基坑支护倾斜悬臂桩受力变形特性试验研究

为改善基坑工程中支护桩的受力特性,将传统的直立悬臂桩背向基坑倾斜一定角度,形成基坑支护倾斜悬臂桩,可以更好地承担水平荷载,减小水平位移和变形。通过模型试验的方法对基坑开挖过程中倾斜悬臂桩的桩顶水平位移、桩后土体沉降和桩身弯矩进行研究。试验共进行3种不同工况下的模拟,分析倾斜悬臂桩在不同倾角不同布桩方式下的受力特性。分析结果显示,同等条件下,倾斜悬臂桩较传统直立桩相比,可以有效减小桩底水平位移和桩后土体沉降;桩身弯矩会因基坑开挖深度的增大而增加,桩身的正弯矩峰值接近负弯矩峰值,斜桩的最大弯矩值显著小于直桩支护形式下的弯矩峰值。

Experimental Study on Stress and Deformation Characteristics of Cantilever Inclined Retaining Pile for Foundation Pit Support

To improve the bearing behavior of the retaining pile in foundation pit, the inclined cantilever pile, which is changed from the traditional cantilever pile to a certain angle to the foundation pit, can better bear the horizontal load and reduce the horizontal displacement and deformation. The horizontal displacement of the top of the cantilever pile, the settlement of the soil behind the pile and the bending moment of the pile body are studied through model tests. The tests were carried out under 3 different working conditions, and the stress characteristics of inclined cantilever piles under different dip angles and different pile arrangement modes were analyzed. The results show that under the same conditions, the inclined cantilever pile can more effectively reduce the horizontal displacement of the pile bottom and the soil settlement behind the pile than the vertical pile can. As the depth of the excavation increases, the bending moment of the pile body increases, furthermore the peak value of the positive and negative moments of the pile are similar, and the maximum bending moment of the inclined pile is significantly lower than that of the vertical pile.