砂土中考虑冲刷的水平受荷桩等效应变楔方法

冲刷引起桩周土体的损失，研究冲刷效应对桩基水平承载特性的影响非常必要。基于桩前土体楔形受力的应变楔方法可以推导桩侧p-y曲线，进而分析水平受荷桩的受力变形特性，但只适于地表水平的情况。基于冲刷坑坑底以上土体的自重荷载对楔形体的开展范围进行深度等效，建立了冲刷条件下砂土中水平受荷桩的等效应变楔方法。通过与文献对比，验证了该方法的可行性。研究结果表明：冲刷深度增加，冲刷坑底宽度增大及冲刷坡角减小均会降低桩基水平承载性能。与仅考虑冲刷引起的桩侧极限抗力削弱的简化方法相比，本研究得到的桩基最大弯矩偏小。将冲刷坑底以上土层全部剥蚀的做法，忽略了冲刷深度内的土层作用，计算结果会偏于保守。

Equivalent-strain wedge method for laterally loaded pile in sand considering scouring effect

As scouring can induce soil loss around pile foundations, it is important to investigate the scouring effect on laterally loaded piles. The strain wedge method is an effective method to predict the p-y curve and to analyze the deformation characteristics of laterally-loaded piles, which can only be applied to the case of horizontal ground surface. An equivalent-strain wedge method considering scouring effect is proposed based on the equivalent depth of the strain wedge above the bottom of scour hole. The validity of the method is confirmed by comparing it with those in the literatures. It is found that the lateral responses of a pile decrease with the increase of scouring depth and scouring width at the bottom of a scour hole, and also with the decrease of scour slope angle. Compared to the simplified method, in which only the ultimate lateral pile resistance is affected by scouring, the present method yields a smaller maximum bending moment on pile. Removing the whole soil layers above the scour bottom would result in a conservative result due to omitting the effect of soil layers located in the range of scouring depth.