Examples
Examples
Try the starting example
- Arch clear span (mm)
- 1200
- Circular segment rise (mm)
- 300
- Radial ring thickness (mm)
- 100
- Equal voussoir segments (count)
- 9
- Intrados circle radius (mm)
- 750
- Arch central angle (degrees)
- 106.260205
- Intrados chord per wedge (mm)
- 154.275905
- Extrados chord per wedge (mm)
- 174.846026
- Angle per wedge (degrees)
- 11.806689
Try another scenario
- Arch clear span (mm)
- 1200
- Circular segment rise (mm)
- 300
- Radial ring thickness (mm)
- 100
- Equal voussoir segments (count)
- 11
- Intrados circle radius (mm)
- 750
- Arch central angle (degrees)
- 106.260205
- Intrados chord per wedge (mm)
- 126.299634
- Extrados chord per wedge (mm)
- 143.139585
- Angle per wedge (degrees)
- 9.660019
Calculation method
Calculation method
Intrados circle radius (mm)
R=span²/(8×rise)+rise/2.
Arch central angle (degrees)
2×asin(span/(2R)) for minor segment.
Intrados chord per wedge (mm)
2R sin(angle/(2×segments)).
Extrados chord per wedge (mm)
2(R+thickness) sin(angle/(2×segments)).
Angle per wedge (degrees)
Central angle / segments.
Symbols and units
- a
- Arch clear span (mm)
- b
- Circular segment rise (mm)
- c
- Radial ring thickness (mm)
- d
- Equal voussoir segments (count)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- Idealized circular minor segment, 0<rise≤span/2, radial wedge sides, no mortar deductions. Geometry only; no arch structural assessment. Supported limits: Positive dimensions and integer 1–1000 segments; rise≤span/2.
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