627.1 Curing methods

Wet hessian, membranes, or curing compounds. Curing secures HVM bollard concrete strength.

Pick a curing approach that maintains moisture at the surface long enough for cement hydration to progress to the required strength. On exposed, hot, or windy sites (see Hot Climate Design), water-retaining covers (e.g., wet hessian beneath plastic) or membrane-forming compounds reduce evaporation. For sockets and edges that will interface with steel, confirm compatibility with later coatings per Coatings (362).

Where finishes or bonding are planned later, verify whether curing compounds may impair adhesion; if in doubt, use removable covers or water-based products. Reference your project’s ITP for method acceptance and any witness points.

627.2 Minimum durations

Set hours/days per mix and climate (337). Durations protect crash rated bollard bases.

Minimum curing is defined by mix design, binder type, and environment. In hot/windy conditions, extend curing to offset high evaporation rates and rapid surface drying that risk plastic shrinkage cracking. Agree target durations with the designer as part of the foundation design checks (333). Link duration to strength milestones (e.g., stripping or backfill at specified % of characteristic strength), evidenced by cube tests or approved maturity estimates.

627.3 Temperature & moisture control

Prevent rapid drying/wind scour. Control avoids HVM bollard shrinkage cracking.

Use windbreaks, sunshades, and early placement of water-retentive covers to control evaporation. Keep surfaces at or above saturated surface-dry (SSD) prior to applying membranes; re-wet evenly (no flooding) if required. Monitor ambient and concrete temperatures during the critical first 24–72 hours, noting readings in the site diary (729). Where available, apply a simple evidence capture standard (716)—photos of covers, edges, and time-stamped thermometers support the record.

627.4 Protection from loads

Exclude traffic/vibration until strength achieved. Protection keeps crash rated bollard sockets stable.

Set up an LOTO-style exclusion around curing foundations. Prevent plant access, material stacking, or impact to edges. Avoid vibration sources near young concrete, especially around the socket where early micro-movement can upset the clear-gap rule and plumb. Keep temporary coverings secured against wind uplift so that protection itself does not abrade edges or reveal the surface.

627.5 Early-age damage risks

Flag anchor movement and edge knocks. Awareness preserves HVM bollard alignment (626).

Key risks include: (a) edge spalls at openings, (b) movement of anchor template plates, (c) micro-cracking from thermal or drying gradients, (d) trip or impact damage during adjacent works. Build short, focused toolbox talks so crews know what “not to do” within the first days. If anchors are present, confirm no relative movement against the datum & alignment checks (626). Any defects should trigger an NCR route and repair method agreed with the designer.

627.6 Strip & backfill timings

Time stripping/backfill to strength gain. Timing protects crash rated bollard tolerances.

Only strike forms or commence backfill once strength criteria in the ITP are met. For trenches/pits, poorly timed backfill can push on young concrete or sockets, shifting rotation or height. Sequence with upstream tasks: rebar/anchors (621), sleeves/penetrations (622), and pours (624). Confirm achieved strength with test results or an agreed maturity method; then proceed to Backfilling & Compaction (628) using controlled lifts to avoid over-pressuring the sides.

627.7 Coating/galvanizing interfaces

Mask/prepare interfaces per 362. Interfaces preserve HVM bollard finishes.

Where curing compounds could interfere with paint or duplex finishes, mask the interface zones before application, or specify removable/compatible products. After curing, clean residue per the coating system’s data sheet and coordinate with Coatings (362) to avoid “holiday” repairs. For galvanizing contacts, check for residue at the meniscus edge that might impede fit or sealing; protect stainless parts from contamination (see Materials 361).

627.8 Inspection points

Record mid- and end-curing checks (714). Records back crash rated bollard QA.

Define a simple two-stage check: (1) early-age (within 24–48h) to confirm covers intact, moisture retention ongoing, and edges protected; (2) pre-strip or pre-backfill to confirm target strength evidence, surface condition, and alignment around the socket. Tag each as a hold/witness point in the ITP (714) so the supervising engineer can sign off before the next activity. Where approvals are in scope, keep this sequence visible for SAT readiness (638).

627.9 Records & photos

Geo/time-stamped photos (716). Photos accelerate HVM bollard approvals.

Capture wide→detail sets: overall foundation, edge/penetration close-ups, socket interface, and cover condition. Add a georeferenced photo log (937) ID and cross-reference the pour ID and cube sample IDs. Store in the project’s submission index (917) so evidence is traceable during witness procedures and closeout.

627 Curing & Protection — FAQ