管涌型尾粉砂临界水力梯度计算方法探讨

发布时间：2018-12-15 10:37

【摘要】：尾粉砂的结构构造特点决定了其临界水力梯度大于常规的砂性土,按常规计算公式得到的管涌型尾粉砂的临界水力梯度计算值远小于实测值,因此,常规土的临界水力梯度计算方法并不适用于尾粉砂。通过收集整理尾粉砂的物理与颗粒特征指标,对比分析流土型与管涌型尾粉砂的颗粒级配特征,得到尾粉砂产生管涌的颗粒级配条件。在分析尾粉砂颗粒形态特征、颗粒级配特征、孔隙特征与临界水力梯度之间的关系的基础上,用特定的尾粉砂试样测定发生管涌时的临界水力梯度与孔隙率(比)之间的函数关系,进而导出尾粉砂发生管涌的临界水力梯度的计算通式,最后通过室内试验检验按计算通式计算结果的可靠性。相关试验检验表明,该计算通式的计算结果与室内实测结果基本吻合,可用来估算尾粉砂发生管涌的临界水力梯度,估算值略偏于安全。
[Abstract]:The structural characteristics of tail-silt determine that its critical hydraulic gradient is larger than that of conventional sandy soil, and the calculated value of critical hydraulic gradient of tube-shaped tail-silt is far less than the measured value according to the conventional calculation formula. The calculation method of critical hydraulic gradient for conventional soil is not suitable for silt. By collecting the physical and particle characteristics of tail-silt, the particle gradation characteristics of fluid-soil type and tube-type tail-silt are compared and analyzed, and the particle gradation conditions of tail-silt are obtained. Based on the analysis of the relationship between the particle morphology, particle gradation, pore characteristics and critical hydraulic gradient, The functional relationship between critical hydraulic gradient and porosity (ratio) was determined by a specific sample of tail-silt, and the general formula for calculating critical hydraulic gradient of tubing of tail-silt was derived. Finally, the reliability of the general formula is verified by laboratory test. The experimental results show that the calculation results are in good agreement with the measured results, and can be used to estimate the critical hydraulic gradient of tail-silt piping, and the estimated value is slightly more safe.
【作者单位】：中国冶金科工集团公司武汉勘察研究院有限公司;
【分类号】：TV223.4

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