沉沙池内拦沙帘拦沙特性试验研究

Experimental study on sand blocking characteristics of silt curtain in the settling basin

本文针对沉沙池内拦沙帘拦沙特性,以原型拦沙帘为研究对象,通过二维水槽物理模型试验研究了拦沙帘的渗透系数和不同潮位时的截沙率,分析了不同因素(流速、潮位、泥沙粒径)对拦沙帘截沙率的影响。研究结果表明,拦沙帘的渗透系数不仅与自身孔隙值大小、形状和连通性有关,也取决于所在含沙水体的运动变化情况,当水流流速越快时,拦沙帘横向渗透系数越小;拦沙帘对粒径较大泥沙的截沙率更高,且其他条件不变时,水流流速越快,拦沙帘下方逸沙空隙越大即潮位越高时,截沙率明显降低。

This article contraposes the sand blocking characteristics of silt curtain,two-dimension physical model experiments were conducted to study the horizontal permeability coefficient and sand blocking effectiveness.The effects of different elements(current speed,tide level and sediment grain size)were considered respectively to analysis the influence of sand blocking effectiveness.The results of this research shows that,the horizontal permeability coefficient of silt curtain is not only related to the size,shape and connectivity of pore,but also depends on the sandiness water movement where it is in.The horizontal permeability coefficient reduces with the current speed increase.The silt curtain shows a higher sand blocking characteristics for a larger sediment grain size.The faster current speed and the bigger sand-carrying gap that is it means the higher tide level leads to more obvious sand blockingeffectiveness decrease with other conditions unchanged.