suppose that the 21-day concrete test for foundations of a structure shows that the concrete strength is 20% less than the design requires. What can be done to address the matter??
Its for a project at college, thanks for your time.
2007-03-04 01:54:18 · 7 answers · asked by Kitzy 1 in Science & Mathematics ➔ Engineering
Well speaking from experience I usually tell the Construction Manager, who gets on the phone to the plant and gives them hell. They then send a new batch of test concrete and we start again.
The Project Manager would then try to find ways of weaselling some money off someone for the delay.
It's a tricky question because I don't have the design spec. of the concrete. Many different concrete types for different applications exist. There are rules governing admixtures, pfa's etc.
If I made the recommendation without seeing the design spec. I would be in deep do-do. I've seen 4 20ft viaduct piers brought down in 2 weeks with jack-hammers for a mistake of that nature. Not pretty.
But more hardeners and less admixtures would be the answer your lecturer is probably looking for. Of course repeating the test would be my first step.
(edit)
If the lecturer is proposing a situation where the foundations have been laid, and the structure partly built.
Then in the real world it would be a police matter, and it would be in litigation for years with the project coming to halt. But to carry the hypothesis through, I suppose steel propping, concrete cladding or a redesign of the structure would be required. At least if it's Civil. Other sectors might convince the Checking Engineer that safety factors haven't been exceeded and carry on regardless.
2007-03-04 15:52:32 · answer #1 · answered by Simon D 5 · 0⤊ 1⤋
It depends on the structure. Perhaps the foundation design has enough factor of safety, or maybe a steel plate can be added. If it is critical, get out the jackhammer.
2007-03-04 20:31:16 · answer #2 · answered by daedgewood 4 · 0⤊ 0⤋
Fondation in every aspect is of prime importance.
Anything bellow design point is prone to premature failure.
Follow the procedure and cement-concrete ratio shown in following web-sites.
It is better to repair it.You dont have to pay if you have made terms and conditiond well-planned.
Ask the contractor to make it 100%.
Pl. visit:
http://oas.ucok.edu/OJAS/99/papers/logan.htm
http://en.wikipedia.org/wiki/Concrete
2007-03-04 10:27:01 · answer #3 · answered by Anonymous · 0⤊ 0⤋
add rebarb before the concrete dries
2007-03-04 09:57:22 · answer #4 · answered by Anonymous · 1⤊ 1⤋
it needs to set longer....concrete never stops hardening
2007-03-04 09:58:13 · answer #5 · answered by ace012382 2 · 2⤊ 1⤋
Rip it out and start again.Use more hardener.and more cement.
2007-03-04 09:58:03 · answer #6 · answered by taxed till i die,and then some. 7 · 0⤊ 0⤋
you can allways underpin it!
2007-03-04 10:03:32 · answer #7 · answered by witheringtonkeith 5 · 0⤊ 1⤋