Evaluation of deck fasteners functioning as shear connectors for composite steel joists

Abstract

The use of deck fasteners as shear connectors for composite open web steel joists is studied. Results of thirty-six push-off tests are evaluated in terms of strength and behavior. Six types of deck fasteners are considered. They are:

1. #12-24 Teks/5 self-drilling, self-tapping screws.

2. 1/4-14 Teks/3 with a 1 1/4 in. stand-off sleeve.

3. 1/4-14 Teks/3 with a 1 3/4 in. stand-off sleeve.

4. 1/4-14 Teks/3 with a 2 1/4 in. stand-off sleeve.

5. 0.150 in. dia. air fired pins.

6. Puddle welds (5/8 in. and 3/4 in. diameter).

All push-off tests utilize Vulcraft 1.5 VL, 22 gage, composite deck. Several modifications to the typical push-off test arrangement are made, which will permit the test to more closely model the top chord of an open web steel joist.

It was found from the push-off test results that all of the deck fasteners, tested in this study, can obtain composite action for snort span open web steel joists with the exception of 0.150 in. diameter air fired pins. A description and the results of each push-off test is included.