span bridge
I think you probably mean "bridge span" rather than "spam bridge." A bridge span is the part of the bridge between its supports.
We may suggest 20ft (6m) to be the criteria but i insist this is practically too short. Bridge span of 20meters or less may be a good standpoint reference of "short span".
for short distance half circle bridge is better and for large span flat bridge is used.
A bridge's span is the length that crosses the gap.
The span is the distance between supports. The sum of the span lengths is the bridge length.
the span
its the span of a bridge for which the cost of building both substructure and superstructure is same....
A span of gap is something in a gas leak or under a bridge that smokes.
Tsurumi Tsubasa Bridge has a center span of 890m making it the largest bridge in the world!
Akashi-Kaikyo Bridge, Japan is the longest single span bridge which is 1,991 meters long.
Span is a verb, noun, and an adjective. verb - The new bridge will span the river. His acting career spanned 55 years. noun - I talked to him over a span of six years. Small children have a short attention span. adjective - Her apartment was always spick and span.
They are less likely to be hit by waves Short span beam bridges are very strong.