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ASTM D7379-08(R2021) pdf free download

ASTM D7379-08(R2021) pdf free download.Standard Test Methods for Strength of Modified Bitumen Sheet Material Laps Using Cold Process Adhesive
1. Scope
1.1 These test methods cover the procedure for sampling and testing the strength oflaps formed with adhesive used with polymer-modified bituminous sheet materials. 1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
6. Lap T-Peel Strength
6.1 This test method covers the determination of the T-peel strength of polymer-modified bituminous sheet material and cold-applied adhesive combinations. 6.1.1 Modified Bitumen Samples for Testing—Samples for testing shall consist of two 140 by 152-mm [5.5 by 6-in.] test panels of modified bitumen, bonded with the adhesive to be tested, and cut into 25-mm [1-in.] specimens as shown in 1. Cut the modified bitumen sheet materials and mate the sides to be bonded facing each other. 6.1.2 Sides to be bonded shall be prepared in the same fashion as a field seam is constructed with the bottom side of a top panel bonded to the top side (selvage) ofthe bottom panel using the adhesive to be tested. 6.2 Stir the adhesive to be tested until it is uniform. Spread 5.0 6 0.3 g of the adhesive evenly over the selvage portion of a bottom panel. Place the top panel over the adhesive-coated area of the bottom panel (as shown in Fig. 1) in the same manner, as a field lap would be made. 6.3 Roll the freshly prepared panel combination three times with a back-and-forth motion, taking care not to move the panels during the rolling process. No downward pressure shall be exerted on the roller by the operator. The roller shall be placed in direct contact with the 3-in. wide cemented lap portion. The roller shall be 127 mm [5 in.] 6 5 % wide, 127 mm [5 in.] 6 5 % in diameter, and shall weigh 11.8 kg [26 lb] 6 5 %. 6.4 Conditioning—Heat condition completed modified bitu- men panels prior to peel testing in a ventilated, forced-air convection oven at 70 6 3 °C [158 6 5 °F] for 7 days 6 2 h. Panels are to be placed in the oven within 24 h of preparation. 6.4.1 After conditioning, allow panels to come to constant temperature at 23 6 2 °C [73.4 6 3.6 °F] and 50 6 5 % humidity for 24 6 1 h prior to testing. 6.5 Specimens—Prepare five die-cut test specimens from each panel. Discard the outer 5 mm [0.13 in.] of each panel to avoid any edge effects. Specimens shall be 25.4 6 0.2 mm [1 6 0.01 in.] by 152 6 2 mm [6 6 0.05 in.] long. Specimens for testing shall incorporate a 25.4 6 0.2 mm [1 6 0.01 in.] by 76 6 0.6 mm [3.0 6 0.03 in.] bonded area, as shown in Fig. 1. 6.6 Procedure—Test each specimen in accordance with Test Methods D5147/D5147M, Section 6. Set the edges of the clamps apart 25 6 0.2 mm [1 6 0.01 in.], and maintain a rate of separation of 51 6 1.5 mm/min [2.0 6 0.06 in./min]. Specimen peel strength shall be measured over the interval between 25 6 0.2 mm [1 6 0.01 in.] and 152 6 1 mm [6.0 6 0.05 in.] of separation.6.7 Precision—The following data should be used for judg- ing the acceptability of results (95 % probability) on samples from the same lot from the same supplier. 6.7.1 Repeatability and Reproducibility—For materials in the peak peel strength range of 1751 to 2276 N/m [10 to 13 lbf⁄in.], S r , the repeatability standard deviation, averaged 274 N/m [1.57 lbf/in.]. The 95 % repeatability range was 6550 N ⁄m [3.14 lbf/in.] or 27 % around the true average, 2031 N/m [11.6 lbf/in.]. The reproducibility standard deviation, S R , averaged = 431 N/m [2.46 lbf/in.]. The 95 % reproducibility range was 6862 N/m [4.92 lbf/in.] or 42 % around the true average.

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