I am posting some pictures of different mixes that we took on the west coast of Florida. The first one is a 50/50 slag mix that pumped quite well. The rest of the pictures are mixes from the same supplier, same mix # and many the same day as the first.Those mixes did not pump very well if at all.

Does anyone see a difference between the first pic and the rest of the pics?

Does anyone know what an operator can do to make those mixes pump?

Does any one have any suggestions for what can be done to a pump to make those mixes pump?

Bonus question:

Can any one guess who the supplier is that brought these mixes on the west coast of Florida?

I've been pumping since 1985 and can tell you that I've got a fairly extensive knowledge of mix designs. I would just like to hear your opinion.

west coast of Florida? u mean the panhandle?

Tampa Bay

First thing get a Putzmeister      I think your contract should stipulate a pumpable mix      Try and pump it         If the mix is not pumpable bill the contractor and go home       Take the upper hand     Or move to Louisiana and pump some of our natural sand and smooth river rock

Thanks Bis,

I've got 7Putz's and 2 Schwings.  What I am asking for is a response from the experienced guys that will back up my claim that the concrete you see in the pictures looks boney and unpumpable and that no operator expertise or pump adjustment that you can do will make an unpumpable mix pumpable.

Would anyone like to back me up on that ANd comment on what they see in the pictures?

honestly if the pumps wear parts are tight , and you can't pump it , without adding water or a pump aid chances are you aren't going to be able to pump it, if you are limited to making a pump pump a unpumpable mix without having the ability to add water or pump aids , you are pretty much screwed , I've been running pumps since 1989 and have very good knowledge of mix designs , we can't just wave a magic wand and make machines do the impossible I do not care how good you think you are , you can mess with rpms and output , water , pump aids , pump through all 5" line or hose , but that's about it, if you've done all these things , then it's not on you.

Thank you pudg....just what I was looking for.

Any one else.

In my opinion (for what it is worth) the 1st pic it looks ok plenty of sand if I had to guess I would say 40% sand to 60%rock the 2nd pic has way more rock and very little sand 25%sand? I would be surprised if anyone could pump that. The 3rd pic it is hard to see it might have gone in   bigger hose if it was a lot wetter.  Best of luck getting things straightened out. 

1st and 2nd pics looks pumpable. Middle picture looks the most pump friendly. 3rd picture looks really lean on cement batched or over sanded.

You could get the mud moving, try running auger in reverse away from cylinders run half full hopper to draw air into the cylinder with the concrete. Obviously cutting ring seal as spectacle plate wear should be in reasonable condition. Looks like, The more water you add on the 3rd pic the worse it will be to pump, less aeration = more compaction.

Actually I'd be happy if I couldn't pump the 3rd pic it reminds me of independent concrete plants in the early 90's. I remember (as a greenhorn) when you had breaks in pumping water would literally be trickling out of the end hose. Quite a anxious feeling knowing you would be stripping elbows of the boom within the next 15-30 mins or so...

have a plant here that like to sell boney mixes based on rock strength, that looks like the first load.

the second mix is a total joke. third has no fines so coating the rock to be a hydraulic product will not happen. they know that you are pumping they just do not care to provide the product that cuts into the profit to deliver a good material. 

Todos a esta altura sabemos que hormigon se bombea cual sera dificilmente bombeable y cual volvera en el mixer que lo trajo. Tu bomba sera el fusible de lo que le entro dentro. SOBRE QUE HACER SIMPLEMENTE NADA TU BOMBA TE LO DIRA GRACIAS

1st mix...looks average.  2nd looks like well above average on stone for the mix ratio...

3rd looks like someone done the quick and dirty in mixing, or got about 50% too happy with the sand addition.

Too much sand, coupled with slag that Im assuming is porous stone, is going to absorb all the water content... leaving you with dry stone, too much sand, and too little water and cement.  Going to be hell to pump..would it be possible to prewater the stone pile and back off the sand just a bit in the mix, and ADD cement/flyash?  Oh yeah, water would be nice too!!!

Ive been gone a while, but thinking 50/50 ratio on stone/sand and 80/20 cement/ash...

I think what you guys call slag, we would call light-weight stone??