振动压实无砂多孔混凝土组成设计方法(英文)

采用浆体贯入度试验方法,研究了不同水粉质量比的水泥净浆、水泥粉煤灰浆体和水泥硅灰浆体粘稠度变化规律,分析了混合料拌和过程中浆体与集料的粘附状况以及振动压实下混合料浆体析漏情况,提出了适合振动压实工况的无砂多孔混凝土组成设计方法。分析结果表明:在混合料拌和过程中,随着浆体贯入度的增大,浆体在集料上的裹覆量先增大后减小,贯入度在20～40mm时的裹覆能力较强;在振动压实条件下,浆体不出现析漏且试件完整时,浆体贯入度在20～25mm之间;设计的孔隙率为21.8%的无砂水泥混凝土,试件内部孔隙均匀,28d抗压强度能够达到22.8MPa,抗折强度达到3.4MPa。

Design method of no-fines porous concrete composition based on vibration compaction

The viscosity change rules of cement pastes,cement fly-ash pastes and cement silica fume pastes with different water to powder ratios were studied by using paste penetration test.Paste adhesive capacity to aggregate and paste leakage condition were analyzed based on mixture mixing test and vibration compaction test,and the design method of no-fines porous concrete composition at vibration compaction condition was provided.Analysis result indicates that in the mixing process of mixture,the amount of paste adhered to aggregate increases firstly and then decreases with the increase of paste penetration value,and paste adhesive ability is great when penetration value is 20-40 mm.Penetration value is further narrowed to 20-25 mm to avoid paste leakage and specimen damage at vibration compaction condition.No-fines porous concrete with 21.8% void ratio is designed by using the method,pore distribution in specimens is uniform,and 28 d compressive strength and flexural strength can reach 22.8 MPa and 3.4 MPa respectively.9 tabs,8 figs,18 refs.