| In recent years,the batter pile has been widely used in pile group foundation such as bridges,offshore drilling platforms and wind power generation,and has attracted the attention of geotechnical engineers.Different from the vertical pile,the distribution of soil stress field around batter piles is asymmetrical to pile axis,which makes the bearing characteristics of the batter pile more complicated than that of the vertical pile.In actual engineering,the batter pile’s apex will support both the horizontal and vertical loads.For instance,the batter pile not only bears the self-weight load of the superstructure,but also suffers the horizontal load caused by the wind,which has changeable directions.Few studies have been done on the situation where the horizontal load is batter at an angle with the batter plane of the pile body,but most studies on the horizontal bearing characteristics of batter piles concentrate on the case where the direction of the horizontal force is coplanar with the batter plane of the pile body.Therefore,it is of great significance for engineering application to study the bearing characteristics of the batter pile under horizontal oblique load and vertical load.Based on the above background,this paper mainly carried out the following studies on the batter pile with a tilt Angle of 15°:(1)Laboratory model tests were first conducted,in order to evaluate the pile top displacement and bending angle of batter piles under horizontal oblique loads of 0°,90°,and 180°and vertical compression loads in sandy soil.The test findings demonstrate that the increase of horizontal load angle will reduce both the vertical displacement of the pile tip in the square direction and the horizontal displacement of a single pile tip.With the increase of vertical load,The horizontal displacement and vertical displacement of the pile top under 0°and 90°horizontal loads will increase.while under a 180°horizontal load,the pile top’s horizontal displacement and vertical displacement will both be minimized.(2)By using ABAQUS finite element software,we have studied the Pile top displacement,pile internal force,and lateral friction resistance of batter pile under horizontal oblique load of 0°,45°,90°,135°,and 180°as well as vertical compression stress.The numerical analysis results demonstrate that the increase of horizontal load angle will decrease both the vertical displacement of the pile tip in the square direction and the horizontal displacement of a single pile tip.Under 0°-90°horizontal load,the increase in vertical load will increase the horizontal displacement and the vertical displacement of the pile top;however,under 90°-180°horizontal load,the impact is opposite.Pile’s bending moment is mainly distributed in its half section,and with the increase of vertical compression load,the pile’s axial force and side friction will be also increased.When the horizontal load Angle is different,the vertical load has a different impact on the bending moment and shear force of the pile.The proposed empirical formula for the maximum bearing capacity of a 15°batter pile under the combined action of a horizontal load and a vertical compression load is based on model testing and numerical analysis.(3)We have numerically simulated the bearing characteristics of a group of 1×2battered piles under a horizontal oblique force and a vertical downward load to study the influence of vertical downward load on the displacement,internal force and lateral friction resistance of 1×2 batter pile group.According to the findings,the increase of horizontal load angle and the vertical downward load will increase the horizontal displacement at the cap and decrease the ultimate horizontal bearing capacity of the batter pile group,but the impact on vertical displacement is opposite.In addition,the presence of vertical downward load will increase the negative frictional resistance,the axial force,the bending moment M_y in the y-direction,and the shear force F_x in the x-direction of the pile body. |
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