混凝土砂基透水路面砖制备及物理性能测试

Precasting method and physical property test of sand-based concrete permeable pavement bricks

推广砂基透水砖是实现沙漠沙资源化的有效途径.以烘干砂为主要骨料、高标号水泥为粘结剂并采用静压成型工艺,研制出一种预制透水孔的混凝土砂基透水路面砖,并对所研制的透水砖进行了物理性能测试和造价分析.结果表明：（1）所研制的混凝土砂基透水砖抗压强度超出我国建筑材料行业标准Cc60透水砖的要求,抗压强度可达100 MPa.（2）预设的透水孔使混凝土透水砖的透水性超过行业标准,而且透水孔上小下大,不易堵塞,不影响人行步道的舒适性.（3）根据透水砖的抗压强度、透水性、保水性、造价等方面综合考虑,选取细砂率70%、水灰比0.34、孔隙率2%、添加水性氯丁胶（AN）的第20组作为高强透水砖优选方案,选取细砂率85%、水灰比0.30、孔隙率1%、无添加剂的第22组作为常用广场透水砖优选方案,用于后续产业化开发研究.（4）增加粗骨料可显著提高透水砖的抗压强度,透水砖的细砂率可控制在70%～85%.（5）添加合适类型和剂量的添加剂可提高透水砖的抗压强度.（6）除了第7、11、12、19组造价偏高以外,其余组次造价都在60～100元/m^2,与常规无砂混凝土透水砖价格接近,远小于市场上已有同类砂基透水砖的价格.

Promoting sand-based permeable brick is an effective way to recycle desert sand.A kind of sand-based permeable brick with precast permeable pores is developed.The brick is composed with roast sand as the aggregate and high-strength grading concrete as the binder,and is formed under static pressure.A series of physical performance tests and cost analyses are then conducted.The results are as follows：（1）Compressive strength of the permeable brick reaches up to 100MPa,which is highly above the requirement of Cc60 permeable brick in the Construction Material Industry Standard in China.（2）The pre-fabricated penetrating hole makes the permeability of the brick far ahead of the Construction Material Industry Standard in China.Moreover,it is not so easy to clog, and does not influence the comfort of the pavement,for the hole is so small in diameter on the top and large at the bottom.（3）Comprehensively considering the compressive strength,permeability,water retention,cost and so on,the following two schemes are chosen for future study：The 20th group is selected as the high-strength permeable brick,of which the fine sand ratio is 70%,the water cement ratio is 0.34,the porosity is 2%and the additive is the aqueous neoprene,in short AN;and the 22th group is more suitable to be used on the plaza pavement,of which the fine sand ratio is 85%,the water cement ratio is 0.30,the porosity is 1%,and no additive is added.（4）Increasing the coarse aggregate content could significantly augment the compressive strength of permeable brick.A preferable fine sand ratio is 70%-85%.（5）On the other hand,to mix an appropriate kind of additive with proper dosage is another way to enhance the brick.（6）Except higher cost of groups 7,11,12, 19,the cost of other groups is between 60-100Yuan/m^2,which is close to that of general no-sand permeable concrete brick,and far lower than that of the same kind of sand-based permeable brick.