波纹涵管衡水涵管 山西大同金属波纹管 山西陕西高速公路用涵管

波纹涵管衡水涵管 cross. In the future, the foundation of the bridge will also require the transportation of carrying beams. Because it is necessary to build temporary sidewalks and carry them improperly, sometimes the water flow in Hanoi has not stopped all year round, and the moving environment is difficult. When using a steel corrugated culvert, it is being poured into a sheet stone in Hanoi, and a 30cm gravel cushion is added. The side of the pipe and the top plat山西大同金属波纹管 山西陕西高速公路用涵管