Ann: Positive Results from Concrete and Coatings Testing, page-99

Greetings fellow Androm's.
Like a lot of previous posters huge long time lurker, first time poster, ventured a bunch of hard earned mid last year to hold around 3M heads and it truly is sobering and life changing to see where this is going.

I am a general building contractor in FNQ (thats Far North Qld for the uninitiated) and for the past 37 years have specialized in all forms of concrete, large multi stories, tilt panels, civil roadworks and the like so if you will give me some grace I think I have a grasp of how things work on a site having been directly involved with around 1000 m3 a month.

Wombat correctly as ever in his post yesterday simply stated "Time costs money".

With that said let me perhaps expand on that for our non concrete cohort.

Multi Storeys.
I have recently completed a 15 storey unit complex and have waived the early strength figures under the nose of the big cheese whom ran the job. A bit of scratch work and we figured there may be a saving of a week per floor, lets not be greedy call it 10 weeks over the project.

The holding cost (admin, crane hire etc etc hurt money) on that project was $56K/ week. Now Im a simple concreature but even I can figure that out.

Tilt Panels
In brief the issue with tilt panels, because you generally pour them in stacks around the job is that the last panels you pour are by default the first panels you lift.
Basically we generally use 32 mPa mix which by the time we lift has met the mPa to lift but the last panels we pour are all "hot" mixes ie, 40, 50, 60 mPa, so when you crack a test cylinder at 7 days it may very well have met the lifting mPa.
Think I may have read a post where someone mentioned no biggie simply add more cement or, high early strength cement.
NOT the case as that stuff is dearer by a factor.@Pezz69 has elaborated on that previously and I reckon could tell us a thing re holding costs on a job.

Happy to host the 50c party say mid next year, reckon a few of you southern crew may like the freezing 16 deg winter nights we have up here, time to break out the fleecy lined blue singlet.

Big ups to all the regular ever inspiring technical posters whom so deftly guide nongs like me, @ Chingy love your stuff man.

Communication ends!

Off to the Cairns races tommorow - have a look at Paniagua!