615.1 Duct materials & sizes

Specify HDPE/PVC diameters per cable mix (515). Right ducts protect HVM bollard wiring.

Choose HDPE or PVC conduit grades that match the pull length, expected EMC exposure, and site environment (buried vs. exposed). For automatic bollards, reserve larger bores for power and smaller for control/loops per 515 Cables & Routing. Where multiple circuits share a route, use a bundled duct bank with dedicated sleeves to maintain segregation and simplify maintenance.

Typical planning starts from the cable schedule: sum outside diameters with a 40–50% fill limit, then round up to the next standard size to reduce pulling friction. Allow one empty sleeve for future fiber or sensors in every critical lane set. Where vandalism or vehicular loading is likely, consider higher crush-strength ducts and concrete encasement per 934 Ducting & Trench Details.

615.2 Depth, cover & separation

Meet cover minima and segregate power/control (347). Separation preserves crash rated bollard signals.

Set trench depth to meet local utility cover minima and to pass beneath paving base layers without creating ponding edges. Keep power and control in separate sleeves; add horizontal separation or a divider within a bank to limit coupling and simplify fault finding. Maintain a consistent datum so future digs can safely locate routes from surface levels and benchmarks.

In mixed corridors (lighting, CCTV, access control), place high-voltage lowest, then power, then controls at the top of the stack. Use detectable marker tape and route boards at changes of direction. Confirm offsets at crossings to avoid clashes flagged during 240 Utilities / Surveys.

615.3 Entry/exit elevations

Maintain falls away from enclosures (334). Elevations keep HVM bollard pits dry.

Introduce a subtle fall away from bollard enclosures and chambers so water migrates to sumps rather than into terminations. Add a drip loop before any gland plate and keep entry holes above the designed waterline. Where groundwater risk exists, coordinate with 614 Dewatering & Groundwater and consider raised cable glands.

615.4 Bends & pull boxes

Limit bends; place draw pits by run length. Good geometry eases crash rated bollard pulls.

Keep to long-radius bends and minimize total bend count per run (e.g., “two 45° instead of one tight 90°”). Space draw pits so each segment respects pulling tension and sidewall pressure limits—check manufacturer tables and the cable’s allowable tension. Avoid back-to-back bends between pits. Where a 90° turn is unavoidable, use a pit at the corner and a long-sweep bend on exit.

Size pits for safe ergonomics: lid clear opening, working depth, and maintainable separation of power/control splices. In high-water areas, design pits with buoyancy checks and drainage paths to the site sump network.

615.5 Glanding & sealing

Use IP-rated glands and seals (516, 245). Sealing protects HVM bollard terminations.

Choose the entry method first: gland plate vs. direct gland, then specify IP/NEMA to match exposure and dewatering performance. Use compression or barrier glands appropriate to cable type; for multi-core looms, add strain relief anchors inside the box. Seal spare knockouts and sleeve-to-wall annuli using compatible modular seals to prevent silt ingress defined in your drainage strategy.

615.6 Identification & color codes

Adopt color sleeves and route tags (527). IDs speed crash rated bollard maintenance.

Apply a simple scheme: sleeve color or printed tape for power vs. control, ferruled core IDs at terminations, and durable pit labels tied to an asset register. Use route tags at pit entries and at 20–30 m intervals along corridors. Match all labels to the cable schedule and 732 Asset Register & Serials.

615.7 Spare ducts policy

Install spares for future upgrades (446). Spares reduce HVM bollard downtime.

Provide at least one spare sleeve in every lane set and one per major cross-site corridor. Cap and label spares at both ends, keep them out of flooded zones, and include them in the 731 As-Built Drawings. Spares enable later additions (e.g., counters, health pings) with minimal disruption.

615.8 Pressure/water tests

Test ducts before cable pulls. Tests prevent crash rated bollard rework (714).

Before pulling, run a brush and mandrel through each sleeve and record pass/fail—see mandrel test. Where specified, perform low-pressure air or water tests to confirm integrity of joints and seals. Any failure is cheaper to fix pre-pull than after terminations. Log results in the ITP with pit IDs and coordinates, then proceed with measured lubricant and controlled winch tension.

615.9 As-built updates

Record routes, depths, and pit IDs (731). As-builts support HVM bollard SAT (638).

Capture final routes, depths/cover, pit chainages, and gland references. Update the cable schedule, route drawings, and GIS layers for retrieval. Add geo-tagged photos at key pits and crossings, and cross-reference to the 937 Photo/Redline Logbook. Solid documentation accelerates SAT retests and future fault finding.

615 Ducting & Draw Pits — FAQ