基于膨润土净水型透水再生混凝土的配制试验研究

Experimental Study on Preparation of Water Purifying Pervious Recycled Concrete Based on Bentonite

文章通过500℃高温改性膨润土等比例替代水泥、再生骨料取代粗骨料、掺加粉煤灰配制透水混凝土,根据膨润土的掺加比例和不同粒径制订了六组试验方案,研究了每个方案透水再生混凝土的力学性能、孔隙率和透水系数的变化规律,并对混凝土性能变化进行了机理分析。研究表明:膨润土最佳掺加比例是20%,该配比透水再生混凝土抗压强度达到17.05 MPa,透水系数为1.73 mm/s,基本达到城镇硬化地面净水型透水混凝土的标准,为海绵城市硬化地面铺装寻求了依据。

Pervious concrete is prepared by replacing cement with bentonite modified at 500℃in equal proportion,replacing coarse aggregate with recycled aggregate,and adding pulverized-coal ash.According to the mixing proportion and particle size of bentonite,six groups of experimental schemes are designed.The mechanical property,porosity and pervious coefficient of the pervious recycled concrete for each group are measured,and the variation mechanism of these properties of concrete is analyzed.The results show that the best mixing ratio of bentonite is 20%.In this case,the compressive strength of the pervious recycled concrete reaches 17.05MPa,and the pervious coefficient is 1.73 mm/s,which meets the basic requirements of water-purifying pervious concrete for urban pavement,and provides reference for the construction of pavement for sponge city.