在大厚度人工填土地基上开展水平受荷单桩的现场试验,实测得到地面荷载-位移关系、转角和弯矩,揭示了水平荷载作用下桩-土相互作用规律。并探究了地基土水平抗力系数的比例系数m随荷载与位移的变化规律。结果表明:桩基水平临界荷载值为480kN,且达到临界后,桩基的水平位移和转角均发生了突变；桩基的弯矩图呈现“两头小,中间大”的分布模式,弯矩沿深度影响范围约为10m,水平抗力系数的比例系数随荷载和位移的增大呈幂级数减小。通过试验数据对m法计算结果进行验证与改进,对比发现m法计算最大位移与实测结果接近；计算弯矩当荷载超过临界荷载相差较大,通过修正系数函对弯矩计算结果进行修正,修正后的弯矩与实测值更加吻合。

The field test of single pile under horizontal load is carried out on the artificial fill foundation with large thickness. The load-displacement relationship, rotation angle and bending moment of the ground are measured, and the law of pile-soil interaction under horizontal load is revealed. The variation law of the proportional coefficient m of the horizontal resistance coefficient of foundation soil with load and displacement is also explored. The results show that the horizontal critical load of pile foundation is 480 kN, and after reaching the critical value, the horizontal displacement and rotation angle of pile foundation change suddenly. The bending moment diagram of the pile foundation shows a distribution pattern of " small at both ends and large in the middle ". The influence range of the bending moment along the depth is about 10 m, and the proportional coefficient of the horizontal resistance coefficient decreases exponentially with the increase of load and displacement. The results of m method are verified and improved by experimental data. It is found that the maximum displacement calculated by m method is close to the measured results. The calculation of bending moment when the load exceeds the critical load is quite different, compared to the correction coefficient function β, the m method is improved.……

国家自然科学基金资助项目(51868038)；甘肃省基础研究创新群体项目(21JR7RA347)