Material Storage....concrete slab finally

We have poured several concrete pads or slabs since I have been here: the base for the chemical storage building, the base for both pump houses, the mix and load area, the base for one of the cold storage buildings and the base for the fuel tank. Some we have had help and some we did solo. Usually the help has been from my brother Chris who has a concrete form business in RI and also dabbles in flat work or slabs. I wasn't sure if we would be able to time it right to bring him out this time but our delays helped out the schedule so he came out last night and helped us manage this part of the project. Concrete work is a specialized field and as you add chemicals to speed up the curing process in colder temperatures it adds and added stress to getting it done in a timely fashion. It can be very tricky this time of year playing the weather game: will it drop below freezing at night so you have to protect the concrete as it cures by adding hay and tarps for insulation etc. We timed it perfect where it will be warm tonight and we added just enough chemical accelerator for the pad to be firm enough by nightfall so that the rain predicted tonight will not ruin the finish. It could end up looking like the hood of your car after a massive hail storm full of pock mark dents.

getting started: first of 3 trucks

Notice the steam coming off on the right side

1 truck done. Chris starts the finish with first bull float



last truck. see the finish taking shape

to put the "finish" on concrete you first run a tool over it called a "bull float". This pushes the gravel down and brings the cream up to the surface. This cream is what you would trowel to a smooth surface on a smaller area or an area that requires a smooth surface. They make powered trowels for large surfaces like this one. We do not need or really want a smooth surface so we will bull float and then run a tool called a "fresno". The fresno is steel and seals the surface as opposed to the bull float which is magnesium and does not seal the surface. It is important to seal the surface for structural integrity and weather proofing. I tried to insert some videos showing the fresno and broom finish taking place but to no avail. The following pictures will have to do:

applying the final finish by dragging a brush across top

close up of brush finish. notice fiber strands instead of steal reinforcement

1/2 and 1/2 waiting for surface to be ready for final step

Chris applying finish edge to a section brushed

finished product from office window

We will give this concrete a week to cure before placing the blocks on top. We will attempt to cut in expansion joints tomorrow depending on weather.