| The regeneration concrete solves environmental pollution of waste brick aggregates,waste concrete and brick waste mixed recycled aggregate.Self-compacting concrete technology is utilized to achieve weight pouring itself dense,but it uses more powder and increases production costs.Steel slag is steel industrial waste residue which is discharged of10%-15% with making steel.It causes serious environmental pollution and waste of land resources when a large amount of steel slag is dropped in farmland. Steel slag composition is similar to cement, and it has the hydration of C3 S and C2 S composition,so it has a certain activity.It is feasible under the condition of steel slag.It's available to replace cement when conforming to the standard of "used in the cement and concrete in steel slag powder".It is a very meaningful topic to research how to produce the recycled aggregate of self-compacting concrete with steel slag(RASCCSS) by mixing with steel slag cement materials and recycled aggregate via comprehensive recycled concrete technology and self-compacting concrete technology.Based on the conclusion of 30% replacement of recycled aggregates without any influence on the concrete working performance,this article studies the concrete of content of the loss,working performance and basic mechanics performance with different replacement of steel slag.On this basis, article give the mixing design method of RASCCSS.Through further studying, the steel slag plays a role in the component performance of the bending menbers, shear menbers, eccentric compression menbers.And this article presents a constructive method of RASCCSS for slope roof.In this paper, the main conclusions are as follows:(1)Mixing with steel slag increased the liquidity of recycled aggregates self-compacting concrete, which is due to the low activity of steel slag requireless water to plastic state. When a certain amount of water is added, the larger the amount of cement replaces, the greater the fluidity is. Unhydrated slag can act as a filler to fill the cement particle size distribution, also enhance the mobility and filling of recycled aggregate self-compacting concrete.(2)The workability of fresh concrete declines with the extension of time. Adding the right amount of polycarboxylate superplasticizer can restore the slump flow. The gradual loss of slump flow is expressed by a formula proposed in this paper, which can be a reference on the evaluation of gradual loss of slump flow of RASCCSS.(3)Early strength of RASCCSS wil be decreased, when steel slag replaces cement. Theearly strength still satisfy form removal strength under 50% substitution rate of slag. Steel slag will significantly promote the growth of the late strength, but with the continued increase in the incorporation of slag, the late strength of growth rate is stabilized.(4)The splitting tensile strength, axial compressive strength and modulus of elasticity of RASCCSS will be increased,when the steel slag replacement is from 0% to 10%.Expressions of splitting tensile, axial compressive strength andelastic modulus to compressive strength of RASCCSS are proposed in this paper.(5)The ultimate bearing capacity and failure modes of flexural members, shear members and compression members which are made of RASCCSS is similar to self-compacting regeneration coarse aggregate concrete member.The ultimate strength was increased when the steel slag replacement is from 0% to10% and the calculation formulas of current design standard can be used of flexural members, shear members and compression members which are made of RASCCSS.Early strength of RASCCSS wil be decreased,when steel slag replace cement. The early strength still satisfy form removal strength under 50% substitution rate of slag.Steel slag will significantly promote the growth of the late strength,but with the continued increase in the incorporation of slag, the late strength of growth rate stabilized.(6)Initially established the frame of RASCCSS construction method for slope roof. |
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