Chapter 8 Section 2 The Most Famous Stone Girder Bridge

Wan'an Bridge, also known as Luoyang Bridge, is the most famous large stone girder bridge in ancient my country.The bridge was built in April of the fifth year of Huangyou (May 1053 AD) in the Song Dynasty and completed in December of the fourth year of Jiayou (January 1060 AD). It was presided over by Cai Xiang, the prefect of Quanzhou in the Song Dynasty. Luoyang Bridge was built at the mouth of the Luoyang River 20 miles east of Quanzhou City.According to the "Wan'an Bridge Records" written by Cai Xiang, the bridge "is built in the Yuan, with forty-seven lines of water [shishi], and the beams are empty. It is 3,600 feet long and 3,000 feet wide. Five feet. The wings are as many as the length of the railing, and the money is 14 million. If you ask for help, cross the Shizhi Sea, go to the boat and go alone. It is easy to be safe, and the people will not be disadvantaged."It can be seen that the Luoyang Bridge has a relatively large scale, and it has played a great role in connecting the official roads from Quanzhou Port to Fuzhou and the capital, and even promoting economic and cultural development.The bridge has been repaired and rebuilt many times.The existing Luoyang Bridge was rebuilt in the 26th year of Qianlong in the Qing Dynasty (AD 1761).There is a bridge embankment at the north end of the bridge, and the bridge is connected by the embankment. There are 40 holes.The whole bridge has 47 holes and is 540 meters long.If the embankments at both ends are included, the total length of the bridge is 834 meters.There are seven granite beams in each hole of the bridge, each beam is about 50 centimeters high, 60 centimeters wide and 11 meters long.Both sides of the bridge deck are protected by stone railings, with 500 stone pillars, and the length of the stone railings is the same as the length of the bridge.But the railings and stone pillars are now incomplete.The pier masonry is quite huge, and the two ends are built into pointed shapes to divide the water potential.In addition, there are 28 stone lions, seven stone pavilions and nine stone pagodas. In 1932, a low pier was added to each original pier, and a reinforced concrete slab was placed on it to pass cars.But the original stone beam is still in place.

The initial construction of Luoyang Bridge was very difficult.Here is on the verge of the bay, the river is wide, the water is fast-flowing, and there are occasional storms. sinister.Before the bridge was built, people used ferries to travel here and there, and boat capsizing accidents often occurred.In order to pray for a safe transition, the ferry here was named Wan'an Ferry, so after the bridge was completed, it was also named Wan'an Bridge. It was also named Luoyang Bridge because it was built on the Luoyang River.Luoyang Bridge has many innovations in bridge construction technology and craftsmanship, mainly in the following aspects:

First, Luoyang Bridge pioneered the raft foundation.Due to the dangerous water potential, the traditional piling technique could not be used for the bridge foundation, so a new method was found and a new foundation-laying technique was created.Architects and bridge builders in the Song Dynasty took advantage of the time of ebb tide to load large stones into the bottom of the water along the predetermined bridge route, forming an underwater stone embankment as the bridge foundation.According to investigations, the bridge base of Luoyang Bridge is more than 500 meters long and 25 meters wide.This is a major innovation in the history of bridge technology.

Second, Luoyang Bridge has applied and developed wedge-shaped piers.Spike-shaped piers appeared in the Tang Dynasty and were built at the end facing the direction of the water flow.For Luoyang Bridge, both ends of the pier are built in a wedge shape, which not only separates the impact force of the upstream river flow, but also separates the impact force of the downstream tide, achieving the purpose of reducing resistance and protecting the pier. Third, the Luoyang Bridge used the tides to float and erect stone beams.The large stone beams on the bridge deck in Luoyang weigh tens of tons. It is very difficult to erect such heavy stone beams suspended above the water in the absence of large lifting equipment in ancient times.But the bridge workers in the Song Dynasty solved this problem skillfully.They took advantage of the water drop of the tide to carry the stone girder between the two bridge piers by boat when the tide was high, and fixed it above the position to be placed. erection work.

Fourth, Luoyang Bridge uses oyster glue to strengthen the piers.It is almost impossible to connect the stones on the piers together in ancient times without quick-setting cement.However, when Luoyang Bridge was built, it cleverly used the growth characteristics of oysters to magically solve this problem.Oyster, also known as oyster, commonly known as sea oyster, is a scale marine animal.It grows and reproduces by attaching to other objects, and the calcareous shell also forms continuous sheets as it grows and reproduces, and is firmly cemented with the attachments.When the Luoyang Bridge was built, this feature was used to raise oysters on the piers, and the stones on the piers were cemented together to form a solid whole to prevent them from being washed away and improve the firmness and durability of the piers.This approach can be regarded as an outstanding scientific invention.In order to protect the bridge foundation and piers, it is forbidden to collect oysters within the scope of the bridge mark.This became a law locally and has been used throughout the ages.

The entire Luoyang Bridge is built with locally produced granite. "Flying beams across the sea, west and east", is magnificent and majestic.After it was completed, it became an important channel for the transportation between Quanzhou and the inland. People migrated by boat, and they were safe when they were in danger. Therefore, Luoyang Bridge has the reputation of "Wan An Ji Zhong".Under the influence of the completion of Luoyang Bridge, there was a wave of bridge construction in Fujian, especially in southern Fujian, and dozens of large and medium-sized stone girder bridges were built successively.