Physical principle of stone arch bridge

Stone arch bridge is one of the four basic configurations of traditional bridges in China, and there are two main physical principles related to it:

The arch structure of 1 can convert the vertical downward pressure on the stone arch bridge into the vertical pressure between the stones of the arch bridge.

The stone section of the stone arch bridge is close to trapezoid, and the upper bottom is larger than the lower bottom. At this time, the vertical downward pressure will be decomposed into oblique pressure on both sides, so the pressure will be transformed into direct pressure on the stone and transmitted to the bridge foundations on both sides along the arch. Therefore, as long as the stone arch bridge is not subjected to lateral force, the structure is very stable and will not fall down for thousands of years.

Arch structure can effectively alleviate the influence of thermal expansion and cold contraction, and can eliminate the slight influence of solid thermal expansion and cold contraction under a small amount of deformation of arch arc, while flat bridge must be relieved by expansion joints and other methods.