Secant pile walls are constructed by drilling and installing overlapping reinforced concrete piles to form a continuous structural wall that provides groundwater cut-off. Tangent pile walls are constructed similar to secant walls, but the piles are flush to each other and do not offer the same degree of groundwater control.
Secant and tangent pile walls may be installed in a wide range of soil conditions, including cobbles and boulders, and be either temporary or permanent, depending on the project objective. They are well suited to tight, restricted sites that preclude large cranes or pile driving equipment.
- Excavation support
- Bulkhead support
- Slope stabilization
- Groundwater control
Both secant and tangent pile walls are drilled to design depth and concreted in a primary/secondary sequence. Where walls are installed for structural support, the design can incorporate reinforcement for additional wall stiffness. For tangent pile walls, every pile is reinforced. However, since secant pile wall intersect, reinforcement is only used in every secondary pile to avoid cutting into primary pile reinforcement during secondary pile construction.