- Author
- Rossiter, W. J., Jr. | Bentz, D. P.
- Title
- Strain Energy of Bituminous Built-Up Membranes: A New Concept in Load-Elongation Testing.
- Coporate
- National Bureau of Standards, Gaithersburg, MD
- Book or Conf
- Applied Technology for Improving Roof Performance. NBS/NRCA Roofing Technology Conference, 8th. Proceedings. April 16-17, 1987, National Roofing Contractors Assoc. (NRCA), Rosemont, IL, Gaithersburg, MD, 40-49 p., 1987
- Keywords
- roofing (finishes) | performance criteria | polyesters | bitumens | roofs | tensile strength
- Identifiers
- bituminous roofing; built-up; low-sloped; polymer-modified bitumen; strain energy
- Abstract
- This study was conducted to revise the performance criterion for tensile strength of bituminous built-up membranes. Bituminous membrane samples, fabricated from polyester fabric, polyester-glass composite fabric, and single plies of APP- and SBS-modified bitumen, were tested in tension to determine their load-elongation properties and to measure their strain energy. The results of the tensile tests of the new bituminous membranes indicated wide variability of load and elongation among the different types of materials. As an alternative to the criterion that a bituminous built-up membrane have a tensile strength of 200 lbf/in (35 kN/m), it was recommended that the strain energy should be a minimum of 3 lbf in/in (13 N m/m), when tested at 0 deg F (-18 deg C) in the weaker direction.