Page 14 - Haddonstone

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3.1 Comparison of Properties of Semi Dry, Wet Cast and Fibre
Reinforced Cast Stone
The following sections carry information on aspects which may significantly affect the performance of cast stone
components:
Semi-dry Cast Stone
Close match in colour and texture and
favoured by planning authorities as an
alternative to quarried natural stone.
28 day cube strength in excess of 35 MPa.
Low porosity with weathering
characteristics of quarried natural stone.
Method of manufacture restricts size to
traditional products such as cills, heads,
string courses, etc.
Process of tamping-in material makes
complicated reinforcement difficult to place most complicated reinforcement cage.
in mould.
Can be cast as a through mix or with
facing and backing mixes.
Durability similar to quarried natural stone
with sharp arrises requiring careful on site
handling.
Cost effective production combined with
a short lead time is seen as the major
benefit of semi dry cast stone. The method
also offers the user and specifier a
product which resembles and weathers as
quarried natural stone at much lower cost.
Wet Cast Stone
Close match in colour and texture to
quarried natural stone with optional
secondary finishes.
28 day cube strength in excess of 35 MPa.
Very low porosity. Retains supplied
appearance longer.
Unit size restricted only by crane and
transport limitation.
No problems in casting around even the
Generally cast as through mix.
Durable in respect of impact damage but
still requiring careful on site handling.
This method of production can be used
for the manufacture of larger units such
as beams or cladding panels where
a combination of mass concrete and
structural reinforcement eliminates the
use of the semi-dry technique. It offers
the specifier another dimension to what is units are produced.
achievable in cast stone.
Fibre Reinforced Cast Stone (FRCS)
Close match in colour and texture to
quarried natural stone with optional
secondary finishes.
28 day cube strength in excess of 35 MPa
with enhanced tensile and bending strength.
Very low porosity. Retains supplied
appearance longer.
Unit size restricted only by mould
manufacturing and fixing considerations.
The product includes fully integrated alkali
resistant fibre reinforcing.
Cast as through mix.
Very durable in respect of impact damage
but still requiring careful on site handling.
Normally produced as thin walled products
with the reduction in weight assisting with
site and manual handling considerations.
When manufactured as thin walled units this
method of production is particularly suited
for retro fit and refurbishment projects,
and where the total weight of units is a
consideration, or it can be used to give
additional tensile strength when full sized