INVERT ARCH LENGTH OF HORSE SHOE SHAPE TUNNEL

For calculating the invert arch length of horse shoe shape tunnel , most of the time we depend on Auto Cad, as well as various hectic calculations.

From my past experiences and as per knowledge, the short-cut calculation has been developed, called as CBS  FACTOR, the calculation has been shown below……..

INVERT ARCH LENGTH OF HORSE SHOE SHAPE TUNNEL =  d X CBS FACTOR

Where,

d = Dia. Of horse shoe shape tunnel

CBS FACTOR = 0.8481

From above formula, we can calculate Ivert Arch length instantly with simple multiplication.

For example….

For a 6mt. dia tunnel, the Arch length has been calculated…

Invert Arch length = d x 0.8481

             6 x 0.8481 ->   5.0886 m

The above calculation can be verified using Auto-Cad or any mathematical technique