塑性混凝土防渗墙配合比设计及在水利工程中的应用研究

Research on the Mix Design of Plastic Concrete Anti-seepage Wall and its Application in Hydraulic Engineering

文中基于某水利枢纽塑性混凝土防渗墙施工需求,以水泥掺量、膨润土掺量及砂率为参数进行塑性混凝土配合比设计研究,分析各参数对塑性混凝土流动性能、力学性能及抗渗性能的影响。结果表明,相同水胶比情况下,增加水泥掺量能够改善塑性混凝土的力学性能和抗渗性能,当水泥掺量由80 kg/m3增加到200 kg/m^(3)时,塑性混凝土的抗压强度、弹性模量分别增大2.3、239 MPa,相对渗透系数减小0.411×10^(-7)cm/s;相同水泥掺量下,增加膨润土掺量能提高塑性混凝土的抗渗性能,但会导致塑性混凝土的流动性能和力学性能下降;适当增大砂率有助于降低相对渗透系数,提高塑性混凝土的抗渗性能;选用C160B80SR60作为该工程塑性混凝土防渗墙施工配合比,养护28 d后塑性混凝土的平均渗透系数为6.13×10^(-8)cm/s,满足设计及规范要求。

Based on the construction requirements of a certain water conservancy hub's plastic concrete anti-seepage wall,a study was conducted on the mix design of plastic concrete using cement content,bentonite content,and sand ratio as parameters.The influence of each parameter on the flow performance,mechanical properties,and anti-seepage performance of plastic concrete was analyzed.The results show that increasing the cement content can improve the mechanical and anti-seepage properties of plastic concrete under the same water cement ratio.When the cement content is increased from 80 kg/m^(3) to 200 kg/m^(3),the compressive strength and elastic modulus of plastic concrete increase by 2.3 MPa and 239 MPa,respectively,and the relative permeability coefficient decreases by 0.411×10^(-7) cm/s.Under the same cement content,increasing the content of bentonite can improve the impermeability of plastic concrete,but it will lead to a decrease in the flowability and mechanical properties of plastic concrete;Appropriately increasing the sand ratio can help reduce the relative permeability coefficient and improve the impermeability performance of plastic concrete.C160B80SR60 was selected as the construction mix ratio for the plastic concrete antiseepage wall in this project.After 28 days of curing,the average permeability coefficient of the plastic concrete was measured to be 6.13×10^(-8)cm/s,which meets the design and specification requirements.