Frequently asked questions

No. GPR is not X-ray. Ground Penetrating Radar uses low-power electromagnetic radio waves and receives reflected signals to map subsurface features from one accessible surface. It does not use ionising radiation, does not require radiation exclusion zones, and is generally suitable for occupied environments. X-ray (radiography) is a different method that uses ionising radiation and stricter safety controls.

A standard package includes site capture methodology, marked-up plans, identified reinforcement and post-tension risk zones, mapped service corridors where detectable, confidence zoning, and recommended verification hold points. For projects requiring model-based coordination, SiteOps can also provide CAD/BIM-ready overlays and data extracts aligned to the project grid and level set-out.

UPV does not directly measure compressive strength — it measures pulse velocity, which correlates with concrete quality. Strength estimation from UPV alone has an uncertainty of ±20–30%. SiteOps uses UPV as a quality indicator and uniformity mapping tool, always correlating with core test results for definitive strength assessment. The value of UPV is comparative — identifying which zones are weaker relative to other zones.

Yes. UPV is one of the most effective tools for post-fire assessment. Concrete exposed to temperatures above 300°C shows measurable reduction in pulse velocity due to internal microcracking and dehydration. By mapping UPV across fire-affected elements, SiteOps delineates the boundary between heat-damaged zones and unaffected zones. This mapping guides the extent of demolition and repair.

Thermography requires a temperature differential between the structure and its surroundings. Ideal conditions include clear skies, low wind (<15 km/h), and a period of solar heating or nocturnal cooling. In Southeast Queensland, early morning surveys (before 9am) or late afternoon (after 3pm) typically provide the best thermal contrast. SiteOps schedules surveys to coincide with optimal conditions.

IRT identifies areas of likely moisture presence through thermal anomalies, but it does not quantify moisture content. SiteOps uses thermography as a screening tool to identify zones of concern, then confirms findings with targeted invasive testing (moisture meters, core extraction) where necessary. This approach dramatically reduces the number of invasive test points required.

The number of cores depends on structure size, variability identified by NDT, and the testing objectives. Typical investigations require 6–15 cores across the structure. SiteOps uses GPR and UPV screening to identify critical locations, so fewer cores provide more representative data than random grid-based sampling. AS 3600 requires minimum three cores per assessment zone for strength determination.

Coring creates a cylindrical hole (typically 75mm diameter) that is repaired with high-strength structural grout immediately after extraction. The structural impact is negligible when cores are correctly located away from reinforcement. GPR and Ferroscan scanning at every proposed location ensures no reinforcement is cut during extraction.

Drones replace visual and thermal inspection for screening purposes — identifying where defects exist and their severity. However, physical testing (pull-off adhesion, coring, sounding) still requires scaffold or rope access at specific locations. SiteOps uses drone survey results to focus scaffold investment on the 10–30% of facade area that actually requires physical access, reducing scaffold costs by 60–80%.

Commercial drone operations are limited by sustained wind speeds above 38 km/h, rain, and reduced visibility (fog, heavy overcast). In Brisbane and Southeast Queensland, suitable flying conditions are available 85–90% of working days. SiteOps schedules drone surveys with flexibility for weather contingency — typically completing surveys within 1–2 days of the planned date.

Crack monitoring requires at least 12 months for one full seasonal thermal cycle — allowing the engineer to distinguish temperature-driven movement (cyclical) from progressive structural movement (trending). Settlement monitoring typically runs 6–24 months depending on the trigger. Long-term heritage monitoring may run indefinitely as part of ongoing asset management.

SiteOps sets thresholds based on structural analysis specific to each installation. For example, a tiltmeter alert might trigger at 0.1° (attention), 0.3° (warning), and 0.5° (alarm). A crack gauge might trigger at 0.3mm growth (attention) and 1.0mm (alarm). Thresholds are customised — there are no generic factory defaults. All alerts include the measured value, the threshold breached, and recommended action.

A comprehensive investigation is appropriate when the structural question cannot be answered by a single technology. Common triggers include: building purchase due diligence (need to understand full condition), visible deterioration on multiple elements (need to determine extent and cause), change of use assessment (need capacity verification), post-event assessment (need to determine damage extent), and asset management planning (need condition data for capital budgeting).

Site investigation typically requires 3–10 days depending on building size and complexity. Laboratory testing adds 7–14 business days. Report preparation and technical analysis requires 5–10 business days after laboratory results are received. A complete programme from brief to final report is typically 4–8 weeks. SiteOps offers expedited programmes (2–3 weeks) for urgent matters such as post-fire assessment or litigation timelines.

Yes. The majority of our heritage investigation programme uses non-contact or surface-contact techniques — GPR, LiDAR, UPV, thermography, visual inspection — that cause zero damage to original fabric. Where destructive testing (coring, mortar sampling) is required, it is minimised to the absolute minimum needed for technical certainty. Core locations are selected at concealed positions, and all penetrations are repaired with conservation-compatible materials.

This is the norm for heritage buildings, not the exception. SiteOps uses 3D LiDAR scanning to produce complete as-built documentation — floor plans, sections, elevations — from the physical structure. GPR and Ferroscan mapping determine internal reinforcement layout. This measured data provides the foundation for all structural analysis and capacity assessment.