Effect of pile cap elevation below ground surface on lateral resistance of pile groups-experimental study

Abstract

This paper presents the results of experimental study on model piles to show the effect of pile cap elevation below the ground surface and pile spacing on lateral resistance of single pile and pile groups driven in sand. Thirty five tests were performed on single piles and 2 x 2, 3 x 3, 4 x 4 pile groups at pile spacing equal to 3<i>D</i> and 5<i>D</i> with pile cap located at different elevation below the ground surface. Five cases for pile cap elevation were considered: case 1, bottom of pile cap in contact with the ground surface; case 2, top of pile cap at the ground surface elevation; case 3, bottom of pile cap below the ground surface at a depth where <i>D_f/t</i> equal 2; case 4, bottom of pile cap below the ground surface at a depth where <i>D_f/t</i> equal 3.33; and case 5, bottom of pile cap below the ground surface at a depth where <i>D_f/t</i> equal 6.67. In all the studied cases, the pile tips located at the same elevation. The results of the tests show that the lateral carrying capacity of single pile and pile groups increase as the pile cap depth below the ground surface, <i>D_f</i>, increases and as the spacing between piles in the group increases.