Seismic Design on the Fault Line: Engineering for the Serranía
The Mijas-Alpujata fault system runs beneath some of the Costa del Sol's most coveted plots. We examine the engineering responses keeping foundations stable.
By Editorial Team · Updated 06 OCT 2026
Seismic engineering strategies for fault-line construction
The Fault System
The Mijas-Alpujata fault extends roughly 40km from the Sierra de Mijas to the coast at Fuengirola, with active branches reaching into the Benahavís and Istan municipalities. While not classified as high-seismic by the national register, the fault produces periodic micro-tremors that compound differential settlement in structures founded on schist.
Base Isolation
Two of the five projects reviewed employ lead-rubber bearing isolators at the foundation interface. These systems decouple the superstructure from horizontal ground motion, reducing inter-storey drift by up to 70% in a design-level event. The remaining three projects use ductile reinforced concrete shear walls with capacity-designed coupling beams.
Earthquakes do not kill people. Buildings do. The fault line is a design parameter, not an obstacle.
Foundation Strategies
On schist substrate, deep micro-pile foundations anchored 8-12m below the weathered surface layer provide the most reliable load transfer. Shallow raft foundations on improved soil are viable where the schist is competent within 3m of grade.
“The daily record is where a place reveals its actual rhythm.”
Mistral & Marea · field note
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