springing line

noun

, Architecture.

1. a horizontal line between the springs of an arch or dome.
2. the rise or the angle of the rise of an arch.

Example Sentences

By its means the concave compartments are set slightly back from the octagon's inner face, leaving, at the springing line, portions of the wall-head to appear as little flat ledges on each side of the angles.

From Project Gutenberg

In San Vitale a considerable walling is built between the line of the octagon and the springing line of the dome, while the bed for the dome is formed by introducing, in the space over the angles of the octagon, niches which are worked above to the circle on plan.

From Project Gutenberg

This form carried the concrete from about 2 ft. below to about 2 ft. above the springing line.

From Project Gutenberg

Before this mortar had set, concrete was rammed in between it and the sheeting to a height of 18 ins. above the springing line, and then the remainder of the concrete placed without outside forms.

From Project Gutenberg

The lagging was first laid to a height of 3 ft. above the springing line on each side and the concrete dumped directly in place from runways laid on the lower chords of the arch ribs, which were placed 4 ft. apart.

From Project Gutenberg