1. Form a 'guidewall' with predetermined spacing to accurately position the secant pile prior to drilling operations.
2. Drill and cast a series of female (unreinforced) piles formed in soft or firm concrete.
3. Drill the corresponding series of male piles through the previously cast female piles utilising the casing or heavy duty augers to cut the required secant male pile to design depth.
male piles through the previously cast female piles with the required design intersect utilising the casing to cut the required secant
4. Cast the male piles with full reinforcement cage (and withdraw the casing, if used) to allow the concrete in the male piles to flow and bond with the existing concrete of the previously cast female piles.
5. Install a capping beam to tie piles together; ensuring the wall acts as a monolithic structure.
6. Excavate soil in from in front of the wall to allow the secant wall to retain the soil behind.
7. Install temporary and/or permanent propping where design requires.