再生黏土砖骨料含量对透水混凝土性能的影响

Influence of recycled clay brick aggregate content on the properties of pervious concrete

为了探讨再生黏土砖骨料在透水混凝土中的应用问题,按总骨料中再生黏土砖骨料体积百分比不同配制了6组再生骨料,先对6组再生骨料的基本性能进行测试,再对6组再生骨料透水混凝土进行坍落度、密度、抗压强度、抗弯强度、弹性模量、孔隙率、渗透系数、抗冻性试验。分析试验数据得出:随着总骨料中再生黏土砖骨料体积百分比增加,透水混凝土的坍落度和密度逐渐减小;当总骨料中再生黏土砖骨料体积百分比超过40%,透水混凝土的力学性能出现不同幅度的下降;透水混凝土的渗透系数和孔隙率与总骨料中再生黏土砖骨料体积百分比基本上没有相关性;透水混凝土的强度损失率和质量损失率都随着总骨料中再生黏土砖骨料体积百分比增加而增大,而且当再生黏土砖骨料体积百分比大于40%时呈现出加速增大的趋势。结果表明:在天然骨料中掺加适量再生黏土砖骨料配制透水混凝土是可行的,其透水性基本保持不变,但是,当总骨料中再生黏土砖骨料体积百分比超过40%时,透水混凝土的力学性能和耐久性受到很大的影响。

In order to study the application of recycled aggregates （RA） produced by mechanical shredding from discarded clay bricks in pervious concrete.6 groups of recycled aggregate were prepared according to the percentage of recycled clay brick aggregate in total aggregates and the basic performances of 6 groups of recycled aggregate were tested firstly.Then experiments about slump, density, compressive strength, elasticity modulus, flexural strength,permeability coefficient were conducted, including freezing and thawing cycle tests.The test data indicated that, with the increasing of clay brick aggregates percentage in total aggregates, slump and density of pervious concrete decreases.When clay brick aggregates percentage is greater than 40%, the mechanical properties of pervious concrete appeared different amplitude decreased.Pervious concrete permeability coefficient and total void ratio didn＇t change with the increasing of clay brick aggregates percentage.Strength loss rate and mass loss rate of pervious concrete increase witht the increasing of clay brick aggregates percentage, and when the percentage of clay brick aggregates greater than 40% showing a trend to accelerate the increase.The results showed that adding amount of recycled clay brick aggregate in the natural aggregate to making pervious concrete is feasible, its permeability remained basically unchanged, however, the mechanical properties and durability of porous concrete are greatly affected when the percentage of recycled clay brick aggregate is more than 40%.