三维网垫喷播植草护坡防径流冲刷机理研究  

Research on mechanism of runoff-erosion prevention by 3-D mat planting grass for slope protection

作　　者：肖成志[1] 刘晓朋[1] 孙建诚[1] 

机构地区：[1]河北工业大学土木工程学院,天津300132

出　　处：《人民长江》2009年第19期93-96,共4页Yangtze River

基　　金：国家自然基金项目(50678032);河北省教育厅项目(2007431)

摘　　要：三维网垫喷播植草护坡作为一种重要生态防护形式而被广泛用于土木工程领域。通过结合水力学和河流动力学原理,分别采用坡面糙率和拦淤栅模型来模拟三维网垫和坡面植被作用,建立了网垫引起的坡面沿程水头损失和植被引起的径流局部水头损失计算式,并由此建立了三维网垫喷播植草护坡时坡面径流速度的计算表达式,综合对比分析了边坡坡角、网垫类型、植草类型和植株密度对坡脚流速的影响。结果表明:坡脚流速随坡角增大而增大;坡脚流速随网垫类型变化而无明显变化,但无护坡时流速明显降低;坡脚流速随植株和叶部倾角增加及植被密度增大而减小。通过计算还得到不同土质边坡的颗粒启动速度与坡脚速度相等时,护坡所需植株最小密度值。所得结果对三维网垫喷播植草护坡的工程实践具有重要的指导意义。As an important ecological slope protection method,the 3-D mat planting grass for slope protection has been applied broadly in civil engineering.In this paper,applying theories of hydraulics and river dynamics,the authors simulate the function of 3-D mat and slope vegetation with slope roughness and trash rack models,and develop the formula of the frictional head loss caused by mat and the local head loss of runoff caused by vegetation.Based on this formula,the runoff velocity calculation expression for slope surface covered by 3-D planting grass mat is established.They also comparatively analyze influences on flow velocity at slope toe,which are caused by slope angle,mat type,grass type and plant density.The results are as follows: flow velocity at slope toe increases while slope angle increases;it has no obvious change while mat type varies,but decreases obviously without slope protection;and the velocity reduces with increasing of obliquity of leaves and vegetation density.The calculations show that,if particle start velocity of slope equals that of slope toe,the slope protection just needs minimum plant density,even though different qualities of earth slope.All these results can give an instructional reference to those 3-D mat planting grass for slope protection works.

关 键 词：水头损失 径流 生态护坡 坡脚流速 三维土工网垫喷播植草 

分 类 号：X171[环境科学与工程—环境科学]