Installationo Advise for Direct Buried Fiber Optic Cable
 

1 Depth of the cable should meet the requirements of Table 3.1.

Buried cable depth Table 3.1

Laying a lot or soil

Depth (m)

Remark

Normal soil (hard soil) ≥1.2

Half stone (gravel soil, wind fossils) ≥1.0

Full stone ≥0.8

Counting from the ditch advance plus 10 cm of fine soil above

Quicksand ≥0.8

Suburbs, towns and villages ≥1.2

Downtown sidewalks ≥1.0

Crossing the railway, highway ≥1.2

From the bottom of ballast or road

Ditch, canal, pond ≥1.2

Farmland drainage ditch (groove width of less than 1 meter)

≥0.8

3.2 Buried cable distance from other buildings and underground pipelines shall comply with the requirements.

3.3 the same ditch laying fiber optic cable, may not cross, overlap, respectively, should be adopted at the same time laying the traction mode.

3.4 Buried cable laying shall meet the following requirements:

Depth 1) shall comply with the provisions of the cable trench, the ditch should be smooth and no gravel; stone, stone semi-ditch should be paved 10 cm thick fine soil or sand;

2) mechanical traction, should be used to the pulley;

3) for manual lifting, the cable should not be less than the specified bending radius of curvature and mopping the floor, pulling tight and other phenomena;

4) the cable must be flat on the ditch, shall not vacated and arched;

5) fiber optic cable laid in slope greater than 20 °, when the slope grew up in the 30-meter slope, should adopt measures to "S" shape or design requirements laid process;

6) After the laying process or laying, cable jacket should be checked and, if damaged should be repaired immediately; check cable sheath after Buried cable laying the insulation resistance.

7) in the fiber optic cable and copper wire must confirm compliance with quality inspection acceptance criteria before the whole earth groove back.

3.5 cable trench backfill shall meet the following requirements:

1) First backfill 15 cm of fine soil pulverizer or prohibited will be stone, brick, and other permafrost pushed into the trench, and should be doing to overcome;

2) backfill should be 10 cm above the ground.

3.6 Buried cable design requirements and protective measures should meet the following requirements:

1) fiber optic cable across the railway line and not excavated road surface, taking top tube method. Top tube should be kept straight, pipe size and location should meet the design requirements, allowing a ground-breaking position can be taken to protect pipe, clogged nozzle should be done to protect the top tube or pipe buried.

2) optical fiber cable line crossing tractor road, the countryside and the city road, residential or easily groundbreaking lots, according to the design requirements of the construction method of protection. When the cable laying brick above, should cover 20 cm thick vertical pulverizer and then spread red brick, with two cable should cross the ditch laying brick shop.

3) optical fiber cable line through dredging and dredging has taken fertilizer ditch, canal, pond when, at the top of the cable should be covered cement board or cement sandbag protection.

4) fiber optic cable across 0.8 meters above (including 0.8 m included) Goukan, terraced slope should make, slope protection mode according to design requirements. In addition to the design of special requirements, generally we do not slope when crossing Goukan 0.8 m or less, but it must hierarchical compaction restitution.

5) fiber optic cable lines across the region should be required for termite activity termite treatment.

6) optical cable lightning protection measures must be handled according to the design requirements. When using lightning discharge flow lines, should be laid single or double root drain wire at the top of the cable 30 cm; when the backfill some reason they dug to re-lay the cable, you must strictly check the drain wire is located above the cable, strictly prohibited reversion phenomenon.

7) with a special section of flag laying shall meet the design requirements.

Set aside 3.7 cable connection points should be properly placed in the pit joints, sealing ends must be done to deal with moisture, prevent flooding or man-made damage to the cable.

3.8 mark stone buried cable line shall meet the following requirements:

1) fiber optic connectors, cable turning point, drain line start and end points, with the start and end point of the groove laying cable, fiber optic cable special reserved spot, and other cable crossover point, and downtown locations across the obstacle straight sections every 200 m , suburban and long-distance shall be provided every 250 meters ordinary standard stone.

2) need to be monitored within the metal sheath of the cable insulation, the joint shall be set up to monitor the potential point mark stone.

3) There are signs that can be used when available instead of fixing flag mark stone.

4) mark stone unearthed 40 cm depth of 60 cm, the soil should be compacted around the mark stone.

5) the general standard stone should be buried directly above the cable. Mark stone joints should be planted on the cable line route, marked with the word rock side should face the cable connector. Standard corner stone should be buried in the intersection of optical cable turn, angled cable mark stone toward smaller side. When laying the cable along the highway spaced not more than 100 meters can mark stone toward the highway.

6) mark stone with solid rock or reinforced concrete production, there are two specifications: the general area using a short mark stone, specifications should be 100 × 14 × 14 cm; soft soil and stone marked with a long ramp area, specifications for the 150 × 14 × 14 cm.

7) number for the white stone marked red (or black) paint in block letters, font correct, clean surfaces. Number should be based on the direction of transmission from A to B end end direction choreography. Generally hop is individually numbered units.