25 January 2005
Figure B-5 Peripheral Tie Detail for Corner Columns
Horizontal Ties to External Columns and Walls.
In SI units, the equation for horizontal tie forces to external columns and walls
a) the lesser of 2.0 Ft or (ls/2.5) Ft
b) 3% of the largest factored vertical load carried by the
column or wall at that level
= the floor to floor height (m).
The justification for these values appears to be engineering judgment as to the forces
that are required to keep a column or wall vertical (i.e., minimizing the possibility of a
large P-∆ effect). Note that the second portion of requirement a) is scaled by the floor
to floor height, to account for larger story heights; 2.5 m was a typical British floor
As stated in the UFC, each column and each load-bearing wall must be tied
continuously from the lowest to the highest level. The tie must have a required strength
in tension equal to the maximum factored sum of the Dead and Live Load received by