NUMERICAL ANALYSIS OF WORKING CHARACTERISTICS OF DOUBLE ROW PILES

The mechanical response of double row pile under step excavation is studied through numerical simulation and using general international geotechnical analytic software FLAC; and the working character istics of the double row pile retaining system are discussed according to the distance between two rows and the insertion depth of a pile.The study shows that the space effect of a portal frame will be poor if the distance between two rows, s4d (d is the diameter of the pile).When s 8d the space effect of the portal frame is also poor with a tie beam acting as a tie bar. The rational range of the distance between two rows is 4d～8d. The displacement of a pile is decreased and its internal force is increased with increasing the insertion depth of the pile.