Early Traffic Damage to a Fresh Pour Response

Purpose

The curing and protection SOP sets the barricade and posts the release dates that are supposed to prevent this. This procedure covers what happens the moment that barrier failed anyway, foot traffic, a pet, or a vehicle reached a slab before it earned the load, because the response has to be built on the slab's actual strength at the moment of contact, not on how many days have passed since the pour. Two days can mean very little strength gain in cold weather or most of it in warm; guessing from the calendar instead of the record is how a surface tolerance issue gets treated as nothing, or a real section failure gets skimmed over and handed to a customer who will find it again with a vehicle instead of a shoe.

Scope

Covers assessment and repair once unauthorized traffic has already contacted a curing slab before its posted release, for residential and light commercial flatwork, from discovery through repair close-out.

It does not cover the barricade, posted dates, and written traffic notice meant to prevent the intrusion, owned by the curing and protection after the pour SOP; the strength testing and release decision itself, owned by the test cylinder sampling and handling SOP; or a customer-reported crack found well after cure with no known intrusion event, owned by the customer disputes crack after cure response.

Roles and responsibilities

Procedure

1. Fix the elapsed time against the actual cure record, not a guess. Pull the finishing and cure log for that pour and compute hours or days between finishing and the intrusion, using witness accounts, footage, or the customer's report to bound the intrusion time as closely as possible. Acceptance: an elapsed-time figure recorded and cross-checked against the log rather than estimated on site. Wrong looks like assuming "it's been a few days, should be fine" without opening the record; stop rule, no severity judgment until the finishing time is confirmed. Hazard: none, a records check.

2. Pull the strength evidence for that pour before assuming anything about condition. Check whether cylinder breaks or a maturity reading exist for this slab and what they show at the step 1 elapsed time, per the test cylinder sampling and handling SOP. Acceptance: an actual strength value or documented specification age referenced, not an assumption based on typical timelines. Wrong looks like treating a slab as "probably fine by now" because a similar job usually is by this age, when this slab's own record may show otherwise; stop rule, no scope decision without checking whatever strength evidence exists for this pour. Hazard: none at this step.

3. Measure the damage, every affected point, before deciding what it means. Probe and measure any depression, rutting, or cracking at its deepest and widest points, photograph with a scale reference, and check for radiating cracks or displaced aggregate at each location, not just the one that looks worst. Acceptance: a measured depth at every point checked, against the shop's own working threshold of about 1/8 inch: at or under that with no cracking is a surface tolerance issue, deeper or accompanied by radiating cracks means the load broke bond or displaced material below the surface. Wrong looks like eyeballing one obvious rut as "not a big deal" and skipping the tape measure, exactly the shortcut that misses a second, less obvious mark with real cracking; stop rule, no cosmetic-versus-structural call without a measured number for every point. Hazard: probing concrete still under a wet cure carries the same alkaline contact risk as fresh work, so gloves stay on per the wet concrete skin contact SOP.

4. Re-secure the area before doing anything else. Barricade or re-barricade the damaged zone, and post a fresh, more visible traffic notice naming the actual release date, since a barrier that already failed once needs to be more obvious the second time. Acceptance: barrier up, notice posted and, where the responsible party is identifiable, acknowledged in writing again. Wrong looks like leaving the same faded barricade up on the theory the damage already happened so it no longer matters, which invites a second, larger intrusion into the same soft area; stop rule, no assessment proceeds in an area that is not currently secured. Hazard: none directly, though a barricade near an active repair zone stays clear of any doorway or work path.

5. Decide the repair scope against the measured extent, not the visible extent. Where the zone measured in step 3 is under roughly 10 percent of its panel's area and does not reach a joint, edge, or penetration, plan a local cut-and-patch; where it exceeds that, reaches a joint or edge, or the load appears to have disturbed the subgrade, plan a full panel saw-cut and replacement instead. Acceptance: a stated scope decision with the measured area, the panel area, and the percentage against the threshold, written down. Wrong looks like patching a zone that reaches a joint because a small patch seems cheaper, leaving a repair with no sound perimeter to bond into on one side; stop rule, any zone reaching a joint, edge, or showing subgrade disturbance goes to replacement regardless of its percentage. Hazard: saw-cutting either boundary generates respirable crystalline silica, so it runs under the silica dust control SOP's water-fed control.

6. On a local cut-and-patch, inspect the subgrade before you patch over it, and reopen the step 5 scope call if it disagrees with what step 5 assumed. Once the damaged concrete is cut out, check the exposed base for displacement, a void, or compaction loss under the load point, per the standard the pre-pour checklist and subgrade verification SOP sets. Step 5's scope decision was made on visible surface extent alone; if this inspection finds disturbance step 5 could not have seen from the top, the local-patch call is not final, it goes back to step 5's replacement trigger. Acceptance: base inspected, any disturbance within a normal recompaction corrected and re-compacted to the standard a fresh pour would require, photographed before the patch goes in; where disturbance exceeds that, the job re-routes to full panel saw-cut and replacement instead of patching over it. Wrong looks like patching directly over a base the load has already punched down because the cut-and-patch scope was already decided, reproducing the same depression once the patch itself takes traffic. Stop rule: no patch placed until the exposed base passes the same check a new pour would need, and any disturbance beyond normal recompaction stops the patch and escalates to full-panel replacement rather than proceeding on the step 5 call alone. Hazard: a cut-out pocket in sound slab is a trip and ankle hazard until backfilled, so it is flagged and lit across more than one shift.

7. Place the repair and document who bears responsibility. Execute the patch or panel replacement per the crack injection and patch repair technique or standard replacement practice, then close the record naming whether the intrusion was the shop's own crew, a subcontractor's, or the customer's or GC's, with no dollar figure attached at this stage. Acceptance: repair placed and verified per its own technique's checks, responsibility determination written, customer told the finding before close-out. Wrong looks like repairing the damage and closing the ticket with no responsibility finding, leaving the next similar intrusion on the same job with no history to point to; stop rule, the record does not close without a stated finding, even "undetermined, no witness." Hazard: none beyond the placement technique's own hazards, already covered by the technique it routes to.

The record this produces

One intrusion record per occurrence. Fields: job and pour identifier, finishing and cure log reference, elapsed time from finish to intrusion, strength evidence checked and its value or specification age, measured depth and extent at every affected point with photographs, panel area and the percentage calculation, scope decision with its basis, subgrade inspection result where a cut-out occurred, repair technique used and its own verification result, and the responsibility finding.

It sits with the cure log for that pour. The PM reads it if the same job produces a second intrusion, since a barricade that failed twice on one site is a placement or signage problem, not bad luck. The office reads the responsibility finding before any conversation with the customer or GC about cost, so the shop is working from a written finding rather than an in-the-moment impression.

One pass, with a step that failed

An attached garage slab, 20 by 22 feet, 4 inch, poured two days prior. A framing crew on the same job drove a loaded material cart across the slab before its posted vehicle date. Step 1 pulled the cure log: finishing complete at a known time, giving an elapsed 48 hours to the reported intrusion, confirmed against the framing crew's own account. Step 2 checked strength evidence: no cylinder set existed for this ordinary residential slab, so specification age governs and the posted release date, not yet reached, stands as the controlling figure.

Step 3 is where the first pass failed. The crew leader's initial look at a single tire rut called it "shallow, not a big deal" and started toward step 5's patch decision without measuring it. The stop rule caught that. Measured properly, the rut ran about 4 feet long with a maximum depth of 3/16 inch, over the 1/8 inch threshold, and two hairline cracks about 4 to 6 inches long radiated from its deepest end, a finding the eyeball pass had missed entirely.

Step 4 re-barricaded the slab with a more visible notice and got the general contractor to acknowledge it in writing again. Step 5 ran the area calculation: the panel containing the damage measured 10 by 11 feet, 110 square feet, and the affected zone, rut plus crack extension, measured about 4 by 1.5 feet, 6 square feet, roughly 5.5 percent of the panel, under the 10 percent line and not reaching any joint or edge, so the local cut-and-patch path applied.

Step 6 cut out the damaged section to sound material beyond the cracks and found the base beneath the rut's deepest point had compacted down slightly under the cart's load; it was recompacted to the pre-pour checklist's standard before the patch went in. Step 7 placed a polymer-modified cementitious patch per the crack injection and patch repair technique, verified sound by a sounding check three days later, and closed the record with the finding that the intrusion was the framing subcontractor's, documented for the general contractor.

When the intrusion does not fit the usual case

The intrusion happened while the surface was still plastic, same-day footprints or paw prints within the original working window: this procedure does not apply, since the slab pour and finishing standard's own re-floating technique for a surface still under finish is the right response. The responsible party disputes the finding: the answer is the measured record from steps 1 through 3, and the customer disputes crack after cure response's intake pattern applies if it escalates. The element is structurally significant, a footing or load-bearing slab rather than ordinary flatwork: route to an engineer before any scope decision, regardless of how small the zone measures. No cure log exists for an older slab the crew is working on for an unrelated reason: treat strength as unknown and document that the evidence does not exist rather than assuming a safe age.

References

• The curing and protection after the pour SOP, in this library, for the barricade and traffic-notice standard this procedure responds to a failure of.
• The test cylinder sampling and handling SOP, for pulling actual strength evidence rather than assuming it from elapsed time.
• The pre-pour checklist and subgrade verification SOP, for the base standard a disturbed subgrade is restored to before patching.
• 29 CFR 1926.1153, respirable crystalline silica in construction, for saw-cutting the local zone or panel boundary.
• See related: the crack injection and patch repair technique, the slab pour and finishing standard, and the customer disputes crack after cure response.