We are known to maintain Water cement ratio for design mix of concrete. But is there any prescribed water cement ratio for cement mortars using for brick work/plastering.... Any one knows ... please explain...Thanks
Water Cement Ratio for Mortar.
- Thread starter VIDHYA SAGAR
- Start date
Dnyan Deshmukh
Staff member
Brickwork / blockwork we do at any project - Bricks or block have less strength ranging from 2.5 to as max as up to 10 mpa.
Mortar we use is to just made a bond between bricks or blocks hence having a stronger bonding material (Mortar) will lead to cracking in the bricks or block.
Plaster is weather protection coat and made to have good aesthetics of the structure. it need to be with the base on which we apply it and also should take care of self weight.
Making a high strength plaster does not give you any advantage than spending more money where it is not required and also lead to crack formations.
The above type of work requires workability in them to ensure correct application.
Mortars generally achieve strength of more than 3.5 mpa at age of 28 days.
Any ready mix mortar available in market also state the same, it will achieve more than 3.5 mpa strength at 28 days.
Hence, the addition of water in mortar proportioning is done only to achieve the required consistency for its application.
Even if you try to standardize the process, you will find following issues in it;
1. When a water content is stated and mix is done according to it, it will not give you the workability in mortar which is required in all batches.
2. low workability will lead to addition of extra water in it.
3. High workability will lead to waiting to get desired property or mason will add extra cement to achieve consistency.
4. Even if after application it does not stick to surface and settlement in applied thickness began, Mason apply dry cement on it to make it set quick. This will also lead to formation of crack due to faster hydration rate in particular area.
The plaster and brickwork mortar preparations are not always monitored by the engineer or supervisor so it is difficult to understand whats going on and what is causing the issue.
We should not allow, mason to sprinkle dry cement on surface for ease of his work.
In both work we should ensure the curing is done for at least 7days to ensure
1. Gain of minimum strength.
2. Avoid shrinkage in mortar due to no curing.
Mortar we use is to just made a bond between bricks or blocks hence having a stronger bonding material (Mortar) will lead to cracking in the bricks or block.
Plaster is weather protection coat and made to have good aesthetics of the structure. it need to be with the base on which we apply it and also should take care of self weight.
Making a high strength plaster does not give you any advantage than spending more money where it is not required and also lead to crack formations.
The above type of work requires workability in them to ensure correct application.
Mortars generally achieve strength of more than 3.5 mpa at age of 28 days.
Any ready mix mortar available in market also state the same, it will achieve more than 3.5 mpa strength at 28 days.
Hence, the addition of water in mortar proportioning is done only to achieve the required consistency for its application.
Even if you try to standardize the process, you will find following issues in it;
1. When a water content is stated and mix is done according to it, it will not give you the workability in mortar which is required in all batches.
2. low workability will lead to addition of extra water in it.
3. High workability will lead to waiting to get desired property or mason will add extra cement to achieve consistency.
4. Even if after application it does not stick to surface and settlement in applied thickness began, Mason apply dry cement on it to make it set quick. This will also lead to formation of crack due to faster hydration rate in particular area.
The plaster and brickwork mortar preparations are not always monitored by the engineer or supervisor so it is difficult to understand whats going on and what is causing the issue.
We should not allow, mason to sprinkle dry cement on surface for ease of his work.
In both work we should ensure the curing is done for at least 7days to ensure
1. Gain of minimum strength.
2. Avoid shrinkage in mortar due to no curing.
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