1. Tensile Capacity of Adhesive Anchors in Threaded Perforations
Hua Liu (PhD Student)
Yan Liu (Visiting Professor)
Leonardo Serrato (Undergraduate Student)
Yuchen Hui (MS Student)
Jian Zhao (Faculty Advisor)
University Of Wisconsin-Milwaukee

2. Adhesive anchor ceiling accident

3. Adhesive anchor failure

4. Defects found in Sasago Tunnel

5. Adhesive anchor system
Cleaning is critical

6. Hypothesis
Dusts in drilled hole weaken the adhesive-concrete interface.

7. Preliminary tests 8.9 9.0 5.6 Hole Condition: C - Clean U - Dusty
Interface:
S - Smooth
T - Threaded
D - Dry
W - Wet
CTD
CSW
UTD
8.0
8.9
2.0
CSD
CTW
USD

8. Creating threads in drilled holes

9. The drilled hole with threads

10. Concrete breakout Tension load Epoxy by adhesion and interlock

11. Failure mode change

12. Finite element analysis

13. Summary Dusts in drilled hole weaken the adhesive- concrete interface
Creating threads in drilled holes
The tunnels with concrete ceiling panels are safer

14. Thank you for your supports.
1. UWM Research Foundation 
2. UWM Prototyping Center
3. UWM The Advanced Analysis Facility
4. DeWalt

15. Question?