Using of Robo Sand or M Sand instead of natural sand

The first advantage of M-Sand is that it is cheaper than river sand and is easily available. Check this link for all the details: Manufactured Sand (M-Sand) for Concrete -Properties and Advantages9

Supply of material not available all time and fluctuations in cost can hamper Project Cost. extraction of sand from river bed is environmental hazard and ban in many places. Contains no organic, harmful impurities, hence significant improvement in strength of concrete at same cement content.

it has a rougher texture than river sand

it has no over sized materials or silt

it provides higher concrete strength compared to river sand

it's cheaper than river sand

it's eco-friendly since m sand uses natural coarse aggregates to form

Advantages of M sand are :

Less dependency on natural sand resources 

Crushed aggregates produce lot of fines and instead of wasting , it could be mixed with natural sand and used if it passes proper gradation tests.

Disadvantageous are :

M sand by itself may not pass physical tests as required by codes.

I would rather overcome disadvantages of M sand by using controlled manufacturing process to meet code requirements pertaining to fine aggregates.

Advantages of Robo sand or M sand:

1. It is cheaper and easily available. 
2. Due to widely available, dependency on natural resources decreases. 
3. Residual of this sand is allowed to use by mix with natural sand. This reduces the wastage of material and increases the economy. 
4. It provides better strength and durability as compared to river sand. 
5. Due to rough surface or texture, provides good bonding strength.

Disadvantages and mitigation steps to overcome disadvantages:

1. Robo sand and M sand does not follow code specification values. But, Nowadays by adjusting the manufacturing process, sufficient strength should be gained with less cost.

Manufactured sand is far more better than river sand. 

Advantages of M-sand are:

• 100 % replacement to natural sand and it is one of the byproduct of aggregates 
• No scarcity as the Government is encouraging the business to garner un-tapped revenue 
• Govt. has identified the place and accorded the sanction for carrying out quarrying and crushing activities without compromising on any environmental issue 
• Sand washing machine to ensure 0% silt content, benefitting best economized concrete with possibility of reduction in cement content 
• No fear, quality is main focus. 
• Transparency in pricing as manufacturing facility is legal

The results of my project were:

Commenting on the results I would say

• M-sand is a well-graded material which falls within the grading limits specified by IS-383 for zone-II. 
• Shape of M-sand particles resemble with those of river sand particles. 
• Compressive strength of concrete made with M-sand is marginally higher(6%-9%) when compared to that of river sand.

Hence, I conclude that M-sand concrete possesses higher compressive strength when compared with river sand concrete. The results pertained to that M-sand can be 100% replaced and possess greater characteristic strength. The present investigation shows that characteristics of concrete made of M-sand as fine aggregate are superior when compared to natural river sand as fine aggregate.

Advantages of manufactured sand are as follows;

• Reducing defects in concrete like segregation, bleeding and honeycomb structure formation. 
• Setting time of concrete is comparatively fast as compared to another type of concrete where we use natural sand 
• Compressive strength and flexural strength of concrete is very high as compared to other concrete where we use natural sand 
• Permeability of manufactured sand is very less as compared to natural sand 
• It doesn't have any oversized particles. 
• Greater durability, good economy. 
• Ecofriendly building construction materials

Disadvantages of manufactured sand are as follows;

• The requirement of high water-cement ratio to achieve the desired workability. 
• Manufactured sand contains a large number of microparticles, so it adversely affects on strength and workability of concrete 
• Slump value of manufactured sand is less because it doesn't contain any moisture content (water absorption of M-sand is only to 2-4%)

Steps to overcome disadvantages of manufactured sand;

• By reducing a large number of microparticles in manufactured sand, so that the strength and workability of concrete will get improve. 
• By increasing the moisture content in manufactured sand, so that slump value will increases.

Manufactured sand: There is no doubt that the manufactured sand is not a good replacement for the river sand. We can definitely use to manufacture signed in the construction industry mainly for concrete production and mortar mix. Basically manufactured sand is nothing but a crushed of fine aggregate which is produced from the source material with suitable strength, durability, and shape characteristics. The general crashing of hard stones with the help of jaw and cone crushers we can produce poor weak and flaking particles which are for the crushed in vertical shaft impact Crusher is a waiting process to eliminate impurities and silt content from it.

Now I am discussing basic requirement to be made for producing manufactured sand, have a look:

All the manufactured sand particles should have enough or more crushing strength. The surface texture of all manufactured sand particles should be smooth and it should not be rough. All the ages of particles should be well-grounded. When you talk about the ratio than the ratio of fines below than 600 Micron inside should not be less than 30% Manufacturers and should not contain in organic impurities in it It is not possible that any impurity is not present in the manufactured sand but if it is present then it should be within its permissible limit. When we talk about silt percentage in the manufactured sand then it should not you more than 2% The permissible limit of finance below 75 Micron should not be more and 15%. (The sizes of particles which are less than 75 Micron then it includes mainly clay and silt.)

Thank you.

Hi, 

I thought you get your answer from the above comments. But as you mentioned in the question about his safety, yes the M sand safe for construction purposes up to some extent and after using some admixtures. 

Basically, rivers and is very costly. And the sands of the river selling on the base of weight. If M sand is available in the local area as it is the best choice to use. In Hyderabad, most of the power plants use a Robo sand or M sand and rock sand. Because the rivers are situated far away from the city location.