Wednesday, November 30, 2011

FOOTING FORMWORK

As well as providing insulation to separate the concrete structure from the ground (preventing thermal bridging) 'Eco-block' foam insulation creates the formwork for the insitu concrete strip footings, and concrete floor slab edge. 'Eco-block' is an insulated concrete form (ECF) made from expanded polystyrene (EPS). The black bars are polypropylene connectors that attach to embedded webs. The forms arrive on site in a 'flat-pack' ready for their construction on-site.
As well as an insulant, Eco-block is used as the formwork for the concrete strip footings and the concrete floor slab edge. Service pipes that penetrate through the footings are also insulated.


Eco-block EPS formwork for the concrete strip footings

Strip footing formwork

Eco-block made up on site.







The footing work has continued to the front (western end) of the site. Concrete piles have been drilled down to bear onto solid ground, then steel reinforced and poured with concrete. The holes at the top of the piles are visible through cut-outs in the insulation through which reinforcing bars can be seen protruding.




The concrete piles can be seen beneath cut-outs in the insulation foam. 
Steel reinforcing cages sit on top.



The steel reinforcing bars protrude from withing the concrete pile






Tuesday, November 29, 2011

EXCAVATION

Excavation commenced on the site in November 2011.  Deep concrete strip and pile footings were dug to bear on solid ground which at times was up to 2m below ground level.  The deep footings and piles were reinforced with steel bars steel from EuroSteel, and poured with insitu concrete.  Once set, 50mm thick boards of 'Goldfoam' extruded polystyrene (XPS) were laid to insulate and thermally break the upper concrete floor and footings from the lower concrete foundations.  On top of the 'Goldfoam' board, reinforcing steel cages for the concrete strip footings were set up on spacers.  







POURING OF THE CONCRETE FOR THE FOOTINGS


Insitu concrete was pumped into the Eco-block formwork.  Eco-block is an insulated concrete form (ECF) made from expanded polystyrene (EPS).  The black bars are polypropylene connectors that attach to embedded webs. Concrete was pumped into place,  gently vibrated and the top surface was then trowelled off.