现浇X形混凝土桩与圆形桩承载性状对比试验研究

Comparative tests on bearing capacity of cast-in-situ X-shaped concrete piles and circular pile

通过现浇X形混凝土桩与等截面圆形桩、等周长圆形桩足尺模型静载试验,对比分析了试验各桩桩身轴力分布、桩侧摩阻力以及桩端阻力的发展情况,并对X形桩的荷载传递机理进行了深入研究。试验结果表明:对于本次研究对象的X形桩,与等截面圆形桩相比:其极限承载力及桩身单位体积混凝土极限承载力均为等截面圆形桩的1.32倍,与等周长圆形桩相比:其极限承载力及桩身单位体积混凝土极限承载力分别为等周长圆形桩的0.84倍与1.47倍。从提高桩基承载力,节约桩身混凝土用量角度来看,X形桩是一种具有较高的竖向承载力且造价低的新型桩,因此该桩在软土地基中有广泛的推广和应用价值。

Through the full scale static load model tests on the cast-in-situ X-shaped concrete piles and circular piles with the same cross-section area and circular piles with the same perimeter,the distribution of pile axial force and the development of pile shaft resistance and pile toe resistance are comparatively analyzed,and the load transfer mechanism of the X-shaped piles is studied.The test results show that： for the X-shaped piles,the ultimate bearing capacity and the bearing capacity per unit volume of pile concrete are both 1.32 times those of the circular pile in the same area,and 0.84 times and 1.47 times respectively those of the circular piles with the same perimeter.From the view of improving the bearing capacity of the pile and saving the amount of pile concrete,the X-shaped pile is a new pile with is high vertical bearing capacity and low cost,therefore it has the extremely high promotion and application value in soft soil foundation.