When the optical cable line passes through the sections that cannot be excavated, such as railways, highways and streets. Pipe jacking method should be adopted and protected by steel pipe or plastic pipe. Usually, this protection measure has been taken before cable laying. When the optical cable is put in, the plastic semi-rigid pipe should be put in the steel pipe first, and then the optical cable should be put in. The nozzle should be blocked with oil hemp or other materials.

For the crossing protection of simple roads or rural roads, cement cover plates or red bricks are generally used to protect optical cables. When brick protection is adopted, firstly, 20cm thick broken soil is covered above the optical cable, and then red bricks are laid vertically. When laying two optical cables in the same ditch, red bricks should be laid horizontally for protection.

Matters needing attention in laying directly buried optical cable

1. When bending optical cables, the minimum bending radius cannot be exceeded.

2. The traction of laying optical cable shall not exceed the maximum laying tension. At the same time, excessive external force (lateral pressure, impact, bending, torsion, etc. ) should be avoided.

3. Strictly trained technicians should terminate and maintain optical fibers. When optical cable is applied to trunk lines, at least 6-core optical cable shall be used in each wiring room, and 12-core optical cable shall be used for advanced applications.