摘要
为获得水平受荷斜桩的p-y曲线,在中密干砂中开展4根斜桩及1根直桩的模型试验,对试验结果拟合得到模型桩桩侧土反力及桩身横向位移之间的p-y曲线。通过三轴试验得到砂土的(35)?-?曲线。将模型桩的p-y曲线及砂土的(35)?-?曲线无量纲化并建立二者之间的关系,在此基础上建立砂土中水平受荷斜桩的p-y曲线,并给出相关参数的确定方法。分析表明,基于p-y曲线的计算结果与模型试验及文献中的离心模型试验结果吻合较好,这说明所建立的p-y曲线是合理的,能反应斜桩与桩侧土之间复杂的挤压、剪切相互作用。最后,应用p-y曲线对影响水平受荷斜桩性状的因素进行分析。结果表明,与桩顶自由时相比,斜桩桩顶固支可以有效减小桩身位移和桩身最大弯矩。斜桩桩顶竖向荷载的存在减小了负斜桩的横向位移和最大弯矩,而增大了正斜桩和直桩的横向位移和最大弯矩。桩身刚度较小时,增大桩身刚度可以有效减小斜桩桩顶横向位移和桩身最大弯矩。
In order to obtain the p-y curves of laterally loaded piles in sand,a series of model tests including four battered piles and one plumbed pile embedded in the medium-dense dry sand were conducted and the relationship between the soil resistance p,and the lateral displacement y,of pile shaft was obtained by fitting the model test results. In addition,the stress-strain（（35）？-？） curves for the sand used in the model tests were obtained based on the tri-axial compression test. A new p-y curve for laterally loaded batter piles was proposed according to the relationship between the dimensionless p-y expression and the dimensionless（35）？-？ curves. The methods to determine the parameters in the p-y curve were also given. The comparisons between the calculated results based on the p-y curve proposed,the model test results and the centrifuge model tests from references demonstrated that the p-y curve proposed for the laterally loaded batter piles was reasonable and can be used to describe the complex compression and shear behavior between the inclined piles and the surrounding soils. Finally,The p-y curves were used to analyze the behaviors of the inclined piles under different conditions and it was found that the lateral displacements and the maximum bending moments induced in the batter piles with the head fixed are less than that of batter piles with the head free. The existence of the vertical load on the pile head can reduce the lateral displacement and the bending moment in the negative batter piles but increase that in the positive batter piles. The increment of the stiffness of inclined piles can effectively reduce the lateral displacements and the maximum bending moment of the piles.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2018年第3期743-753,共11页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51078308
51508455)
陕西省自然科学基础研究计划项目(2015JM5260)~~
关键词
土力学
斜桩
P-Y曲线
模型试验
soil mechanics
batter piles
p-y curves
model test
