Anji Bridge: An Ancient Arch Bridge Built with Natural Stones

Student's Name
Instructor's Name
Course
Date
Anji Bridge
Anji Bridge, also known as the Zhaouzhaou Bridge in Hebei province of China, is one of the ancient arch bridges still standing (Ziyang 2627). It is an example of an arch bridge constructed using masonry stones that help sustain compressive forces. According to historical records, the bridge has encountered numerous catastrophic experiences, including eight wars, ten floods, and many earthquakes; however, it still remains intact (Mou et al. 748). It was built over 1400 years ago and is currently used as a pedestrian crossing (Ziyang 2628). It is the first open shoulder bridge that can reduce bearing deformation of the main arch bridge and increase stability. Anji bridge was built with natural stones. As a result, it has been strong and durable over many years (Mou et al. 748).
The bridge has two open spandrels on the sides, which allow a greater passage of floodwater; this has enhanced the bridge stability and prevented flooding compared to a closed-spandrel (Hua et al. 20). According to analysis, the open-spandrel shows flexibility by reducing the bridge's weight and increasing the drainage surface area by 16.5 percent, reducing flood forces on the bridge (Mou et al. 748). It demonstrated good anti-seismic properties. Construction using closed-spandrel, on the other hand, showed a deflection of the compression line from the axis hence choosing the former.
Anji Bridge was constructed using 28 thin curved limestone slabs, assembled with iron tenons to allow the rise and fall while supporting the abutments and preventing a collapse in case the arch breaks. The 28 vertical thin slabs are positioned longitudinally; they support the arch by adjusting shifts preventing the bridge from collapsing (Mou et al. 748). The arch around the springing bottom is broad compared to the top section; this increases the lateral stability when the bridge's width reduces from the bottom to the top. In addition, the transverse rigidity of the bridge was improved using five iron tension rods.
The bridge skewbacks foundations were constructed with five courses of stone each and are embedded in alluvial deposits of firm light loam and clay with the ability to withstand the load of the bridge (Mou et al. 748). The arch foot is joined to iron anchors to prevent its displacement, and the addition of wooden stakes was done to prevent vertical settlement as well (Liu et al. 21). Furthermore, protective walls were built around the abutment to protect it from being carried away during floods. During construction, falsework used to support the process after being removed was added with on the arc for stability purposes. In addition, the process is done symmetrically for the structure to maintain its equilibrium.
The bridge, over the years, has experienced many earthquakes and managed to stay intact. In 1996, an earthquake with a magnitude of 7.6 hit Xingati city 2.5 miles from the bridge, but the bridge showed excellent seismic performance (Hua et al. 20). An analysis was carried out using three-d...