变截面桩承载特性及施工关键技术探讨

Discussion on the Bearing Characteristics and Key Construction Techniques of Variable Section Pile

变截面桩是在等截面桩的基础上改进而来的新桩型,但其受力变形相对复杂、施工影响因素较多。为进一步促进变截面桩在实际工程中的应用,对变截面桩承载特性和施工关键因素进行分析发现:变截面段是变截面桩承受横向和竖向荷载的主要部分,且存在最佳长度比例,超过此比例后,承载能力提升不明显;护筒直径、埋深,钻孔设备及方法,护壁泥浆等是影响变截面桩成桩的关键因素。

The variable section pile is a novel pile type improved on the equal section pile,which is gradually popularized and applied in practical projects.But the The mechanical behavior and deformation characteristics of variable section pile is complicated,and there are also many affecting factors in construction.By analysing the bearing characteristics of the variable section pile,it is found that the variable section is the main part to bear the transverse and vertical loads.And there is an optimal proportion for variable section length,beyond which the carrying capacity of variable section pile is not significantly improved.These factors of protective cylinder,buried depth,drilling equipment and method,protective mud play important roles in affecting the formation of variable section pile.