Performance Test Of Steel Slag-stone Concrete

In recent years,the discharge of waste residues in the steel industry is very serious.The discharge of waste residues not only reduces the economic benefits of the steel industry sector,but also requires the occupation of additional sites for stacking,resulting in a great waste of resources.In order to improve the current low utilization rate of steel slag as soon as possible,the recovery rate and reuse rate of steel slag must be improved.This article has mainly studied the feasibility of steel slag stone to replace traditional crushed stone coarse aggregate to prepare concrete,and conducted experimental research.Steel slag stone was used to replace crushed stone in a certain proportion to prepare steel slag stone concrete,and the differences between steel slag stone concrete and ordinary concrete in workability,mechanical properties,deformation performance and durability were compared.The best replacement rate of slag stone has been put forward and the economic benefit has been analyzed.In terms of working performance: the fluidity of concrete mixture with steel slag stone replacing crushed stone is lower than that of ordinary concrete.With the increase of replacement rate of steel slag stone,the slump of concrete decreases,and the time loss rate of slump increases.In terms of mechanical properties and deformation properties: after standard curing for 28 days,the compressive strength of steel slag stone concrete is greater than 30 MPa,but lower than that of ordinary concrete.With the increase of replacement rate of steel slag stone,the compressive strength of steel slag stone concrete increases first and then decreases when the curing period is not more than 14 days.When the curing period is 14-28 days,the compressive strength of steel slag stone concrete decreases.Compared with the ordinary concrete,the early tensile strength of the steel slag stone concrete is higher,but in the later stage,its strength is lower than that of the ordinary concrete.When the replacement rate of the steel slag stone is not more than 50%,its tensile strength can meet the requirements of C30 concrete.Similar to the tensile property of slag concrete,the addition of steel slag stone will weaken the resisting-folded strength of concrete,and the resisting-folded strength is less than that of ordinary concrete.When the replacement rate of steel slag stone is not more than 75%,the resisting-folded strength can meet the requirements of C30 concrete.The axial compressive strength of steel slag stone concrete is higher than that of ordinary concrete,and all meet the requirements of C30 concrete.The elastic modulus of steel slag stone concrete is higher than that of ordinary concrete,and the elastic modulus increases with the increase of replacement rate of steel slag stone.In terms of durability: in the carbonization test,the steel slag stone concrete showed better resistance to carbonation in the early stage of curing;as the replacement rate of steel slag stone increased,the carbonation resistance showed a tendency to increase first and then decrease.In the anti-chloride ion penetration test,the electrical flux of all steel slag stone concrete is higher than that of ordinary concrete;as the replacement rate of steel slag stone increases,the resistance to chloride ion penetration decreases.After comprehensive analysis of all aspects of steel slag stone concrete performance,it is recommended that the best replacement rate of steel slag stone is 25%.