Research on Construction Technology of Metal Corrugated Culvert (Part 2)

(2) Material requirements for backfilling on both sides and top

Filling road foundation section, the structure is filled with gravel on both sides, the filling range is not less than 0.5 times of the structure pore size and not less than 0.5 meters, and the top filling range is not less than 0.5 meters. The requirements for backfill materials are the same as those for basic materials. Subgrade filling materials can be used outside the top and side filling range. In the foundation section of the excavation road, the structure is filled with gravel on both sides, the filling range is not less than 0.5 meters, and the top filling range is not less than 0.5 meters. The requirements for backfill materials are the same as those for basic materials. Subgrade filling materials can be used outside the top and side filling range.

(3) Foundation compaction and bearing capacity requirements

The foundation should be layered by vibrating compaction machinery. During rolling, the water content and compaction curve of the backfill material should be sprinkled and compacted, and the degree of compaction is not less than the specification requirements; when the height of the important project or roadbed is high (such as roadbed (The fill height is greater than 15 meters), it is necessary to make specific requirements for the foundation bearing capacity according to the specific situation. Corrugated culvert pipe on both sides and the top of the degree of compaction with the same level of subgrade compaction requirements.

(4) Other requirements

① When the metal corrugated culvert pipe is used in highway maintenance projects, the construction unit can only start to dismantle the old culvert after the culvert and the main parts of the opening are transported to the construction site. While dismantling the old culvert, grasp the basic materials The material preparation work is completed, and the excavation work can only be carried out after passing the inspection. When the metal corrugated culvert pipe is used in the construction of new highway projects, it is possible to grasp the preparation of the basic materials and the excavation of the foundation pit while ordering the culvert pipe.

②When the two sides of the culvert pass through the low-lying water accumulation zone, it is necessary to set up cofferdams and drain the accumulated water first, and if necessary, remove the part of the silt for replacement.

③ Import and export can be made of metal bellows joints made by manufacturers, there are two forms of straight pipes and slopes with the same slope as the roadbed slope; it can also be masonry masonry or dry masonry masonry according to the specific situation in the region . Generally in cold areas, metal bellows or dry masonry is used. Within a certain range of the entrance and exit grounds and slopes at the joint with the river bed, double-layer mortar masonry or dry masonry should be paved to prevent erosion and perform the necessary anti-seepage treatment; in order to prevent roadbed soil from blocking the culvert opening, at the opening and The embankment junction shall be protected by mortar masonry stone or dry masonry stone wall of a certain height and thickness (lead wire gabions may also be used).

④The entrance and exit of culverts with erosion should be set up with corresponding regulating structures as needed, and the entrance of the culvert should be treated as necessary according to the terrain conditions to prevent the erosion of the entrance of the culvert and affect the drainage capacity of the culvert.