top it does not mean that it is a genuine M sand.
There is a very many possibility of lack of 150 micron particles and other required finer particles also.
150 micron and other finer particles are also needed in a specific % in Good Quality M-Sand
*Note 3*
Cost of Doing Complete sieve Analysis to find out Grain Size Distribution of all particles in Lab is about Thousand Rupees only.
Slilt Content test on site
1.)One of the problems encountered in M-Sand is the presence of Quarry Dust (silt??!! )in *exceed* quantity than the permissible limit specified.
2.)Generally, Particles finer than 75 micron (0.075 mm) are called *Quarry Dust*
3.)It is extremely difficult to separate this Quarry Dust by means of simple *Jar Test* in which mixed water and Sand are shaken in a jar and then waiting for some time to observe and measure the quantity of floating Dust.
4.)Actually the above method Works Out for *River Sand* only.
5.) *Silt and clay* being foreign materials in River Sand it is possible to separate them by Jar Test.
6.) However in case of *M.Sand* the fines coming to the top will contain even coarser particles such as *150 micron* and even more than that.
7.) It is not at all possible to separate 75 micron by this way.
8.)Any body tried this method wouldn't have got genuine result.
9.) But *wet sieving on 75 micron* sieve is the correct and genuine method done in practice and it is also *not so difficult to do at Site*
*Wet Sieving Method*
* In Wet Sieving Method sample of M -Sand in dry cindition is weighed *(W1)*
* Now It is spread in 75 micron Sieve and it is kept under a water tap.
* Then Water is added slowly and gently and at the same time agitate it by hand or brush for few minutes till all the dust goes down out through sieve.
* This can be ensured by observing the out - going water to become colourless.
* Now Re weigh the Retained material (Say *W2*) after drying it.
* ((W1-W2) / W1 ))x100 will give the actual % of *Quarry Dust*present in M-Sand
*
*Note*1
Cost of 75 micron sieve is about Rs.1000 / ( Rupees one thousand only)
*Note*2
In jar (Bottle )Test if very thin layer is only floating at top it does not mean that it is a genuine M sand.
There is a very many possibility of lack of 150 micron particles and other required finer particles also.
150 micron and other finer particles are also needed in a specific % in Good Quality M-Sand
*Note 3*
Cost of Doing Complete sieve Analysis to find out Grain Size Distribution of all particles in Lab is about Thousand Rupees only.
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