Ninth week

From Peng

To file

12/6/2011

Test13

13-8’x9’-ledger-OSB-GYP-8’up seam

Pretest

Put the shear wall in the test frame first, then put the gypsum board on it, clap them, drill screws and cut half inch at the bottom. Look good.

Check the OSB side, one fastener at vertical bottom close to the OSB edge.

Other fasteners are okay.

Photo 

Meanwhile, we are doing the fasteners and OSB(horizontal and vertical strand) connection test.

Ninth week

From Peng

To file

12/6/2011

Test12

12-8x9-ledger-OSB-54mil-8’up seam cyclic

Pretest

43circles

Reference displacement:2.92x0.6in.

8’x9’ shear wall, horizontal seam at 8’up.Vertical seam at 4’over.

Strap is good.

2 over-drilling screws at the horizontal seam recorded

Anchor spacing is 2’

After test

Peak load+:10049lbs

Displacement: 2.2672in.

Peak load-:-8443.1lbs

Displacement:  -1.6616in.

The failure occur at the bottom, fastener pull through OSB with titled

Fasteners up to 2’high on the chord studs pull through the OSB

At the bottom vertical seam which is up to 1’, the fasteners fail with wood bearing failure and pulling through OSB.

The strap is good, no damage observed

The outside of the horizontal seam tear out.

The connection of the vertical and horizontal seam is broke because of the contact.

Fasteners in the corner at the bottom are cut off the head.

Photo

 After test

Bottom fasteners (1)

 Bottom fasteners (2)

 Bottom fasteners (3)

 Bottom fasteners (4)

 Bottom 

Ninth week

From Peng

To file

11/30/2011

Test 11R

11_Retest_8x9-ledger-osb-54mil-8’up

(stud: 600S162-54mil(33ksi))

Everything looks good.

We use 600S162-54mil(33ksi) as our field studs and chord studs.

Strap is good, no gap.

After test

Peak load:8708.3lbs

Displacement: 2.4182in.

Failure occur at vertical seam and OSB bottom, fasteners titled then pull through.

Failure is at one of 4x8 OSB on south side.

Fasteners at vertical seam on south side complete pull through,

3 fasteners at horizontal seam near vertical pull through

3 fasteners at the bottom near vertical seam pull through.

At the edge of  horizontal seam, OSB tear out.

Fasteners on south side field stud title, no damage.

Observe all the fasteners at the strap and bottom title.

Photo

 After test

 horizontal seam and vertical seam

 After test 

 Middle field stud

 Bottom of vertical seam

 Fasteners at the strap

Fasteners at middle field stud

Eighth week

Assemble another 8'x9'shear wall today.
Double check the details.
Will do monotonic test with Dr.Yu tomorrow afternoon.

Photo

Eighth week

1.Put the ledger on, test the stiffness.
Stiffness:166.6lbs/in.
2.Put the OSB on, ready to test tomorrow afternoon.The first 8x9 monotonic test.

Photo

                                      

Eighth week

1.Put the 8'x9' frame in the test frame.(Move the roller to adjust the 8x9 shear walls)
2.Test the stiffness.(Give 1in.displacement)
Stiffness of the 8'x9' stud to track frame is 94.15lbs/in.

Photo

Seventh week

We have already done the test number9 and number 10, will update later...
Get started with 8'x9' shear wall, big guy.
The T shape: we connect two 4'  long T shapes together, but the cross-section of the connection is not flat,it makes the whole T shape look like bending. I will make it flat.

Sixth week

From Peng

To file

11/17/2011

Test 8

8*-4x9-OSB-54mil-2’over-8’up seam-cyclic

Pre-test

No over-drilling screw found for test 8. Just 2 fasteners at the bottom is too close the vertical seam, the previous ones was missed the flange of bottom track. re-drilling, too close.

Strap is good,no gap.

Vertical Seam is in the middle, looks fine.

The additional stud is 1’ over. Fastener spacing  is 12in.

After-test

43 circle reference displacement:1.988in.

 The peak is 3929lbs,displacement is3.329in.

The failure occurs at the horizontal seam and vertical seam connection area first, then the fasteners on the vertical seam on the south board pull through OSB.

The 2 fasteners on the 2’x8’ OSB without additional field stud side pull out first at the 38^th circle. Fasteners on that OSB in vertical seam fail at 41^st circle. Fasteners near the horizontal seam pulled through, others near the bottom wood bearing failure observed. The fasteners tilted observed at the bottom of middle field stud.(2’ to the bottom)

2 fasteners at bottom on the OSB without additional stud failed, one near the vertical seam pull through, the other is wood bearing failure.

Tear-out failure observed at the edge of the horizontal seam.

The additional field stud is fine, no fasteners fail observed.

Fasteners at bottom go through 2 layers steel(track and stud) often get cut off.

 A little lifting up of the shear wall during the test. I don’t know if it is the reason of the hold down or the anchor not tight enough. Will see next test.

Photos

Pretest

Aftertest

 We observed the piece of steel under the washer on the holddown bent a little bit during the test.

Sixth week

From Peng

To file

11/16/2011

Test 7 

7_4x9_OSB_54mil_8'up_1'over seam_cyclic

Pre-test

43 circles

Reference displacement:1.988in.

There are two fasteners on the seam location is over-drilling, I recorded.

The vertical seam seems a little gap. 0.052’’, but it is okay.

Additional field stud at 1’ over. The additional field stud is 600S162-54mil(33Ksi).

Fasteners on the Strap are good

Two fasteners on the vertical seam miss the flange of the additional stud. Re-drill

See how vertical seam behave..

After-test.

The peak is 3588lbs,displacement is 2.230in.

The failure occure at the vertical seam and the horizontal seam.

The fasteners on the 3'x8' board at the vertical seam pull out.

Horizontal seam, from vertical seam to north chord studs, the fasteners on the top boards pull out. From vertical seam to another side chord studs, the fastener on the seam is fine. The vertical seam failure near the 8’ high come first at 35^th circle and the it goes through the bottom and the horizontal seam breaks at 38^th circle observed.

The 1’x7’ OSB  good, no fasteners pulled out.

The middle and additional filed studs connection with track, bottom and top track flange buckle.

Bottom, just two fasteners at the 3’x8’ near the vertical seam is pull out, others are fine. 

Photos

Pretest

After test