无砂大孔生态混凝土关键指标评述

Review of key indicators for large-porous ecological non-fines concrete

为了研究无砂大孔生态混凝土植生性的影响因素,配制既能提供草木植被生长所需条件,又能满足施工作业要求的混凝土。通过对比普通混凝土与土壤内部结构、成分含量,提出了无砂大孔生态混凝土的植生性控制指标：连通孔隙率大于25%、沉浆面积率小于5%、抗压强度为5~15 MPa。进行了粗骨料级配试验及改变水灰比优化试验,研究结果表明,合理选择水灰比及骨料级配后,无砂大孔生态混凝土的连通孔隙率可以达到25%,沉浆面积率可以控制在5%以下,抗压强度达到9 MPa。使混凝土的绿化与硬化要求有机结合起来。

In order to study the factors that affect the characteristics of plant-growing of large-porous ecological non-fines concrete,we prepare a type of concrete that is not only beneficial to plant growing but also meet the strength requirement.We put forward the controlling indicators of plant-growing of ecological concrete by comparing the internal structure and composition of normal concrete and soil： pore connectivity larger than 25%,deposition paste area ratio less than 5%,and compressive strength of 5~15 MPa.We conducted tests of aggregate gradation and water cement ratio optimization;and it is shown that by optimizing the aggregate gradation and water cement ratio,the pore connectivity of large-porous ecological non-fines concrete could reach 25%,deposition paste area ratio could be controlled under 5%,and the compressive strength could reach 9 MPa.The new type of ecological concrete is an organic integration of greening and ground hardening.