An Analytical Transformation Algorithm for Loading-Settlement Curves of Rock-Socketed Piles in Soft Rock by Self-Balanced Tests
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摘要: 为更准确反映软岩地基中自平衡试桩结果,提出一种针对软岩嵌岩桩承载力的自平衡试桩结果解析转换算法。首先,通过分析桩–软岩接触面剪切机理,建立了考虑胶结、剪胀以及滑移三个剪切阶段的桩–软岩接触面荷载传递函数和模型。其次,考虑荷载箱上段桩重力的影响并结合桩–软岩接触面荷载传递函数,推导出自平衡试桩荷载–沉降曲线的理论解析解,通过将两根试桩的实测数据与理论解析解结果进行对比,计算得出理论解析解的精确度分别为87.3%和85.6%。最后,在现有简化转换法基础上提出解析转换法,通过与精确转换法结果进行比较,解析转换法结果较简化转换法结果精确度分别提高了15.3%和17.4%。解析转换法简单实用且精确度较高,可为软岩嵌岩桩自平衡试桩工程提供一定的参考。Abstract: To more accurately reflect the test results of the bearing capacity of piles by self-balanced tests in soft rock foundation, an analytical transformation algorithm for the tested bearing capacity of rock-socketed piles by selfbalanced tests was proposed. Firstly, the shear mechanism of interfaces between piles and soft rock was analyzed, and a transfer function of loads and model for the interfaces between piles and soft rock were established considering the three shear stages of cementation, shear dilation and slip. Secondly, the analytical solution for loading-settlement curves of piles by the self-balanced tests was deduced considering the influence of the pile weight of the upper section on the loading box and combining the load transfer function of the interface between piles and rock. Comparing the measured data of two test piles with the calculating results by the analytical solution, the accuracy calculating results by the analytical solutions was 87.3% and 85.6% respectively. Eventually, based on the existing simplified transformation method, an analytical transformation method was proposed. Comparing the results with the precise transformation solutions, the accuracy of the calculating results by the analytical transformation solution was respectively improved by 15.3% and 17.4% compared with the calculating results by the simplified transformation method. The analytical transformation method was simple, practical, and more accurate, which could provide reference to self-balancing tests in engineering with rock-socketed piles in soft rock.
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