A developer broke ground on a seafront apartment block off Marine Parade last year. The boreholes said competent chalk at 4 metres. The piling rig hit a soft, putty-like layer at 5.5 metres and the casing nearly collapsed. Three days of delays and a revised foundation scheme later, the contractor brought us in to run a CPT profile across the site. Brighton’s geology is deceptive. The White Chalk Subgroup dips beneath variable Head deposits, Coombe Rock and raised beach shingle, and the transition zones are rarely uniform. We run the cone penetration test to map those transitions precisely, giving engineers continuous resistance data that borehole logs cannot capture on their own. For deep foundations near the seafront or basement excavations in the North Laine area, CPT results clarify the real stratigraphy before steel goes in the ground.
Continuous cone resistance data catches the soft seams that boreholes miss, and on Brighton's chalk those seams change the foundation design completely.
