论文部分内容阅读
通过截面几何特性分析和足尺模型试验,从理论分析和模型试验等多角度研究了现浇X形混凝土桩的力学特性。分析了X形桩截面3个参数对其截面力学效应的影响,并与等面积和等周长的素混凝土方形桩、圆形桩作了对比。结合试验结果,并针对X形桩有别于传统桩型的过度充盈反而削减承载力的特点,提出X形桩极限承载力计算公式。理论分析结果表明:从增大侧表面积、减少桩身混凝土用量的角度分析,X形桩优于方形桩,方形桩优于圆形桩。足尺模型试验结果表明:在相同的荷载条件下,与等面积圆形桩相比,X形桩沉降量小、侧摩阻力高;实测极限状态时X形桩承载力比等面积圆形桩提高了32%。
The mechanical characteristics of cast-in-situ X-shaped concrete piles are studied from the perspectives of theoretical analysis and model tests through the analysis of the geometric characteristics of cross-section and the full-scale model test. The effect of the three parameters on the mechanical behavior of the cross section of the X-shaped pile section is analyzed and compared with the square and circular piles of equal area and constant perimeter. According to the experimental results, the formula for calculating the ultimate bearing capacity of X-shaped piles is proposed according to the characteristics of X-shaped piles rather than the over-filling of conventional piles. The theoretical analysis shows that the X-shaped piles are better than the square piles, and the square piles are better than the circular piles in terms of increasing the lateral surface area and reducing the amount of concrete used in the piles. Full-scale model test results show that the X-shaped pile has smaller settlement and higher lateral friction than the equivalent circular pile under the same load. In the ultimate limit state, the X-shaped pile has a lower bearing capacity than the equivalent area circular pile Increased by 32%.