(For now, one test per day would be all right. I could have time to build 8’x9’shear walls.
The whole afternoon, with the undergraduate student help(Roger Rovira or Macus Sanchez),I have I could do one test.
Another reason is I could have time to record the details, I am afraid to miss something to record.
I have planed to come to the lab in the morning, so I can build the 8’x9’ shear walls. Around the 11-12, the student comes, with the help, I can do preparation for the test and test.
After the test, write the notes.)
Cyclic test Number _3
3_4x9_OSB_Gyp_Ledger_54mil_8’up seam
Pre-test
.
Cut the corner on OSB and gypsum board to avoid the contact with the base
Marked two overdriven fasteners
Protocol: 40 circles, reference displacement is 2.4 inch.(How to get this number, will ask Dr. Yu)
There is gap under the strap, but I fix it.
Observations
Failure occurs at the seam and left edge of the board(stand in front of the OSB)
Seam:. Fastener at the edge tear out. From Left edge to the middle, 3 screws pull out, others are still okay,1 screw pull through.
36-37 circle , notice the two board start to move at the seam, but not fail until the 38rd circle
The left vertical screws pull through at 37rd circle.
At the seam location, top of the 4x7 OSB at corners ,the screw tear out.
The 1x4 OSB ,top two sides, screws pull through.
No damage show at the middle on the OSB side. .
Gypsum board: Screws upward two corner tear out, no fastener titled. Bottom is ok.
Peak load is 5060lbs, displacement is2.87inch.
More details are recorded on the data sheets.
Photos
Pre-test
After test
Pictures of the fastener deformation in the gyp board are great!
ReplyDeleteHow did the peak shear and deflection with gyp compare to the without gyp?
Any reason the pos. and neg. cycles seem kind of different in the hysteresis loop?
Great work!
Maybe better to make printed out signs designating the specimens instead of the handwritten markings -- they are a little messy, :-)
ReplyDeleteWith gyp,the average force is 4445.1lbs,average deflection is 2.65in.
ReplyDeletewithout gyp, the average force is 4410lbs,average deflection is 2.82in.
I discussed with Dr.Yu about the a little difference in hysteresis loop after the test.
ReplyDeleteThe last loop,the shear wall has reached its ultimate state,it has failed, can not bear the same load in the negative loop.It is just my opinion.
I will print.:)
ReplyDelete