Grandrib 3 Test Data Summary
|Test Number||Purlin Spacing||Purlin on Edge/Flat||Rafter Spacing||Width of Diaphragm||Length of Diaphragm||Purlin to Rafter – Nail Type & Quality||Panel to Purlin – Fastener & Schedules||Design Strength||Design Stiffness|
|1||2′-0″||Flat||4′-0″||8′-0″||9′-0″||2 @ 16d, PB Nail||#10 x 1-1/2″||80.07 lb/ft||1988.63 lb/in|
|2||2′-0″||Edge||9′-0″||18′-0″||12′-0″||1 @ 40d, Common Spike||#10 x 1-1/2″||34.57 lb/ft||2082.60 lb/in|
|3||2′-0″||Edge||9′-0″||18′-0″||12′-0″||1 @ 40d, Common Spike||#14 x 1″||41.67 lb/ft||1886.20 lb/in|
|4||2′-0″||Edge||9′-0″||18′-0″||12′-0″||1 @ 40d, Common Spike||2-1/4″ x 0.120 Paslode||34.40 lb/ft||1561.10 lb/in|
|5||2′-0″||Edge||9′-0″||18′-0″||12′-0″||1 @ 40d, PB Nail||2″ FabrOseal||55.83 lb/ft||1842.42 lb/in|
|6||2′-0″||Edge||9′-0″||16′-0″||12′-0″||1 @ 60d, PB Nail||1-1/2″ Neo Nail||52.08 lb/ft||2467.56 lb/in|
- Test 1: Standard Fabral Schedule (No Stitch Fasteners).
- Test 2: Standard Fabral Schedule (No Stitch Fasteners).
- Test 3: Standard Fabral Schedule (No Stitch Fasteners).
- Test 4: Standard Fabral Schedule and nails added, 1 in every pan, at eave.
- Test 5: Standard Fabral Schedule and nails added, 1 in every pan, at eave.
- Test 6: Please inquire for schedule for Test 6. Location of nails improved stiffness dramatically.
- Tests 2 and 3 were completed with only one repetition vs. the required 3 minimum. Also, tests 2 and 3 were not “blocked” to avoid the center rafter failure situation typical of the simple beam test. Stiffness values were taken from unblocked tests only. Tests 4, 5 , and 6 were “blocked” for ultimate load testing, with stiffness values taken from “unblocked” tests.
- Weakest link in diaphragm for tests 2, 3, and 4 was the purlin to rafter connection. Loads were not high enough to bring out differences between screws and nails.
- All purlins were No. 2 SPF, all rafters were No. 2 Douglas Fir.
- Test 1 was not “blocked” – failure was not at purlin to rafter connection.