在丰产石料的山区,直接使用石料修建盖版涵洞,是最简便而迅速的方法。但原有石盖版涵洞标准图中规定了石盖版涵洞最大跨度为1公尺,盖版最小厚度不小于25公分。这样不但大大地限制了这种桥涵的广泛使用,且在材料的选备上造成一定的困难。而在地方道路修建上已有的经验证明,可以大大地超越这个限度,有 In the boulder production area, the direct use of stone to build covered culverts, is the most simple and rapid method. However, the original stone cover version of the culvert standard map provides a maximum cover of culvert version of the span of 1 meter, cover the minimum thickness of not less than 25 cm. This not only greatly limits the extensive use of such bridges and culverts, and in the material preparation caused some difficulties. The experience gained in the construction of local roads proves that this limit can be greatly exceeded and there is