การวิเคราะห์เสาเข็มเอียงชนิดกลุ่มแบบใหม่ด้วยแนวคิดแรง ผสมผสานบนพื้นฐานการทดสอบแบบจำลองกายภาพ

Abstract

This study proposes the influence of inclined angles on single pile and pile group on vertical and horizontal load capacity based on testing of the physical model laboratory, which using stainless steel with smooth and closed ends. These pile models were installed in case of the single pile test with inclines of -30, -20, -10, 0, 10, 20 and 30 degrees from the vertical. For the pile group test with 0, 10, 20 and 30 degrees from the vertical that is similar. The physical models were formed by the dry and uniform sand was prepared with 70% relative densities (Dr). The pile embedding in 250 mm-deeper of sand and the horizontal force position is 150 mm-upper of sand. For the results of single pile that the maximum vertical load was found by pile with 10 degrees and then incline angle increasing that tends to decrease the vertical load and lower than in case of vertical single pile. When the pile angle was 30 degrees from the vertical that was found the increasing positive inclined pile resulting in the continuously decreased horizontal load. In the other hand, the increasing negative inclined pile was resulting in the slightly increased horizontal load until the maximum horizontal load by the negative inclined pile at -20 degree. After increasing negative inclined to -30 degree from the vertical affected to decreased horizontal load. For the results of pile group that the pile angle in first rage between of 0 and 20 degrees tends to increase the vertical load capacity. After that, increasing the pile angle tends to decrease the vertical load. However, the increasing of pile angle raise the maximum vertical load at every inclined angle of the pile. In terms of horizontal load capacity that was found the increasing inclined angle of pile tends to increase the horizontal load capacity. After that, increasing the pile angle tends to decrease. For group efficiency ( gE ), the pile angle increasing that tends to increased steadily the gE , both in the case of vertical and horizontal load. In the case of pile capacity vertical load, The vertical piles had the lowest gE was 56.9%, and when the pile angle was increased to 30 degrees from the vertical, gE was 138.7%, which increased by 81.8%. In the case of horizontal load piles Starting at vertical piles, the gE was 125.0% and when the pile angle increasing that tends to decreased the gE lower than the vertical pile during the pile angle.