Group effects of piles due to lateral soil movement

Laboratory model tests have been conducted to investigate the responses of piles subjected to lateral soil movement. The results of a single pile test and four tests on two piles arranged in a row perpendicular to the direction of soil movement are presented. The development of maximum bending moment, maximum shear force, and pile deflection with soil movement and the largest pile response profiles for the single pile and pile groups are compared. Group effect was evaluated using group factor which is defined in terms of the measured maximum bending moment. The major findings are (1) the pile head conditions (free or capped) are insignificant on piles subjected to lateral soil movement when arranged in a row, (2) the group factor decreases as the pile spacing reduces, (3) a linear relationship exists between the maximum bending moment and maximum shear force for both the pile groups and single pile.