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Figure 117- Pre-Tensioned Front Tie with Floating Focal Point

CRITICAL ANGLE IN ANCHOR SYSTEMS
The connection of two or more anchor
points and a load is placed upon it forms
a critical angle (Figure 119). This interior

angle can act as a force multiplier. As the
angle increases, the force directed along
each anchor leg is increased. At 120°, the
force on each anchor leg is equal to the
load. Beyond this point, such as a
tensioned highline system, the force
applied to each leg of the anchor rapidly
increases.

CRITICAL ANGLES IN ANCHORS
Total amount of load (force) placed
Angle
on each anchor leg with a 1 kN load
0° 0.5
90° 0.7

120° 1
170° 5.7
179° 57.2 Figure 118- Critical interior angles
Source: Based upon NFPA 1670 (annex A) assocated with anchor rigging.

123 | P age