泥石流拦挡坝的加高加固方案及对比研究

The Scheme and Contrast of Debris Flow Blocking Dam Heightening and Strengthening

结合宕昌县大地沟泥石流重力式实体坝的加固加高设计,提出了2种加高加固方案。以计算流体动力学为基础,通过CFX软件建立泥石流流体模型,得到泥石流流体的流场和拦挡坝的压力特征。利用有限元分析2种加高加固方式在泥石流整体冲击力和块石撞击力共同作用下的水平位移及结合面剪应力的情况,得到水平位移随时间的变化曲线。结果表明:对于加高加固后的坝体,块石撞击力对位移的影响并不大;采用扶壁式加高加固方式的坝体刚度较大,抗滑性和抗倾覆性基本相同,并且更加节约混凝土的用量;但结合面剪应力分布比较集中。

Combining the design of heightening and strengthening of the debris flow blocking dam in Dadi Trench of Tanchang County,two kinds of heightening reinforcement scheme is proposed. Based on fluid dynamics, the mud fluid and the pressure in blocking dam are determined in this paper by modeling mud fluid in CFX. To analyse the horizontal displacement of both heightening and strengthening schemes by using finite element analysis software, we obtain the horizontal displacement curve. The results show that, for the heightening and strengthening dam, the influ- ence of stone impact force on the horizontal displacement turns out to be small;Buttressed height- ening and strengthening scheme has more rigidity, but the sliding resistance and resistance to cap- sizing are basically the same, and it is helpful to save the amount of concrete; However, shear stress distribution is more concentrated in combination surface.