07-22-2009, 04:17 AM
It is not economical to put the piles on a closer distance to act like a continuous support for your wall. Number of piles is decided on the actual axial load transferred from your wall load. In any case your wall will still be supported continuously as you need to have a continuous pile cap so that all loads will be transferred correctly to your piles and eventually to your soil foundation. Even if you are just using micropiles it still need a reasonable width of pile cap that is most likely still be more than the width of your wall making it a continuously supported wall with continuous footing (pile cap) that transfers the load to your piles.