The rig arrives on a low-loader, a track-mounted drill with a mast that folds down for transport through Portlaoise's narrow approach roads. Once it's leveled on site, usually on a brownfield plot near the Triogue or a greenfield extension beyond the M7, the automatic hammer starts its rhythm: 63.5 kg dropping 760 mm, driving the split-spoon sampler into the ground in 150 mm increments. We record every blow. The N-value isn't just a number on a log sheet; it tells us whether we're in the dense glacial till left by the Midlandian glaciation or hitting the weathered limestone bedrock that underlies much of Portlaoise. Without this profile, you're guessing about bearing capacity.
An N-value from a calibrated automatic hammer in Portlaoise's glacial till gives you a number you can take straight into a bearing capacity equation and trust.
