Cracks in new concrete: record the condition and obtain qualified review
Fine cracks appear in the sawmill yard slab the morning after a windy placement. A different straight crack is noticed later. The foreman needs a useful record and a review route, rather than reassurance that the first pattern is 'normal'.
Record the crack's location, observed pattern, known timing and safely obtained measurements, then send the account through the project's qualified review route. Ask for direction on urgency, restrictions and any monitoring. Do not judge structural adequacy, cause or repair from width or a photograph alone. An issue that may be urgent must not wait a week merely so the record can include movement.
Make the observation useful to the reviewer
- Locate the crack precisely. Mark the element, grid or area on the current plan. Record where it starts, its observed direction and extent, and which faces are actually visible. Say when it was first noticed and what is unknown. Do not describe it as going through the element unless the available evidence establishes that observation.
- Record safe measurements and context. Use the measurement arrangement agreed with the appropriate competent people and retain its method and limits. Include located photographs, relevant pour and curing records, and known weather or loading information. Do not enter a restricted area, disturb the crack or remove finishes merely to improve the record.
- Use public descriptions as questions. Industry guidance describes several cracking mechanisms, including plastic shrinkage and effects associated with movement, restraint or settlement. These names can help organize questions for the engineer. They do not diagnose this crack, establish that it is harmless or prove which person's work caused it.
- Obtain direction and track changes. Send the record promptly to the appropriate reviewer and identify any immediate concern through the safety process. Follow the issued restrictions, monitoring and verification instructions. Record later observations with their real dates, keeping the first account. Qualified people decide the significance and any required response.
Keep the observation separate from the later finding. If a review names a cause or requires investigation, link that dated response instead of editing the first entry to imply the foreman knew it at discovery. A small crack can still require assessment for the actual use and assembly. Conversely, an alarming photograph is not a quantified engineering conclusion. Record what the responsible people decide and what remains unresolved.
Common mistakes
- Calling a pattern harmless before qualified assessment.
- Waiting a week despite a potentially urgent concern.
- Rewriting discovery notes with a cause identified later.
Checklist
Send a crack-review record
- Element, location and observed extent.
- Discovery date and known limits.
- Safe measurements, images and context.
- Qualified direction and any restrictions.
- Dated changes and linked review findings.
Check your understanding
The pattern resembles a public guide's shrinkage photograph. Does that settle its cause and significance?
