Issue link: http://alpine.uberflip.com/i/915756
129 (800) 521-9790 alpineitw.com end of the joist simulator. The dial indicators are generally located on the top of the joist to prevent damage in the event of an early failure of the assembly. A number of readings are taken at set intervals to establish a load verses deflection curve. The interval that the readings are taken is usually based on an estimation of the connectors allowable load capacity with 10 readings yielding a reasonable deflection curve. After the 1/8 inch deflection has been established based on the dial indicator readings the indicators are removed and loading continues until the ultimate capacity of the assembly is reached. 6) Once the ultimate capacity of the test assembly has been determined the load will be divided by 2 because there are two connectors per assembly. This load is now the ultimate tested load for each connector. It is a requirement per AC13 that when 3 tests have been run that no individual test can vary by more than 20% from the average of all 3 tests otherwise 3 additional tests are required. The lowest, NOT the average, ultimate load per connector must be divided by a safety factor of 3 to determine the connectors allowable capacity based on testing. 7) Another very important part of a correctly conducted test is the failure mode, which is the significant element of the test assembly that contributed to the ultimate load. In the very large number of tests conducted using Alpine manufactured products, the failure mode can be anything from wood crushing and or splitting, to actual connector failure, or as is very often the case, the fasteners, nails, bolts, screws, used to connect the hanger to the wood will break or pull out. As can be seen from this it is very important that the fasteners specified, both size and quantity be used for the connector to perform in a manner consistent with the allowable loads published. It is also very important that all of the correct fasteners be installed before the connection is subjected to any load. As is evident from the preceding discussion and review of the figures the mere presence of a test does not mean that the test has been done correctly or that it necessarily reflects actual field use of a connector. Alpine does testing at its own facility for the determination of published allowable loads under the supervision of an accredited third-party lab. Typical Test Set-Up Test Set-Up Note 1 ⁄8" Teflon Spacer Typical Test Set-Up