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Masonry Wall Collapse

Quiz Questions

1. What type of wood was used for the diagonal bracing member?
CMU blocks
Southern Yellow Pine (SYP) OSHA scaffold plank
2. What was required by the contract documents for quality assurance during construction?
Independent testing company to perform site inspections and testing
Architect to perform periodic visual observations of the structure after construction.
Contractor to perform site inspections and testing
3. How many employees were killed during the collapse of the east wall?

One of the purpose of structural analysis was to determine whether the installation of the temporary bracings was properly done in accord with the applicable industry standards.


What was the maximum spacing of the control joints specified by the architect for the CMU walls?

40" on center
25’ on center
6 bracings
6. How could the incident have been prevented?
By reducing the lateral wind load on the wall.
By placing the rebar dowels correctly in the footing at the center of the wall.
By using stronger materials in the construction of the wall.
7. How many exterior braces were removed from the east wall prior to the collapse?
All three
8. What was the cause of the incident in the CMU wall?
The masonry did not gain adequate strength in 15 days.
The overturning moment due to lateral wind load was higher than the resisting moment induced by the self-weight of the CMU wall.
The dowel reinforcements were misplaced to the center of the wall.
9. What type of detail is shown in this figure?

masonry wall collapse

Beam column joint detail
Control joint detail
Bracing detail
All of the above
10. What caused the collapse of the east wall?
Human error
Strong winds
Heavy rain