Performance Experimental And Application Study On High-titanium Blast Furnace Slag No-sand Concrete

In this paper,expounded the development and research the current situation at home and abroad of no-sand concrete,by experiment,study the composition material of high-titanium blast furnace slag no-sand concrete,this paper obtains the basic physical and mechanical properties of the composing materials,which provide the standard data for engineering applications.By expounding the determination methods of the performance indicators of high-titanium blast furnace slag no-sand concrete,this provides a theoretical basis for the experiment.Design orthogonal test,to study the influence factors with the performance of high-titanium blast furnace slag no-sand concrete.In this paper,the volume method is used to the mix proportion design of high-titanium blast furnace slag no-sand concrete,which proposes the calculation method of the mix proportion design for the high-titanium blast furnace slag no-sand concrete.According to the characteristics of the high-titanium blast furnace slag no-sand concrete being skeleton-pore structure,this paper researches the influence of aggregate gradation,water-cement ratio,ash set ratio,fly ash content,cement strength grade and admixture dosage on the high-titanium blast furnace slag no-sand concrete of compressive strength,porosity,permeability coefficient,force-displacement characteristics,splitting strength and stretchability.The results show that,when the porosity between 20%-25%and a certain strength requirements are satisfied,the optimal mix ratio of the high-titanium blast furnace slag no-sand concrete is that the water-cement ratio is about 0.5,the cement-aggregate ratio is about 1:5.When the coarse aggregate is 4.75?9.5mm,the compressive strength of the high-titanium blast furnace slag no-sand concrete is 11.01 MPa.When the coarse aggregate is the continuous-gradation particle size between 4.75?19mm of the high-titanium blast furnace slag gravel,The 28d compressive strength of the high-titanium blast furnace slag no-sand concrete reached 8.48MPa,its effective porosity is 23.14%,its total porosity is 36.18%,its permeability coefficient is 4.26cm/s;when the fly ash is about 20%,the 28d compressive strength of the high-titanium blast furnace slag no-sand concrete reaches 8.75MPa;its 14d compressive elastic modulus is 1.51×104MPa,its 28d compressive elastic modulus is 1.62×104MPa,and its splitting strength is 1.402MPa;When the admixture content is about 0.8%,its 28d compressive strength reaches 9.23MPa;the above indicators reaches the optimal value.The experiment results also show that the flexibility of the high-titanium blast furnace slag no-sand concrete changes slowly in the earlier stage and changes greatly in the later stage.Finally,by comparing and analyzing the actual engineering examples,it is feasible to promote the application of the high-titanium blast furnace slag no-sand concrete in the project of roads,sidewalks,parking lot and slope support.