锚索预加力对基坑变形及结构内力的影响研究

以北京市通州区的某一深基坑为依托,运用启明星计算软件。对不同锚索预加力下深基坑桩锚支护体系的基坑变形和结构内力进行分析,确定锚索预加力施加值的合理区间。分析表明:随着锚索预加力增大,基坑水平变形大幅度减小,幅度基本稳定,支护结构内力减小,减小幅度呈递减趋势;与锚索预加力增大至0.5N_k相比较,锚索预加力增大至0.8N_k时对基坑变形、支护结构内力影响作用有下降趋势,建议锚索预加力为0.5～0.8倍的轴力标准值。

Study on the Influence of Anchor Cable Preloading on Foundation Pit Deformation and Structural Internal Force

Based on a deep foundation pit in Tongzhou district, Beijing, Qimingxing calculation software was used. The deformation of foundation pit and structural internal force of deep foundation pit pile-anchored support system under different anchor cable preloading were analyzed and the reasonable interval of the applied value of anchor cable preloading was determined. The analysis shows that with the increase of anchor cable preloading, the horizontal deformation of foundation pit decreases greatly and the amplitude is basically stable. The internal force of the support structure is decreasing. Compared with the increase of anchor cable preloading to 0.5N_k, the effect of anchor cable preloading to 0.8N_k on the internal force of foundation pit deformation and support structure has a decreasing trend. It is suggested that the anchor cable preloading should be 0.5~0.8 times of the standard value of axial force.