Literature Review on Building Envelope, Heating and ... - Beeshive.org

Composite-Wrapped Concrete Column
Karbhari and Eckel (1994), similar to Pathak (1996), noted that degradation of
mechanical properties of concrete materials exposed to sub-zero temperatures is a
problem in regions, such as the arctic. As a solution, Karbhari and Eckel proposed the use
of composite materials. Composites are attractive for cold region applications due to their
high strength-to-weight and stiffness-to-weight ratios. They are lightweight (and hence
easily assembled), and are resistant to the environment.
Karbhari and Eckel investigated the effects of cold temperature, -18ºC (0ºF) (60 days
conditioning), on the strengthening efficiency of three different composite-wrapped
concrete columns. The composites tested were glass fibres, carbon fibres, and aramid
fibres (Kevlar 29®). They also discussed the differences in the failure mode of the entire
structural element, the composite wrapped column. They concluded:
• For both glass and carbon fibre reinforced composite wraps, the compressive strength
and rigidity increased as the temperature decreased.
• A carbon fibre jacket appeared to be the best in terms of structural performance, but
its failure mode was catastrophic. The failure mode for glass fibre was better as a
more benign mode of gradual failure.
• The use of carbon glass hybrids would provide the optimum combination.
Neale and Labossière (1998) studied the effectiveness of using fibre-reinforced
composites for structural rehabilitation and strengthening in a severe cold climate. The
authors reviewed field applications in Quebec involving structural elements, such as
exterior building columns, columns of a highway overpass, partially submerged bridge
piers, and beam and column elements of a major parking garage structure.
Scandinavian Region
Steel Construction
Aromma (1999) and Sandberg and Nieminen (1997) studied the hygrothermal
performance of a full-scale wall assembly using laboratory testing, three-dimensional
computations, and field measurements to demonstrate the performance and suitability of
using perforated-web light-gauge steel (1.2 to 1.5 mm/0.05 to 0.06 in. thick) structures
for houses in the cold climate of Finland. The perforated web of the steel improved the
thermal performance of the steel structure by providing a thermal break, which reduced
thermal bridging along the web by 70% to 80%.
Four buildings, three row houses, and an apartment building were built in 1996 to
demonstrate the suitability of steel structures for Finnish buildings. The houses were built
using steel as load-bearing materials in walls and roof trusses. The houses also included
stiffening insulated wall panels, prefabricated bathroom modules, and so-called new
“snap-on” roofing panels (Aromma, 1999). One of the row houses was designed as an
energy-efficient house with targeted heating energy consumption of 50% of that of a
reference house built according to the Finnish building code.
PERD-079: Task 2 - <strong>Literature</strong> <strong>Review</strong> 57