American Composites Manufacturers Association (ACMA) prepared and published Guidelines and Recommended Practices for Fiber-Reinforced-Polymer (FRP) Architectural Products.
It was ACMA’s Architectural Division that prepared these guidelines, which contain 162 pages. According to the authors, this reference book will be helpful for architects and designers who use Fiber-Reinforced-Polymer (FRP) composites as a building material.
The preface to the Guidelines states that “the ultimate decisions regarding the use of any material on a particular job must be made by the professionals involved in the project. Architects, engineers, material manufacturers, product manufacturers, and contractors must carefully evaluate the unique requirements of a project and the specifications and limitations of the materials selected.”
Information in this guideline is a recommendation only and shouldn’t be construed as standards, and this information may lose its relevance over time. All recommendations are gathered in nine chapters, covering topics from raw materials and fabrication to the installation and repair of the finished products. The information not included in the chapters, but important for builders (including examples of design solutions) is represented in twelve appendixes.
Chapter 1 Introduction describes in brief what FRP composites are, what advantages they offer, and where these materials can be used.
The authors state that transition from traditional materials to composites in the field of architecture and construction has progressed at very different rates, depending upon the specific application.
For example, composites have found widespread use in tubs, showers, and countertop applications since the 1970s due to low transportation costs, low weight, durability, and design flexibility.
In the 1990s, the transition from wooden windows and leather doors to FRP composites began. The benefits of FRP include excellent insulation properties, low thermal expansion, the elimination of rust, and improved durability. Complex facades, curvilinear shapes, and other unique architectural features, going beyond the capabilities of traditional materials, is the result of implementing FRP composites in architecture.
“As the architectural community becomes more familiar with the benefits and design flexibility offered by composites, significant growth is expected in the manufacture of these composites for construction. The use of composites in exterior siding and cladding applications will result in improved durability and decreased dead and seismic loads compared to traditional wood, concrete, masonry, or metallic materials”, states the Guidance.
Chapter 2, Raw Materials and Fabrication, is devoted to describing the most common resins and processes used for the manufacture of FRP products. Typical matrix resin chemistries include unsaturated polyester, vinyl ester, epoxy, phenolic, and polyurethane resins. Among them, unsaturated polyester resins (UPR) are the most common of the resins utilized in FRP composites.
Composites are equally used to produce products that are large or small, straight or curved, translucent or opaque. They may be fabricated as a starting material for other structures or represent a finished product. FRP composites can be produced as one-time custom pieces or manufactured in high volume.
Due to the variety of composite applications in design solutions, the manufacture of composite products is not limited to a single fabrication process. For convenience, the authors drew up a table where collected the types of fabrication processes depending on the finished products.
Chapter 3, Characteristics of FRP Composites, deals with physical and mechanical properties of composite materials. Traditional manufacturing methods, such as hand lay-up, allow you to create composites that consist of individual layers, stacked to form laminated materials. The finished characteristics of FRP composites depend on the type and percentage of matrix and reinforcement, the orientation of the reinforcement relative to the loads, the presence and type of structural core, the inclusion of fillers and additives, the fabrication method utilized, the fabricator’s expertise, and many other factors. Mechanical properties, physical properties, and other characteristics of FRP composite materials are measured using standardized laboratory test methods.
Chapter 4, General Considerations, covers general issues of fiber-reinforced-polymer architectural products. In order to facilitate the correct specification of FRP composites products and their installation for the specialists, the authors have developed the Composites Fabrications – Guide Specification for Fiber Reinforced Polymer Composites.
Chapter 5, Design, focuses on the technical issues of the design of FRP composite products. The design of FRP composite components, parts, members, and assemblies is based upon industry understood procedures such as Allowable Stress Design (ASD) and/or Load Resistance Factor Design (LRFD). Similar to the design of wood members, an understanding of the strength and stiffness of the laminate in multiple directions is necessary.
“Fiber-reinforced polymeric composite parts are often manufactured by stacking individual layers, or laminas, to create the total laminate. As a result, the applied stresses and strains within each layer and between layers are determined and are most often compared to allowable design values (ASD design) with a pre-determined factor of safety” -, stress the authors. “Similarly, the stiffness and strength of the total laminate are determined and compared to known allowables or strengths, often found from experimental testing and/or analytical approximation procedures such as finite element analysis (FEA) or lamination theory”.
Chapter 6, Tolerances describes the permissible variations from the project requirements in the process of creating fiber-reinforced-polymer architectural products. Tolerance is a permissible variation from specified requirements shown within a project’s set of shop drawings, or related specifications. Within a given project’s contract documents, tolerances should be provided, as necessary, for dimensions, locations, and other critical features. In general, the finished FRP surface should present a pleasing appearance with minimal color and texture variations from the approved sample when viewed in typical lighting from a 10 ft (3 m) distance. No other obvious imperfections such as chips, cracks, or foreign matter should be visible at a 20 ft (6 m) viewing distance.
Chapter 7, Quality Assurance, deals with the set of rules the suppliers should be aware of to assure the quality of manufactured products. The manufacturer should have an established, written Quality Control/Quality Assurance Program in effect at the fabrication facility. This QC/QA program must address raw material compliance, material storage, material acceptance, in-process procedures, verification of procedures and acceptance, and final product inspection. Prior to starting work, the composites manufacturer should submit written quality assurance procedures and product data sheets to the specifier.
Chapter 8, Loading and Delivery, is devoted to composite parts and products transportation issues. The FRP manufacturer should clearly mark or tag all FRP composite parts to coincide with project documents, including shop drawings. The techniques and procedures used for handling and preparing architectural FRP building products for shipping should be adequate to assure delivery of damage-free products.
Chapter 9, Installation, describes installation rules of FRP parts at construction sites. Efficient installation of FRP components, parts and assemblies will occur when the manufacturer, erector, shipper, and general contractor develop a coordinated installation plan. Loading and unloading, sequencing, handling, storage, lifting points and methods, and connection-point identification methods should be reviewed and approved. The FRP manufacturer should provide advice to the installer regarding unique installation methods of the FRP parts. Often FRP products can be handled with lighter equipment than that required for other building materials. The installation contractor should be familiar with the product and should communicate installation procedures with the FRP manufacturer prior to installation.
Find, please, the full text in the attached file.