骨料及水灰比对透水混凝土性能的影响

为了研究骨料粒径及水灰比对透水混凝土力学特性及透水性影响,分别选取了骨料粒径2.5～6 mm、6～10 mm、10～16 mm以及16～20 mm四种范围单一级配碎石,制作了水灰比在0.25～0.34范围内的透水混凝土试样。通过单轴压缩试验及透水系数测试试验,得到了不同水灰比及不同粒径范围的透水混凝土试样应力应变曲线、抗压强度、峰值应变、吸收功及透水系数等力学及物理性能,分析了骨料粒径、水灰比对材料抗压强度、吸收功及透水系数等影响,并在试验结果基础上,建立了材料抗压强度同透水系数之间关系。结果表明:骨料粒径为2.5～6 mm、6～10 mm、10～16 mm透水混凝土抗压强度、应变峰值、吸收功在水灰比0.25～0.31范围内,随水灰比的增加而增加,当水灰比超过0.31时,随着水灰比增加而减小;材料的透水系数随着水灰比的增加而减小;材料的抗压强度同透水系数之间近似服从线性关系。研究成果可为透水混凝土配合比设计提供借鉴作用。

Influence of aggregate and water-cement ratio on the pervious concrete performance

To study the influence of aggregate particle size and water-cement ratio on the mechanical properties and water permeability of permeable concrete，a one-grade gravel with four-size aggregates of 2. 5 ～ 6 mm，6 ～ 10 mm and 10 ～ 16 mm、16 ～ 20 mm was selected to make permeable concrete samples with water-cement ratio in the range of 0. 25 to 0. 34． The mechanical and physical properties including stress-strain curve，compressive strength，peak strain，absorbed energy and water permeability coefficient of the permeable concrete samples were obtained by uniaxial compression and permeability coefficient test，and the effects of aggregate size，water-cement ratio on compressive strength，absorbed energy and permeability coefficient were analyzed． The relationship between the compressive strength of the material and the permeability coefficient was established based on the experiment results． It is shown that the compressive strength，strain peak and absorptive energy of the permeable concrete with the aggregate size increases with the increase of water-cement ratio in the range of 0. 25 ～ 0. 31，but decrease with the increase of water cement ratio when water cement ratio exceeds 0. 31． The permeability coefficient of material decreases with the increase of water cement ratio，and compressive strength of the material exhibits an approximate linear proportional relationship with the permeability coefficient． These conclusions can provide reference for the design of the pervious concrete mix ratio．