JEC COMPOSITES MAGAZINE - Issue #101 - November/December 2015 - 32

environment

Fig. 5: Load testing lifting points

Fig. 7: Panels grouped and swung into position

Fig. 2: Shrink wrapped skeleton frame

painted exterior surface (perfect for multistory housing) that has window openings,
doorways, etc., already in situ, comprised
of multiple-density foams forming thermal and acoustic barriers to the outside
elements. These were produced in a oneshot epoxy vacuum infusion process on a
13m x 3m table. As this house is a one-off,
each panel is different than the next, but
you can see how easily this could be modified and replicated for mass production.
An exterior-grade epoxy was carefully

Fig. 3: Exterior epoxy prior to lay up

Fig. 4: EPP and PET foams

Fig. 6: Stainless lifting point

sprayed onto the table prior to the lay-up
of materials (Figure 3), which eliminates
the need for a painter on site and delays due to bad weather. Metyx E-glass
reinforcement and fire shield veil were laid
either side of 50-100mm PET foam and
extruded polystyrene foam. These blocks,
some pre-cut and others profiled in-house
with a hot wire and jig, were combined
with pre-sealed EPP strips (Figure 4).
Specially made threaded stainless lifting
points were countersunk and inserted at
vital load-carrying areas (Figures 5 and
6). (These were rigorously tested at higher
loads with an over-exaggerated safety
factor due to the high winds and tight
working space experienced on site.)
The panels were then finished off with a
layer of release film and all vacuumed in
position ready for the infusion. The epoxy
resin chosen for this infusion was Sicomin
SR8100 due to the mechanical properties
and flow rate required, as the laminate in
some places was up to 150mm thick. Even
small gaps in the joining of the foam created vertical 'hot spots' as the resin peaked
at exotherm, so it was critical to keep the
foam's accuracy throughout each panel.
The resin performed extremely well and
was cured sufficiently to provide a suitably
stiff panel for release and transport off the
mould table.

32 jec composites magazine / No101 November - December 2015

Fig. 8: Panel guided into position

Stage 4: A versatile system
The panels were transported in 'sections'
grouped together so that they could be
swung into position via a crane, (Figure
7) and in some circumstances were even
hand-lifted (Figures 8 and 9) into position. Seeing such large panels so easily
manoeuvred into position only highlights the possibilities of such a versatile
system. Each section was bonded to the
steel skeleton with AEC Polymer's Black
Mamba (Figure 10), a modified polymer
which offered excellent adhesion with
enough elongation to handle any thermal
expansion. Mechanical fixings were
screwed into place to hold the panel in
position while the adhesive cured. Once
the walls on both the ground and upper
levels were in place, the 'regular' trades
Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #101 - November/December 2015
