Secant bored wall piles consist of overlapping primary (often referred to female) piles and secondary (male) piles. The primary piles are usually, though not always, un-reinforced.
Sheet piles is use to protect or retain the soil at the adjacent sides during excavation. The full wall is formed by connecting or interlocking the adjacent sheet pile section.
Contiguous bored wall piles consist of line of individual piles positioned at close centres and are formed by conventional continuous flight auger or rotary auger bored pile techniques.
Soldier steel beam and lagging walls are the most commonly used type of wall system in civil engineering work. This wall system uses discrete vertical wall elements spanned by lagging which is either timber or in more cases reinforced concrete panel.