Steel arch installed in an underground mine. Arches are employed to support
loads caused by changing ground movement or faulted and fractured rock. They
are designed so that when the ground load exceeds the design load of the arch
as installed, yielding takes place in the joint of the arch, permitting the
overburden to settle into a natural arch of its own, thus tending to bring all
forces into equilibrium. Lewis
Source:
Dictionary of Mining, Mineral, and Related Terms
