黄河三角洲埕北海域底质沉积物粒度特征及泥沙输运分析

摘要

Based on the analysis of 181 grain size testing data which sampled in Chengbei sea area,and combine with the tidal observation data and the elements of wave in 50 years,analyzing the types of surface sediment and the grain size pattern,calculating surface sediment shear stress,the average net transport flux and bed-load transport rate under the interaction of wave and current,the results show that the sediment is mainly composed of silty sand,sandy silt,silt and mud.The grain sizes are all poor sorted and the skewness are objective to symmetrical.In most places of Chengbei area the tidally-induced shear stress is larger than the critical shear stress,it shows that the tide can start and transport the sediment in most places.The average net transport flux per day is 372.32 kg/(m · d).Under the action of both tide currents and waves in 50 years,the daily sediment bed-load transport rate is approximately equal based on the theory of Bijker and Van Rijn.%通过黄河三角洲埕北海域表层沉积物的粒度资料、实测潮流数据以及50 a一遇的波浪要素,分析了埕北海域表层沉积物的分布类型以及粒度参数特征,并计算了表层沉积物的临界起动应力、日平均单宽输沙通量以及波流共同作用下的单宽推移质输沙率.结果表明:研究区表层沉积物主要是粉砂质砂、砂质粉砂、粉砂和泥四种,分选中等偏差,近对称到正偏,中等尖锐到尖锐峰态;对大潮期间埕北海域潮流底应力和表层沉积物的临界起动应力的计算说明潮流在大部分区域具有起动和输运泥沙的作用;秋季潮流作用下的日平均单宽输沙通量均值为372.32 kg/(m·d),方向为涨潮流向.利用贝克尔(Bijker)和经典的Van Rijn公式计算出的50 a一遇的波流共同作用下单宽推移质日平均净输沙率结果近似相等.