10-storey residential block
Lekki Phase 1 · 2024 · Confidential client
Project photos
Project overview
Ground conditions
The plot sits on low-lying, reclaimed ground typical of Lekki Phase 1. Boreholes found made ground and loose silty sand to about 6 m, soft clay with peat lenses to 14 m, then dense sand to the full 35 m depth. Groundwater stood about 1.5 m below ground level.
Challenge
The client planned a 10-storey reinforced concrete frame on a tight urban plot. The soft clay and peat could not carry a raft or pad foundations without large settlement, and the high water table ruled out a deep open excavation.
Solution
We drilled six cable-percussion boreholes to 35 m with an SPT every 1.5 m, took undisturbed samples in the clay, and ran 48 laboratory tests, including triaxial and oedometer tests on the soft layers. The interpretative report compared shallow and piled options.
Outcome
We recommended bored piles founded in the dense sand below 14 m, with design capacities and settlement estimates for the structural engineer. The report was delivered in six weeks, and the piling contractor used our logs to set pile toe levels.
SampleNarrative and figures are placeholder content.
Services used
Services on this project
Request a quote
Planning a build in Lagos? Start with the ground.
Tell us where the site is and what you plan to build. An engineer will come back with a proposed scope of investigation and a quote.