How do you construct a secant pile wall?
A Secant Piled Wall is a retaining wall constructed for ground retention prior to excavation. The wall is formed by constructing alternating primary (female) and secondary (male) piles where the secondary piles partially cut into either side of the primary piles in order to form a continuous impervious structure.
What is secant pile?
A secant pile wall consists of overlapping (secant) piles to form structural or cutoff walls and achieve the required water tightness. The design can incorporate steel bar or beams for reinforcement and anchors can provide additional lateral support, if needed.
What are secant piles made of?
They are typically made from steel or reinforced concrete, or sometimes timber. Pile walls can be used to create permanent or temporary retaining walls. They are formed by placing piles directly adjacent to one another.
When would you use a secant pile?
Secant Pile Walls are usually installed as retaining structures and support systems for deep foundations, retaining elements and at the same time load-bearing walls and deep foundations for engineering constructions (e.g. walls and foundations of underground storeys, stand-alone and framed bridgeheads, etc.).
Are secant piles waterproof?
Secant walls are designed to be water resistant. Secant pile walls are usually installed as retaining structures and support systems for deep foundations, retaining elements and at the same time load-bearing walls for engineering constructions.
How is secant pile installed?
The secant piles are reinforced with either steel rebar or with steel beams and are constructed by either drilling under mud or augering. Primary piles are installed first with secondary (male) piles constructed in between primary (female) piles once the latter gain sufficient strength.
What is cased secant piling?
Cased Secant Piling (CSP) piles are constructed by drilling hollow stem augers encased within a string of casing to the required depth. A twin rotary drive system rotating in opposite directions allows soil extraction and casing installation simultaneously.
Are secant pile walls permanent?
The perimeter secant wall served as both the permanent structural basement wall and the temporary earth-retention system for the new hospital building.
What are the advantages of contiguous piling?
Top 10 Advantages of Contiguous Pile Walls
- Easier to build in load variations, with no requirement for a guidewall.
- It’s a cost-effective bored pile solution, compared to Diaphragm walls.
- They can be used for more flexible geometry than a diaphragm wall.
- Load bearing capacity.
- Can be installed in difficult ground conditions.
How do you waterproof a secant pile?
These include: (1) a simple pressure wash of the surface of the secant piles; (2) a thin section topping over the entire surface of the secant piles to smooth out the surface but maintain the rolling profile; and (3) a final wall or a full depth concrete cover over the entire face thus leaving a flat surface as the …
Are secant piles temporary?
Cased Secant Piling The CSP system has been developed to combine the more cost-effective CFA technique with temporary casings that are more traditionally associated with rotary bored piling methods. The CSP system generally has the following advantages: Better tolerance than an un-cased CFA secant wall.
What is shear wall design?
In structural engineering, a shear wall is a vertical element of a seismic force resisting system that is designed to resist in-plane lateral forces, typically wind and seismic loads.
What is a secant wall?
Used extensively in dense population areas due to the minimal disturbance they cause to adjacent structures, secant walls are a form of top down construction used for environmental remediation and soil retention. The design of the head allows the piles to be right on the border or walls of the adjacent property, maximizing the usable area for development.
What is pile cap design?
Design of Pile Cap. A pile cap is the mat that rests on groups of piles and forms part of the foundation. The pile cap design, shape, and dimensions are discussed here.