I'm an ordinary consumer,want to know how to detect adulterated portland cement,?

Question

If by accident i used an adulterated cement , how to maintain its standard strenght. Strenght as measured in psi or pounds per square inch.

Answer 1

Gee, that's a major problem. Adulterated cement! Who in this world is so malicious to adulterate cement? That's why buildings collapse! For Christ sake.
Ok, now, If you already used the cement, well, there is not much to do. Have you done the compression tests? If it does not comply with the standard, don't think it too much. Tear apart whatever you have done and build it again using good cement, have samples of the cement analysed by SEM, and sue whoever sold you the bad one. The problem is what have they used to adulterate the cement, because there are a number of elements that affects its chemistry. You will never be sure what it could happen. It is not only its strenght but also its toughness, stability over time and the effect of intemperism.

Answer 2

You could have it tested but it would cost you. There is little chance of you testing it yourself.

I would think it extremely unlikely someone would try and do such a thing. The cost of mixing and re-bagging would far out way the gain.

You should also bear in mind that bag cement does not necessarily undergo the same stringent testing as that sold for concrete products or ready mix anyway. The bag market is a very small percentage of any cement manufacturers output. I'm not saying manufacturers don't care but you may work it out how concerned they might be about quality in bags that are never tested. Large bulk customers will do their own testing so it has to be good.

Answer 3

Buy your cement from reputable dealers like Home Depot, or Lowes. Make sure the bag is labeled Portal and Cement and it has not been tampered with before you buy it from anyone else. Cement isn't that expensive, it has to be a pretty cheap and unreliable company that is going to try and sell you phony cement.

Once you have the cement you can't easily get the phony ingredients out of it, it is cheaper to toss it and get some new stuff.
This website: http://www.homeandbeyond.com/prod-0114955.html
Quotes it at $16.12 per 92 lb bag, and that was just the first one I looked at with a Google Search.

Or you can order it direct from the concrete company delivered in a truck. The small price they would save by cheating you wouldn't be worth the loss of business if any of their concrete ever failed. Engineers and Architects provide specifications and if those specs are not meet then the law suit that could come out of it could be worth millions. No company is going to want to take that chance and they are going to supply you with the same concrete batch they mixed up for ALL their customers that day; including professional contractors.

The proper way to test fresh concrete is to perform a slump test. The still wet, mixed, concrete is poured into a special cone and then the cone is removed. The degree of slump determines the type of concrete. As per the method showed on these websites: http://www.polysteel.com/manual/ps3000/ps3000m141.pdf
http://www.tpub.com/content/engineering/14069/css/14069_550.htm

Humbolt: http://www.humboldtmfg.com/c-2-p-266-id-2.html
Sells them for over $100, but you should be able to rent one at any construction supply company. Then download the testing manual and do the test.

If you are in the UK then check out this site: http://www.ele.co.uk/pdfs/70-71.pdf

After the concrete has cured and hardened then you have to take a cylinder to a lab to have its breaking test checked.
Read this Wikipedia article: http://en.wikipedia.org/wiki/Concrete#Concrete_testing
and check out the section on testing.

Answer 4

there are few things that affect cement strength
* water cement ratio
*curing time
*amount of aggrigates and sand
i dont remember these things exactly but ask any construction warker he will tell u about them