Vibrating beam screed failure

[Pete]

Hi All,

!6 cube of concrete booked for 11am today. Batch plant broke down approx 3miles from site but did not find this out until end of first pour. Upon asking how long till the next load I was informed about an hour as he has to go next nearest batch plant. I was not happy but what can you do. By approx 3pm all concrete in place and started to finish the screeding. The beam screed was 6.2m long with two vibrating units on it and it weighed a ton. With about 2 metres left to do the belt  on one of the units was playing up and started vibrating badly. At this point the wooden beams that are used to secure the engines to the beam came loose due to a combination of excess vibration and the securing threads on some of the bolts had been stripped. Then the unit completely packed in as the shaft that drives the belt had a severe bearing failure.(stress level rising by now.) By the time we had removed the whole beam, removed faulty engine, cleaned beam and relocated it was past 4pm and it was at this time that we made a bad decision. As the we looked at the concrete we realised it was a mess where the wooden beam had dropped out,when we placed the beam back it left a big mark right across the slab. We decided to go over the whole slab again with one engine ( rung hire company and they did not have another) and it was a nightmare.Trying to pull that beam with only one engine on concrete that was starting to set was horrendous and thus we have ruts across the slab spaced evenly as I took a step to start the next pull.  

So the reason for the rant I now have a slab that  is sort of ok for a garage but if you had seen the finish of the concrete before it all went wrong you would be as disapppinted as me. I rushed to the hire company just before closing to get a bull float but it would not even touch it. Would a power float touch it tomorrow? Or what else could I do? 

SWMBO said it looks ok as it only a garage but every time I go in there I will be reminded of the day when it all went wrong through no fault of my own.

TIA

[Russell griffiths]

I feel your pain. Been there done that. 

 

 

 

I would say that a power float will not touch it tomorrow. 

1. You could hire a scabbler and knock all  the high spots off, then when cured you could use a floor leveling compound. 

2.you could get a company in to grind the surface and then clear epoxy it. 

3. If you intend spending a fair bit of time out there I would use a levelling compound and then a nice vinyl tile. 

 

[Pete]

I have same thoughts. Will see what it is like when  the garage is finished and may use self leveling if needed. 

[Russell griffiths]

As this is a place for sharing knowledge, I will pass on something I work to, first truck needs to be on site for 8.am, no later if they can't do this I don't want it, this gives you a couple of hours to get it in place and still plenty of time for cock up factor. 

The only time I will have it any later is if it's being poured straight into a mass footing. 

This is not a dig at Pete but hopefully a useful tip for anybody contemplating a bit of concreting. 

[jamiehamy]

I don't have an answer but our garage pour was not dis-similar. The concrete was the wrong spec (was supposed to be the not self levelling self levelling stuff, but turned out as normal c35 which was a real pain to move as it didn't flow well. Then there were big gaps between the loads arriving which caused issues with the smoothing off. The finished surface is less than satisfactory, but it's a garage and I'll be covering it anyway.

These things do happen - you just had more than one at a time. You've got the rest of tonight to be annoyed then forget about it - you can do things to make it better but you can't go back and undo the concrete