在砌筑较大跨径的石拱桥时,如何制造一种理想的拱架,正是目前寻求解决的一个问题。1959年9月,甘肃甘南交管局桥梁工地,曾试制了一种土、木结构的拱架。现在将有关资料介绍如下: 桥梁的一般情况这是一座单孔20.68米的石拱桥。载重汽—13级,桥面净宽6米,拱灭度为1/5,拱形采用等截面圆弧形,厚度1米,用双层粗料石砌成。并在大拱顶上纵横方向设置六个1.5米及四个1.0米的小拱。 (见封面照片) 当地条件对拱架的要求该桥跨过大夏河。当时河流的最低深度2.2米,主槽流速约每秒3米,河面宽23米,河底为大孤石夹砂砾层。因此。要搭设一般的木拱架就有困难,木桩打不进,木箱埋桩又会大量减少泄水面积,致使流速加快。会使木箱不稳定,易于被水冲走。同时一般的木拱架用的木料及铁件多,制作安装也比 How to make an ideal arch when building a large span stone arch bridge is precisely what we are looking for to solve. September 1959, Gannan Traffic Management Bureau of Gansu bridge site, had trial production of a soil, wood structure of the arch. Now the relevant information is as follows: The general situation of the bridge This is a single hole 20.68 meters stone arch bridge. Load -13 level, the bridge deck width of 6 meters, arch off degree of 1/5, arched cross-section arc with a thickness of 1 meter, with double coarse stone brick. And in the vertical direction of the big vault set six 1.5 m and four 1.0 m small arch. (See cover photo) Local conditions on the arch of the bridge across the Daxiahe. At that time, the lowest depth of the river was 2.2 meters, the main channel flow rate of about 3 meters per second, the river width of 23 meters, the bottom of the river for the large boulder sand gravel. therefore. To build a general wooden arches have difficulties, wooden blocks can not get into, wooden piles buried a substantial reduction in drainage area, resulting in faster flow rate. Will make the wooden box unstable, easy to be washed away by water. At the same time the general wooden arches with wood and iron pieces, production and installation than