柴河水库淤积泥沙物理特性分析

Physical Characteristics Analysis of Sediment in Chaihe Reservoir

泥沙淤积是制约水库长期利用的关键问题之一,柴河水库自运行以来淤积物逐年增加,对此,采用声波钻机对库区典型断面展开现场取样,对取出的淤积泥沙样品开展土工试验。结果表明,库区表层淤积物干重度、粗沙含量沿程递减;泥沙干重度与粗颗粒泥沙含量随淤积厚度的增加而增大;库区淤积物干重度随泥沙粒径增大而增大;粒径为0.075~0.250mm之间的单颗粒泥沙沉速范围为6.281~30.026mm/s。计算单颗粒泥沙沉速时,泥沙粒径>0.200mm时宜采用张瑞瑾公式,粒径接近0.100mm时宜采用艾益龄公式。研究成果可为水库淤积分析计算、泥沙运动数值模拟及物理模拟研究提供参考。

Sediment deposition is one oi the key problems that restrict the long-term use of reservoirs. Since the oper- ation of Chaihe Reservoir, sediment has increased year by year. In this paper, sonic drilling rig was used for field sam- piing of typical section in the reservoir area, and the sediment samples were taken for geotechnical test and analysis. The results show that the dry bulk density and coarse sand content of sediment in the surface decreased along the way. Sedi- ment dry bulk density and coarse sand content increased with deposition thickness. Sediment dry density increases with the increasing of particle size in the reservoir region. The settling velocity of single particle size between 0. 075~0.25 mm ranges from 6. 281 to 30. 026 mm/s. To calculate single particle settling velocity, it is advisable to adopt the formula of Zhang Ruijin when the sediment grain size is greater than 0. 200 ram, while the AI Yiling formula is suitable for the parti- cle size close to 0. 100 mm. The research results can provide reference for calculation of reservoir sedimentation, numeri- cal simulation of sediment motion and research of physical simulation.