为了准确评估堆场存储能力和合理选择疏浚泥处理工艺,以泥沙运动学为理论基础,将疏浚泥颗粒分为d〈0.005 mm、0.005 mm≤d≤0.01 mm和d〉0.01 mm 3个粒组,分析了各粒组相对含量的沿程变化规律,明确了堆场疏浚泥分选的主要原因是d〉0.01 mm粒组与0.005 mm≤d≤0.01 mm粒组的相对运动;以分选系数量化堆场疏浚泥分选的显著程度,以偏离系数量化原泥颗粒组成对堆场疏浚泥分选的影响,分析了分选系数、偏离系数分布与堆场疏浚泥土性分布的关系,提出了堆场疏浚泥分选特性的初步量化方法。研究结果表明:随着离吹填口距离的增大,分选系数沿程减小,呈幂函数分布,堆场疏浚泥分选性沿程减弱,吹填口附近分选系数最大,颗粒分选显著,粒度差异大,退水口附近分选系数趋近于零,分选不明显,颗粒分布均匀;偏离系数沿程先减小后增大,呈勺形分布,反映堆场前、后段疏浚泥土性与原泥相差较大,而堆场中段疏浚泥土性与原泥接近;分选系数、偏离系数的沿程分布与堆场疏浚泥土性分区具有良好的相关性。
In order to accurately evaluate the storage capacity of reclaimed land and reasonably select treatment technologies for dredged slurries,based on the theory of sediment transportation mechanics,dredged slurries are divided into three particle-size fractions: d〈 0. 005 mm,0. 005 mm ≤ d ≤ 0. 01 mm,and d 〉0. 01 mm. The variation of relative content for each particle-size fraction was analyzed,and it was determined that the main reason for grain sorting of dredged slurries is the relative movement of particle-size fractions d 〉0. 01 mm and 0. 005 mm≤d≤0. 01 mm. Using the sorting coefficient to quantify the significant degree of grain sorting of dredged slurries and the deviation coefficient to quantify the influence of grain composition of in situ mud on grain sorting,the relationships between the sorting coefficient and deviation coefficient and soil properties in reclaimed land were analyzed,and a preliminary quantitative method for grain sorting of dredged slurries in reclaimed land is proposed. The results show that the sorting coefficient decreases with the increase of the distance from the filling inlet and shows a power function distribution,and the significance of grain sorting decreases longitudinally. The sorting coefficient is at its maximum near the filling inlet,where grain sorting is remarkable and the particle-size difference is large. However,it is small near the water outlet,where grain sorting is unremarkable and particle-size distribution is uniform. The deviation coefficient decreases first and then increases longitudinally in reclaimed land,and shows a spoon-type distribution,showing that the soil properties in the forepart and posterior segment of reclaimed land are significantly different from those of in situ mud,but the soil properties in the middle segment of reclaimed land are similar to those of in situ mud. The longitudinal distributions of the sorting coefficient and deviation coefficient are strongly correlated with zoning of soil properties in reclaimed land.