一、概述桥梁是公路的重要组成部分。由于桥梁建筑技术性强、投资大,在经济和技术落后的旧中国,修建的公路桥梁甚少。新中国成立前夕,全国公路桥梁总长仅30余万米,其中永久式桥130余座。新中国诞生后,公路建设全面发展,随之新建和改建的桥梁,日益增多。 First, an overview of the bridge is an important part of the road. Due to the strong technical and investment of bridge construction, there are few highways and bridges built in old China with poor economy and technology. On the eve of the founding of New China, the total length of the country’s highway bridges was only 300,000 meters, of which 130 were permanent bridges. After the birth of New China, the road construction has developed in an all-round way. As a result, new and reconstructed bridges are on the rise.