pieux

Pieux, in English known as piles, are slender structural elements used to transfer loads from a building or structure to deeper, more stable soils or rock. They are employed when shallow foundations are inadequate due to weak surface soils, high loads, or adverse groundwater conditions. Piles can carry load by end bearing on a hard stratum or by shaft friction along their length, or a combination of both. They are manufactured from timber, steel, reinforced concrete, or composite materials and come in various shapes and sizes.

The main categories are end-bearing piles, which derive most of their capacity from contact with a deeper bearing layer, and friction piles, which rely on skin friction along the shaft. Construction methods include driven piles, which are hammered or vibrated into the ground, and cast-in-place or bored piles, formed by drilling a borehole and filling it with concrete. Micro-piles and drilled shafts are smaller-diameter variants used in constrained spaces or for seismic or renovation projects.

Design and testing focus on estimating ultimate capacity, serviceability, and group effects when multiple piles share load. Verification often involves static or dynamic load tests and non-destructive integrity testing. Piles are commonly used for building foundations, bridges, towers, offshore platforms, and waterfront structures, especially where soils near the surface are unreliable.

Maintenance considerations include protection against timber decay, steel corrosion, and scour or frost effects, as well as ensuring proper detailing at connections and pile heads.