宽级配砾石土坝料的防渗性及反滤

Permeability, Erosion Resistance and Filters of Broadly Graded Gravelly Soil for Embankment Dam Construction

摘要: 本文结合瀑布沟工程,系统地研究了宽级配砾石土的防渗性和渗透稳定性,提出了宽级配砾石土抗冲蚀破坏的极限反滤标准。研究表明,当细料含量P<0.1大于25％时,宽级配砾石土可以满足大坝防渗要求;且宜按湿于最优含水量2％～3％填筑。保证宽级配砾石土防渗体免遭渗流冲蚀破坏的极限反滤标准为:当P<0.l小于30％时,D₁₅≤1.1mm,D₁₅/d₃₅^△≤15～17;当P<0.1 大于30％时,D₁₅=1.1mm,D₁₅/d_/（（?）5）^△≤20。

Abstract: In connection with the construction of Pubugou Project, anti-seepage behavior and piping resistance of gravelly soil with broad gradation were studied systematically and the criteria of critical filter for resisting erosion failure of gravelly soil were proposed. Results showed that gravelly soil will fulfill impermeability requirement when P_<0.1 of fine particle content >25% and the effect of impermeability will be more remarkable when filled with 2%³% on the wet side of optimum water content; the criteria of critical filter for preventing core material from erosion failure are D15≤1.1mm, D₁5/d₈5⁴≤15¹7 when P_<0.1<30%,andD₁5≤1.1mm, D₁5/d₈5⁴≤20 when P₀.1>30%.