The foundation preparation required a full day to set up the ‘bolt boxes’. As the photo below shows, a piece of plywood with 4 holes corresponds to the holes in the tower legs. The long bolts with large square washers are fitted inside waxed cardboard cones and tightened up. The cones are sealed to the plywood with a caulked sealer. These 4 ‘bolt boxes’ are accurately positioned within the steel reinforcement in height and to fit the pattern of the 4 tower legs. Cross bracing was installed to ensure no movement before the concrete arrived.
Another day and fortunately a dry one we were ready for the concrete. The specification for the concrete was a ‘strong’ mix given by the structural engineers. We opted to use a local company who mix the exact amount required on site. This means you don’t over or under order. The delivery was a little late so we used the time to dig the foundation pad for the steel access ladder for the water tower.
With the cross braces removed the concrete was poured while we stood around and watched.
Note the vertical plastic pipe in the foundation, this is a duct for the water supply. Finally, when the concrete was poured and tamped down, we all stood for a team photo. Thanks to all the volunteers who helped.
The next step is to dig the foundation for the water crane, install the wooden shuttering and add the steel reinforcement ready for the next concrete pour. When that is completed, we have to build a blockwork plinth for the water crane.