Designing for settlement - Plastic ic connections - rocker pipes

[Kencat]

I'm cutting an exist 110mm FW drain to insert a new plastic IC with 150mm conc surround. There will be various connections including one to a 2nd IC. All under a "light" vehicle access drive - this will also be used as a building and delivery platform. All with shallow inverts (less 600mm) fall 1:60 approx.
All with 50mm conc load spreading cap (not surround) to connecting l/o drains.
In relation to Rocker pipe(s).
I propose to use short pipe lengths to pass thru' the conc surround with flexi couplings (not encased) to all connections.
1.Should I place a further rocker pipe to each connection, if not to which? A complication arrises - the main l/o drain will cut and sealed at a later date - the side connections becomming the main draiage runs.
2.What material should I use to allow for movement between the 150mm IC encasement and the 50mm pipe protection?
3.Also I read that there should be no loading applied to the IC chamber. What material should I use to separate the conc. surround and the IC?

[haggistini]

I'm sort of understanding what needs to be done ..your new IC will be a 150mm mainline and will be permanent? Then some of your rockers coming off that will be encased in conc ready to recieve additional drainage after works?
Then you will install extra rockers to the ones needed not encased in conc for movement or tweeking?

If that's right I would use 400mm rockers with standard collars and incase them and the IC in conc to the top of the riser's. then just use 10mm pipe bedding to surround the temporary or remaining rockers let's say @ 400mm. You could then cover your site in conc for acsess or deliveries say at 150/200mm and then break out to reconnect your new drainage later your IC will be fine for load bearing if encased in conc its the lid and mortar that will determine the weight it will take?

[haggistini]

Encase all of the first rockers I mean

[seanandruby]

your stub pipe from your i/c through concrete surround should extend out a minimum of 150 ml, then your rocker pipe should be 600 ml for that size pipe. All concrete encased pipes should have a fibre board movemet joint at every collar extending the full width, height and depth of your concrete.