Void, honeycombing and delamination mapping

Air filled voids produce a reflection of opposite polarity to a water or grout filled one. Water, grout and steel invert the reflected wavelet; air does not. That sign is what separates a filled anomaly from an empty one, and it is discarded by amplitude only displays. Voids smaller than the pulse can resolve at that depth will not be detected, and this limit is stated in the report rather than left implicit.

Delamination gives a signature that can be looked for directly: a flat echo with air type polarity, ringing repeats at even intervals, and loss of the bar response beneath it. Depth slices at and just below the reinforcement level turn those signs into continuous areas in plan rather than scattered bright spots, which is what makes the extent something you can mark up, price and act on.

Submerged, tidal and splash zone elements, chloride contaminated concrete and heavily congested reinforcement are exactly where most GPR surveys fail outright. Chloride in the pore solution drives conductivity up and absorbs the pulse; high free water content drives the dielectric constant up and displaces every depth reading. Both effects are handled by parameters derived per exposure zone rather than per structure, and we say upfront whether a usable result is realistic on your element, before anyone commissions the work.

The HILTI PS 1000 X-Scan is a three antenna ground penetrating radar system that produces plan view images of concrete, not the single line trace of a covermeter or a rebar scanner. It records a 600 by 600 mm image scan grid in a single set up, extendable to 1200 mm by 1200 mm for larger elements, and detects to a stated maximum of 300 mm in concrete. Default settings assume dry, ordinary concrete, so we acquire in expert mode with the phase of the signal preserved and calibrate the dielectric constant on the element in front of us, processed in PROFIS Detection together with our own MATLAB routines.

Enquiry. Send the element type, thickness, exposure condition and what you need to locate on WhatsApp. Photographs, drawings and any previous scan output help us assess it fast.

Plan. We check access, moisture, exposure and reinforcement congestion against your target, confirm radar is the right test, and schedule the visit.

Scan and mark. Calibrated on the element, scanned in an orthogonal grid, and marked directly on the surface for your coring or cutting crew, same visit.

Report, if needed. Depth slices, plan extents and permissible core diameters, issued as a written report when your project requires formal documentation.