微型桩单桩抗弯承载力计算公式的推导及验证

在微型桩加固边坡工程中,桩体的抗弯承载力是评价边坡稳定性的重要指标。因此,提出了微型桩等效刚度的计算方法,基于混凝土钢管桩抗弯承载力公式,并考虑受压区水泥砂浆体的影响,推导了两种不同配筋截面类型微型桩的抗弯承载力计算公式。最后,通过三点加载的数值试验获得了加载过程中微型桩的受力状态以及应力分布情况,并得到了微型桩受荷的荷载-挠度曲线,验证了微型桩抗弯承载力计算公式。结果表明,数值试验的结果与抗弯承载力计算公式计算的结果接近,且相对偏安全,满足工程要求。

Derivation and Verification of Calculation Formula forthe Bending Capacity of Single Micro-Piles

In the process of the micro-pile reinforced slope engineering, the flexural bearing capacity of piles is an important indicator for the evaluation of the stability of the slope. Therefore, the calculation method of equivalent stiffness of micro-piles has thus been proposed. Based on the formula of flexural capacity of concrete-filled steel tubular piles and taking into consideration such factors as the influence of cement mortar in the compression area, a derivation of calculation formula can be achieved of the flexural capacity of two micro-piles with different reinforced sections. Finally, the stress state and distribution of micro-piles in the process of loading can be obtained based on three-point numerical tests, thus obtaining the load deflection curves of micro-piles, which verifies the calculation formula of bending capacity of micro-piles. The results show that the numerical test results are close to the results calculated by the formula of flexural bearing capacity, which are relatively safe and meets the engineering requirements.