Raining today, so a day of rest and Gabdion step design development.
I'm going a bit mad with this design aspect now because there's virtually nothing on the internet about Gabion step design and construction, so this may be of some use to others. If you pick up on it in May 2021 - just follow the blog and you'll see how it comes together and whether it works or not. *Note I live in an area where everything is built on 'London Clay' and it's metres thick!
Had some ideas about the steps which will start on Sunday or Monday. As this gets nearer and the more I think about it logistically, the more complex it gets. I need to re-design the step structure in terms of stability and I've realised I've not built around the Gabions used for the steps and that the Gabions will now have to fit within a gap of 70cm. This issue there is whether the grids are going to fit 70cm. You'll see what I mean later.
Things to do
(1) Pick up concrete disc from Argos.
(2) Measure the gap between the Gabions and see how that works out in terms of the Gabion risers on the steps.
I've redesigned the structure of the steps see below with the stability of the steps in mind and also as a way of getting rid of all the old flagstones, although this is highly reliant on my mate across the road letting me hang on to his massive disc cutter as I'll need to cut the paving slabs up into neat sections.
One of the potential issues is when I place the 'Tread' slab onto the Gabions I don't want it moving around, so I'm thinking, if I make some concrete nodules and glue these onto the under-side of the Gabions this will mean there's a lot less scope for movement as the nodules will sit in between the Gabion grids.
Steps design/structure MKII
(1) Is the 'Tread' slab (Indian Sandstone). These will sit on the Gabion and be held into position with specially made 'Nodules' (4) glued to the under-side that will sit in between the grid pattern of the Gabions. Whilst also sitting on and being supported by old school concrete flagstones. They might also be glued to these as well?
(2) Is the Gabions
(3) Are the concrete flagstones A,B,C and D, these will form a solid base onto which the Gabions and the tread slabs will be supported. *I've got a load of these which all need to come up before Phase 4, so rather than get rid of them which is (a) Expensive or (b) difficult and hard work, I may as well use them as part of this design and hopefully they'll help to make it a really strong structure?
Step width issue...
This image below shows the Gabion width and height in relation to the gap the step have to fit between...
7 Grids are 537mm, which is 37mm too long as either side of the Step Gabion will be railway sleepers which are 100mm thick. (Below)
(a) 7 grid Gabion 53.7cm (b) Railway sleepers stood on their ends 10cm wide. (c) Total width to work with 70cm.
Modifying the sleepers so that they're narrower is unrealistic, so the Gabion will have to be cut down to fit the gap.
So the Gabion will be six grids wide with spikes at each end and a bit of a void at the sides indicated by the orange part in the image below (f). In theory this void is less than 20mm either side. The red lines (g) indicate the end grid holding the stones in. If I researched it, there's a chance that I could use the void to put some kind of lighting in to light the stairway? But they wouldn't be easily serviced, so in the longer term that might not be an idea to go with.
I think I need to mock this up somewhere on the flat to get an idea of how it works in practice and that'll allow me to iron out any further issues before I go ahead with it. Diagram below approximating the steps and sleepers.
MK III version. This now has the Gabion sitting over -lapping the sandstone, but primarily supported by something else (As yet undecided) but some form of cheaper slab or perhaps cement? in the void indicated by the blue hatched area, or perhaps custom made slabs made with a mold and concrete?
No comments:
Post a Comment