The line of thrust is the locus of the points, through which forces pass in a retaining wall or an arch. It is the line, along which internal forces flow, , .

In a stone structure, the line of thrust is a theoretical line that through the structure represents the path of the resultants of the compressive forces, . For a structure to be stable, the line of thrust must lie entirely inside the structure, , .

Where important

The line of thrust is important in almost any architecture bearing weight. This includes aircraft, bridges, plus arches; see catenary arch.

An arch won't collapse, when the line of thrust is entirely internal to the arch, .

See also

• Damage tolerance
• Force lines
• Strength of materials
• Stress concentration
• Structural fracture mechanics
• Stress intensity factor
• Stress–strain analysis

External links

• One largish article, talks about line of thrust
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