多因素对透水混凝土基本性能影响的试验研究

Experimental study of multiple factors on the basic properties of pervious concrete

由于透水混凝土胶凝材料用量大导致成本高,因此为了降低成本,考虑采用粗砂替代部分胶凝材料,通过正交试验,研究粗砂掺量、硅灰掺量、水胶比、减水剂因素对透水混凝土抗压强度、有效孔隙率和透水系数的影响。试验结果表明:随着粗砂的掺入,透水混凝土抗压强度下降,透水系数显著上升;随着硅灰掺量和减水剂的增加,抗压强度先上升后下降,有效孔隙率和透水系数下降不显著;随着水胶比的增大,抗压强度先上升后下降,有效孔隙率和透水系数均下降。当粗砂掺量、硅灰掺量、水胶比和减水剂分别为6%,6%,0.28和1.7%时,透水混凝土综合性能最佳。当粗砂掺量低于9%时,胶凝材料用量有所下降,透水混凝土有较高的强度和良好的透水性。

The large amount of cementitious materials used in pervious concrete resulted in high cost.In order to reduce the cost,this study proposed to replace part of cementitious materials with coarse sand.Through orthogonal experimental design method,the effects of factors like the content of coarse sand and silica fume,water-binder ratio and water reducing agent on the compressive strength,effective porosity and water permeability coefficient of pervious concrete were studied.The test results show that with the incorporation of coarse sand,the compressive strength of pervious concrete decreases and water permeability coefficient rises significantly.With more silica fume and water reducing agent added,the compressive strength first increases and then decreases,while the effective porosity and water permeability coefficient decrease slowly.As the water-binder ratio increases,the compressive strength first increases and then decreases,while the effective porosity and permeability coefficient both decrease.When the content of coarse sand,the content of silica fume,the water-binder ratio and the water reducing agent are 6%,6%,0.28 and 1.7%respectively,the comprehensive performance of the pervious concrete reaches its optimal state.When the content of coarse sand is lower than 9%and part of the cementing material is replaced,the pervious concrete has great compressive strength and water permeability.