Calculation method of stabilizing piles with broadened top at the built-in section

In order to solve lacking of horizontal bearing capacity of local strata resistance before built-in section of the stabilizing pile, stabilizing piles with locally broadened top at the built-in section is proposed as a new type pile. According to analysis model of laterally loaded beam on elastic foundation, formulas for internal forces, displacement and strata resistance of the pile built in multiple stable layers are derived. Analysis results of an example show that if the width of the broadened section reaches double width of the normal pile, the resistance of the strata at the top of the broadened section reduces about 25% and the maximum bending moment and shear force of the pile decreases about 5%−10%. Further, influence of main factors such as broadened width and depth, length of the pile part in stable layers and pile spacing on internal forces and displacements of the pile is discussed. The results indicate that compared with the normal piles, the lateral displacement and the strata resistance of the new pile are significantly reduced. The horizontal bearing capacity of the broadened pile is increasing with the broadened width and depth as well as length of the built-in section. However, the improvement of the horizontal bearing capacity of the local strata is limited if the broadened pile width reaches double width of the normal pile and the broadened depth exceeds 40% of the length of the built in section.