One small correction is PCE based admixtures are 5th generation admixtures not 3rd.Many Standards states that concrete should be placed within 90 min. after batching. Nowdays many brands of admixtures are available in markets .i.e third generation admixtures (PCE based), Which are formulated to meet required slump retention time.
My suggestion is Concrete designer should carry out the trials or mock ups on re-dosing without deviating the required fresh and hardned concrete properites meanwhile you have take approval of customer.
ThanksRe-dosing in RMC generally means to dosing concrete with admixture.
This happens when, the concrete need to be maid wait for more than time for which it was initially design.
You can imagine all situation for delays, ultimate resultant is re-dosing of admixture.
What happen after re-dosing
The workability regain observed after re-dosing.
The designer of concrete should know about the limitation of use of admixture in his / her design.
He / She should check for maximum dosage of admixture which can handle without hangover by concrete and it remembers all his properties.
as said by @K Kiran , you can refer IS guide lines as mentioned by him.
I have one doubt,What will be the maximum time to unload the Concrete from RMC , When its batching time...?
Distance from my site to RMC plant is approximately it takes 1 hours (in non-traffic Time)
can you please attach the screenshot or position of location in pages in IS 456:2000 because I can not find the clause no. in book. So please update here.Please refer AMENDMENT NO. 4 MAY 2013 TO IS 456:2000 PLAIN AND REINFORCE CONCRETE CODE OF PRACTICE , clause no. 5.5.7
can you please attach the screenshot or position of location in pages in IS 456:2000 because I can not find the clause no. in book. So please update here.
Hi,What is redosing in RMC and is there any IS recommendation.