A dynamic blast wave traveled through solid rock at five thousand meters per second.
Sixty-two thousand tons of moving iron slammed into four heavy high-pressure pistons. Then, that force had to go somewhere.
If the foundation was weak, the shock would shear the entire granite cliff from its roots, sending wharves, cranes, and stone stonework tumbling into the southern deep pit.
Civil building was the science of finding bedrock and refusing to let go.
An unanchored structure suffered from overturning moments and pulling tension across its heel.
A dynamic level impact struck the crest of a pier. Then, the resultant force vector rotated downward through the foundation at a forty-five-degree slanted.
Without deep tie-backs, the pulling stress along the rear footing would exceed the shear capacity of the rock joints. It tore the cantilevered deck free.
By driving prestressed anchor tendons deep into the crushing zone of the mountain, the entire mass of Grey Crag was mobilized as a reaction balance weight.
