由于我国有悠久的石拱桥桥梁建筑史,因之往往在公路选定路线时,特别是地方道路要考虑充分利用它。通过养护的长期观察,发现了一些问题,尤其是基础的保护问题。浙江宁波地区老石拱桥受当时施工条件限制,一般基础砌置不是很深,我们在不少水毁修复及残路上看到这个实际情况。当位于砾卵石河床上的桥梁,更因重复冲刷而桥孔下淘空最深,严重者即致坍塌。利用基础较浅、冲刷较甚的老石拱桥,加铺护底是比较有效的办法。我区某路有一座中型多孔石拱桥,高且长,在新辟公路时已经发现桥下有块石护底,但已残缺。经核定通过能力决定利用该桥时,根 As China has a long history of stone arch bridge construction, it is often the route selected in the road, especially in the local roads to consider making full use of it. Through the long-term observation of conservation, a number of problems have been identified, in particular the underlying protection issues. Old stone arch bridge in Ningbo, Zhejiang Province by the construction conditions at the time constraints, the general foundation is not very deep masonry, we have seen a lot of water damage repair and residual road to see the actual situation. When the bridge is located in the bed of gravel river, due to repeated scouring and the deepest under the bridge hole Amoy, that is caused by serious collapse. Use of the basis of shallow, more erosion of the old stone arch bridge, paving the bottom is more effective way. A certain area in our district has a medium-sized porous stone arch bridge, tall and long. It has been found under the bridge that there is a rock bottom, but it is incomplete. When approved by the approved capacity of the bridge, the root