1 September 1999
facilities not used for human occupancy. For additional guidance on the design of fabric
structures, see Tension Structures Behavior and Analysis by Leonard and refer to literature
available from the major manufacturers of structural fabrics and air-supported structures. Use
of fabric structures is subject to prior approval as set forth above except when they are used
as temporary enclosures.
13-6. GLASS FIBER REINFORCED CONCRETE, FIBER COMPOSITES AND REINFORCED
a. General. Although the use of glass fiber reinforced concrete (GRFC) is used in many
instances for building cladding, the use of other fiber composites and reinforced plastics has
been very limited with respect to building systems and components. These materials do offer
unique advantages because of their high strength-to-weight ratio, because of the ease with
which they can be molded into various shapes, and because of the excellent resistance they
provide against corrosion. Other properties such as creep, modulus of elasticity, coefficient of
thermal expansion, and long term resistance to weathering and other environmental effects,
however, may result in overall performance that does not measure up to the standards
associated with the commonly used materials described in the previous chapters of this report.
b. Glass Fiber Reinforced Concrete (GRFC). Glass Fiber Reinforced Concrete (GRFC)
consists of cement aggregate slurry reinforced throughout with alkali resistant glass fibers. In
building construction, GRFC is primarily used for architectural precast cladding. The cladding
has an appearance similar to precast concrete, except it is much lighter which can help to
reduce the cost of the building structural framing. GRFC is not used as a vertical load-bearing
component, although it can resist wind loads, and seismic inertial forces due to its own weight.
In addition to being lightweight, GRFC panels have high impact resistance and are non-
combustible. Information on use, design and construction of GFRC can be found in the
Prestressed Concrete Institute (PCI) Committee Report, "Recommended Practice for Glass
Fiber Reinforced Concrete Panels." When used, GFRC should be evaluated for its history of
performance under the types of climatic conditions to which the building will be exposed.
Climates with temperature extremes and with high rainfall and moisture conditions have in
some cases have caused deterioration of GRFC thereby effecting cladding serviceability.
c. Reinforced Plastics and Fiber Composites. Construction using fiber reinforced
plastic and fiber reinforced plastic composites is relatively new with respect to structural
applications. Glass fiber reinforced plastic (GFRP) bars can be used in concrete beams and
columns in order to prevent damage from the corrosive effects of salts, acids, and other
aggressive elements. The ultimate strength of GFRP bars is about twice that of reinforcing
steel, however the modulus of elasticity is only about 1/4 that of steel that could possibly cause
serviceability problems related to increased deflection. Glass fiber reinforced plastic (GFRP)
plates and fabric can be epoxy bonded to concrete or masonry to increase strength and
ductility. This shows great promise as a means for increasing the structural performance of
existing structural systems and components, especially where structural components lack the
strength and ductility to survive major earthquake ground motion demands. Information on
reinforced plastics and fiber composites can be found in the ACI Journal Technical, Paper,
Title No. 91-S34, "Fiber Composites for New and Existing Structures," May-June 1994.