The length of the sagged cable can be calculated as The angles between resulting and horizontal forces in support 1 and 2 can be calculated as The resulting support forces can be calculated as The horizontal support forces can be calculated as S = s a + s b (2j) Example - Inclined Cable with Uniform Load, SI unitsĪ cable with span 30 m, length a = 7.2 m, length b = 22.8 m, sag h 1= 1 m and sag h 2 = 10 m has a uniform load of 4 kN/m. The length of the sagged cable can be estimated as The angles between the horizontal and resulting forces can be calculated as and the vertical forces at support 1 and 2 can be calculated as If b > a the maximum forces in the cable and at support 1 and 2 can be calculated as The horizontal support forces in x-direction can be calculated as The parable equation estimated below can be used to replicate the shape in spreadsheets or CAD systems. The calculator is based on an iterative algorithm where the parable shaped cable is adapted to span L, height h 1 and h 2 according the figure above. The calculator below can be used for cables with inclined chords and uniformly loads. Inclined Cable Calculator - with Uniform Horizontal Loads Uniformly Loaded Cables with Inclined Chords The length of the sagged cable can be estimated to The sagging can be calculated by modifying eq.1 to The horizontal forces in the supports can be calculated as The vertical forces in the supports can be calculated as = 38.9 m Example - Known Tension at the Supports - Calculate Sagging and Length of Cableįor a 30 m long cable with uniform load 4 kN/m the resulting tension in the cable at the end supports are 100 kN. The resultant force acting in the supports can be calculated as The vertical support forces can be calculated as The horizontal supports and mid-span cable forces can be calculated as = 124 ft Example - Uniform Cable Load, SI unitsĪ cable with length 30 m and a sag 10 m has a uniform load of 4 kN/m. The resultant forces acting in the supports can be calculated as The vertical forces at the supports can be calculated as S (m, ft): Example - Uniform Cable Load, Imperial unitsĪ cable with length 100 ft and a sag 30 ft has a uniform load 850 lb/ft. Uniformly Loaded Cables with Horizontal Loads - Calculator Note that the equation is not valid when h > L / 4. The length of the sagged cable can be approximated to R 1,2 = resultant force at the support (lb, N) The resultant forces acting in the end supports - and in the direction of the cable close to the supports - can be calculated as R 1y = R 2y = vertical support forces (lb, N) The vertical support forces at the end of the cable can be calculated as Q = unit load ( weight) on the cable (lb/ft, N/m) R 1x = R 2x = horizontal support forces (lb, N) (equal to midspan lowest point tension in cable) The cable follows the shape of a parable and the horizontal support forces can be calculated as

Uniformly Loaded Cables with Horizontal Loads The equations below can also be used for cables only loaded with their own weight as long as the sagging height (h) vs.

Dynamic load calculator