viberating concrete in hot weather?

[mynameismud]

I work for a small mid west city as a concrete finisher.for the last 11 years we have had the same sceed machine pouring winch type are lead man desided that we need more viberation to countor hony comb so we have a man walk threw the concrete with a eletric viberater.but what we are haveing happen is the concrete setting to fast does this rise the temp?

 

[DrADK]

No, faster settlement it shouldn't affect the temperature rise in a certain mix!

It has become appallingly obvious that our technology has exceeded our humanity
- Albert Einstein

 

[jheidt2543]

Concrete setting time is a function of mix design, delivery time, temperature of the concrete, and weather conditions. The method of placing the concrete has little, if any, effect on the setting time. If the concrete is setting up too fast for the finishing operations, I would talk it over with the ready-mix company.

 

[DRC1]

However, vibrators should be used sparingly. The purpose of the vibrator is to consolidate the concrete, which only takes only a a quick short shot. Once it doesnt move down any more, stop it. Otherwise you will seperate the cream from the stone.

 

[fuchsjr]

It is my understanding that properly vibrated/consolidated concrete has the vibrator inserted at each location for a few seconds at the most. The operator then pulls it out and inserts it adjacent to the prior insertion to get some minimal overlap in the zones (circles) of consolidation. If you vibrate too long, not only do you have to worry about segregation, but you also have to worry about vibrating any desired air entrainment out of the concrete.

All my concrete is vibrated. From large structures, right on down to 4" thick slabs (it takes a lot of time.

 

[dicksewerrat]

During hot weather, the concrete sets faster. Is the mixer drum a dark color? Ask for ice as a replacement of water pound for pound, maybe 25%-30%. Check the temp of the mix when delivered.