New British Geological Survey mapping of the upper 2m of seabed across the UK North Sea shows highly variable near-surface geology, challenging assumptions of relatively uniform sands used in many cable burial designs. The work identifies rapid lateral changes between sands, gravels, soft sediments and lag deposits at scales relevant to ploughs and jetting tools, with implications for trench stability, target burial depths and pull-out resistance for subsea power and telecoms cables. Designers may need denser geophysical and geotechnical sampling and more adaptable burial equipment specifications.

Helical piles and anchors are presented as displacement deep foundations whose performance depends on correctly specifying helix geometry (diameter, pitch, spacing), shaft type (solid square vs hollow round), and corrosion protection for the design life. The guide stresses matching installation torque to required axial capacity, using torque correlation factors (Kt) appropriate to soil type, and defining minimum embedment depth and number of helices rather than leaving these to contractors. Engineers are urged to state load cases (tension, compression, lateral), serviceability criteria, and testing requirements such as proof and pre-production load tests.

Contractors McIlwain Civil Engineering and SEE Civil Joint Venture have secured the next stage of early works for Queensland’s Mooloolah River Interchange, a key connection for the Sunshine Motorway and Nicklin Way on the Sunshine Coast. The package centres on large-scale earthworks and embankment construction to build up formation levels and stabilise ground conditions ahead of the full interchange upgrade. Geotechnical focus will be on settlement control and embankment performance in a coastal, flood-prone corridor before major bridge and traffic-switching works proceed.