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Plain and Reinforced Plastics Need for Testing Litigation Issues When a product which contains or is made from a plastic fails causing injury or damage, it is sometimes necessary to test and analyze the particular product at issue to determine the integrity or lack of integrity of the product or one of its components. Such information becomes vital when an issue becomes a matter for litigation. EF&T has provided "autopsies" for over 25 years and worked with attorneys, insurance carriers, and other experts to help provide needed answers. Product Development EF&T works with manufacturers and fabricators of reinforced and un-reinforced plastics. Plastics, being man-made materials, can be tailored to fit specific requirements, configurations, strengths, mechanical properties and many other factors. Testing provided by EF&T can validate the specific design of a product or help determine specific areas in the design that need to be changed. Also, EF&T testing is often used for the screening of various designs or variations before extensive and expensive productions begin. Confidentiality with each client is assured. For immediate assistance, please call us toll-free at
Dr. Johnson's Comments Regarding Special Testing Equipment Required Engineering Forensics & Testing, Ltd. has a state-of-the-art laboratory for testing plastics which ASTM tests require and specify. The preparation of test specimens requires high speed diamond saws, high speed milling machines, and special ASTM jigs to insure residual stress-free specimens for accurate test results. The tensile, compression, and flexural tests require testing machines with extremely fine-computer controlled operating systems with graphing capabilities. Compression tests require the use of special stability jigs during testing. Tensile and compression tests also require the use of special electrical strain gages to determine their respective modulus of elasticity. Flexural tests require specific three-point loading devices with a means of measuring load-deflection characteristics. Fiberglass content tests require extremely sensitive analytical balances and ovens capable of operating at temperatures over 1000 degrees F. The Hardness tests require a specific Barcol Impressor as specified by ASTM.
Typical ASTM Tests ASTM designation D638 - Standard Test for Tensile Properties of Plastics (for determining tensile properties). Specimens are machined from samples of the plastic material and machined to a specified configuration according to ASTM Specifications. The ends of the specimens are then placed within grips, which when activated, place a tensile force on the specimen. The ultimate tensile force is then recorded and the tensile strength and tensile modulus are determined. ASTM designation D695 - Standard Test for Compressive Properties of Rigid Plastics (for determining compressive properties). Specimens are machined from samples of the plastic material and machined in a specified configuration according to ASTM Specifications. The specimens are then placed in a special compressive jig and compressed between two parallel plattens. The ultimate compressive load is then recorded and the compressive strength and compressive modulus are determined. ASTM designation D790 - Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulation Materials (for determining flexural properties). Specimens are machined from samples of the plastic material and machined in a specified configuration according to ASTM Specifications. The specimens are then placed within an ASTM specified 3-point flexural loading jig and downward pressure is applied to the mid-point of the flexural specimen. The ultimate downward load and the resulting mid-point deflections during loading are recorded. From this information, the ultimate flexural strength and flexural modulus are determined. ASTM designation D2584 - Standard Test Method for Ignition Loss of Cured Reinforced Resins (for determining the percent of fiberglass). In the case of fiberglass, specimens are machined from samples of the fiberglass material and machined in a specified configuration according to ASTM Specifications. The specimens, after weighing on an analytical balance, are placed in an electric furnace and heated at 1,050 degrees F. until all organic volatile materials are removed. The remains of the specimen are weighed on an analytical balance and the percent of fiberglass is determined. ASTM designation D2583 - Standard Test Method for Indentation Hardness of Rigid Plastics by Means of a Barcol Impressor (for determining if the plastic has been properly cured). The Barcol Impressor is pressed against the plastic at various locations and the depth of the impressions will uniquely determine the amount of cure.
Dr. Johnson's Plastics & Fiberglass Related Activities The following is a brief selected summary of Dr. John E. Johnson's background as it relates specifically to plastics and fiberglass activities. Was the recipient of a three-year Dow Chemical Company Fellowship to study the use of plastics while pursuing his Ph. D. at Purdue University [1960-1962]. Developed and supervised the construction of a major sports facility at Purdue University employing the use of plastics in construction. Developed major research and development programs in the use of plastics in construction and structural applications. Conducted design and research in the construction of domes using plastics. Developed and conducted major research and testing programs in structural fiberglass sections resulting in a major design manual for fiber reinforced plastics in structural applications. Developed and conducted a major program investigating the static and dynamic behavior of ladders including Fiberglass Ladders for the Consumer Products Safety Commission. This was the largest research program of this type that has ever been done. Continually testing and performing research in a state-of-the-art laboratory. Continually maintaining consulting relationships with numerous manufacturers of plastic and fiberglass products. Member: American National Standards Institute (ANSI) A14. Chairman [30 years]: American National Standards Institute (ANSI) A14.5; Standards for Fiberglass Reinforced Ladders.
Papers Published Which Deal Specifically With Plastics and Fiberglass "Factors Relating to Plastering over Plastic Foams"; presented at the Annual Meeting of the Gypsum Association in Buffalo, NY; August 1963. "A Novel Use of Plastic Foams in Highway Construction"; presented at the 20th Annual Fall Scientific Meeting in Midland, MI in 1963. "A Survey of Adhesive Structural Connections"; presented at the Annual Meeting of the American Society of Civil Engineers in Kansas City; 1965. "Sandwich Panels With Unique Cores"; presented at the Annual Meeting of the Society of Civil Engineers in Seattle, WA; 1967. "Structural Sections from Reinforced Plastics"; presented at the Annual Meeting of the Society of Civil Engineers in Baltimore, MD; 1971. "Structural Sections from Fiberglass Reinforced Polyesters"; presented at the Annual Meeting of the Society of the Plastics Industry in Washington, DC; 1972. "The Structural Behavior of Fiberglass reinforced Wide Flange Sections"; presented at the 6th St. Louis Symposium on Composite Materials in Engineering Design in St. Louis, MO; 1972. "Structural Behavior of Reinforced Plastic Beam Shapes"; presented at the American Society of Civil Engineers, Engineering Mechanics Specialty Conference in Pittsburgh, PA; 1972. "Reinforced Plastics in Construction"; published in the Spring issue of "Building Design and Construction" 1973. "Forensic Engineering Laboratory Preparation For Litigation"; Journal of the National Academy of Forensic Engineers, December 1990. "The Pitfalls of the Limited Investigation"; Journal of the National Academy of Forensic Engineers, December 1993. |