Secant concrete shoring using helical piles for depth

A method of constructing a pile shoring wall, comprising:

• forming a plurality of tangent concrete piles in the ground and along an edge of an area that is to be excavated to an excavation depth, comprising:
• forming a plurality of first concrete piles in the ground at depths wherein the average depth is d1;
• and
• forming a plurality of second concrete piles which includes 10% and less than 50% of the tangent concrete piles, wherein forming each second concrete pile comprises:
• forming a bore hole in the ground, the bore hole having a bottom at a depth below ground surface level that is deeper than the excavation depth;
• installing a helical pile into ground material below the bottom of the bore hole, such that a shaft of the helical pile protrudes upwardly from the ground material and into the bore hole;
• and
• at least partially filling the bore hole with concrete such that the concrete fills around the protruding shaft of the helical pile and forms a column of concrete defining one of the second concrete piles.