- Author
- Martin, J. W. | Rossiter, W. J., Jr. | Embree, E.
- Title
- Factors Affecting the Strength and Creep-Rupture Properties of EPDM Joints.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Book or Conf
- U.S. National Roofing Contractors Association. Symposium on Roofing Technology, 3rd International. April 17-19, 1991, Montreal, Canada, 63-71 p., 1991
- Keywords
- butyl adhesive | creep rupture life | EPDM | neoprene adhesive | peel strength | single-ply roofing | strain rate | time-to-failure
- Abstract
- The objectives of this research were: 1) to determine from a small but important set of material and fabrication variables (adhesive thickness, cure time, mechanical load, adhesive type and surface cleanness), those variables which are primarily responsible for causing joint failures; 2) to rank these experimental variables in the order in which they affect the strength and creep-rupture life of butyl-adhered EPDM joints; and 3) to determine the maximum peel stress as EPDM joint can sustain over its design life. From our results, cure time and level of cleanness of the EPDM rubber surface have the greatest effect on joint strength; while the thickness of the adhesive and the magnitude of the mechanical load have the greatest effect on the time-to-failure of a joint. It was further observed that the maximum stress that an EPDM joint can sustain over time is only a small fraction (less than 5 percent) of its short-time peel strength. It was concluded, therefore, that efforts should be made to ensure that the field-formed joints are not subjected to large peel loads.