Today, we put together a series of tools for scraping and patting down the liquid concrete in the trenches. We have a range of different height of shuttering so each one needed a different tool made.
Concrete-tools
Also we discovered that the bottoms of the trenches seems to have “sunken” downwards since we had scraped and compacted the soil last week. We were testing our new tools for ease of use and making sure the gap from the flat bottoms to the level of the soil was correct at 150mm but we found it more like between 160mm and 165mm in quite a lot of places. We think this was caused by a week’s worth of water evaporation (we did double check the height and position of the shuttering itself and it is within a few millimetres so that hasn’t changed) so we will have to go around again and put in more sandy soil to bring up the required depth of 150mm.
We have ordered the concrete and they will deliver exactly 12 cubic metres as they would prefer to use just two lorry loads, rather than split it into three loads and have that extra little bit spread across all three. They will be willing to go and get another load but a minimum of 1cubic metre or more only.
We will play by ear on the day next Monday morning and if one of our independent pads doesn’t get filled, then we will just mix some concrete ourselves and pour it in on top to bring it to the correct levels.
The concrete is graded at Gen3 strength as this is what we need for our foundations, this does cost a little bit more but it makes for a better quality and we want to get it right in the first place (and only time!!).