在系列室内水槽试验中,运用黄河天然沙,中值粒径0.072 mm,通过11组水流挟带泥沙自然淤积的方式分3种固结历时研究了淤积固结过程中干容重的变化,并用清水进行冲刷,重点探讨了干容重取值对冲淤量的影响.结果表明:淤积物干容重随淤积历时的延长而增加,并且越靠近出口,淤积物中值粒径越细,干容重稳定所需要的固结时间越久;计算冲淤量时选取实测值越多精度越高;而经验取值误差较大,甚至有可能出现定性错误;对于相同的淤积体积,淤积历时越长,淤积量越大;在淤积体积相同的条件下冲刷相同的体积,淤积历时短的冲刷量大.
The dry bulk density change is studied basing on 11 groups of experiments of sediment-carrying flow with 3 different kinds of consolidation durations in generalized experimental flume series,which used the natural cohesive sediment that median size is 0.072 mm,scoured with clear water,and influence of dry bulk density valuing on scour and silting amount is discussed.Research result shows that the longer the consolidation duration is,the bigger dry bulk density will be made.And the closer to the outlet of flume,median size is more fine,the more time stable dry bulk density will be needed.When calculating scour and silting amount,the more measured values is,the higher accuracy will be made,the experience values can bring bigger error,sometime there may even be qualitative error.For the same volume,longer consolidation duration brings bigger silting amount;if scour the same volume under the same silting amount,short duration of consolidation always brings larger erosion amount.