Study On The Mixture Ratio Design Of Recycled Aggregate Concrete With Mineral Admixtures Of Xinjiang Arctic Condition District

For a long time the traditional building industry production method basically can besummarized as extensive a high input, high pollution, low efficiency of the mode of production. Theservice life of concrete is long, but the use of decades or even a hundred years after the final will beremoved. With the Chinese western big development, Xinjiang construction industry is vigorousdeveloping. Therefore, the aggregate demand is growing, on the other hand, a lot of old buildingswill be demolished, the problems caused by increasingly prominent architectural garbage. Atpresent, Urumqi city construction waste are filled, or outer suburb stacked mode, but these twomethods both environmental pollution and waste of resources. Research and application of recycledconcrete technology is used, one can solve the waste concrete processing difficulties and ecologicalenvironment caused by damage; on the other hand, the construction waste recycling recycledaggregate instead of natural aggregate, can reduce the construction of natural aggregateconsumption, thereby alleviating the natural aggregate is becoming scarce pressure and reduce the alot of sand mining on the ecological destruction of the environment. In addition, the recycledconcrete mixed with mineral admixtures, as industrial waste, the rational use of it, is conducive tothe Protect environment, reduce the cost, but also can improve the mechanical properties anddurability of recycled concrete in a certain extent, has the environmental benefit and economicadvantages. Therefore, in the Xinjiang region to promote the use of mineral admixtures of recycledconcrete is a development trend in the future.On the basis of "recycled coarse aggregate for concrete"(GB/T25177-2010) will be recycledcoarse aggregate of different primary purpose and strength grade classification, for different kindsof regeneration of recycled concrete coarse aggregate by orthogonal experimental design, discussthe water cement ratio, replacement ratio of recycled aggregate and admixture s of regenerationeffect of workability and compressive strength for different categories; select the type of recycledcoarse aggregate production of recycled concrete, and mixed with different mineral admixturesmethod, comparing the different effect of mineral admixture on properties of recycled concreteengineering, design of orthogonal test with fly ash were obtained, the optimal slag lithium slag recycled concrete and the proportion; and the selection of matching representative in orthogonal testis discussed, the water cement ratio, replacement ratio of recycled aggregate and mineral admixtureamount of admixture effect on frost resistance of recycled concrete, the frost resistance grade andobtained the optimal ratio of each group; the last experiment was conducted to study the resistanceto water penetration of the optimal ratio of recycled concrete, the permeability rank each ratio.Research results show that, using the raw materials of Xinjiang and preparation of recycledconcrete suitable for local area. I kind of recycled coarse aggregate is class II recycled coarseaggregate stability, but the nature of original concrete of recycled concrete mixture ratio of recycledconcrete has little effect, class is class II regeneration of28day compressive strength of concrete is2.10%; with the recycled aggregate replacement rate increases, the recycled concrete strengthincreased first and then decreased, different water cement ratio decreased with different intensity,water cement ratio increased, decreased amplitude increases; fly ash for a class of optimum mixcombination is A4B3C2, namely the water cement ratio0.43, recycled aggregate replacement rate of70%, admixture replacement rate of15%, air entraining agent content is0.025%, the frost resistancegrade for F150, impermeability grade is S6; the optimal powder type material of recycled concretemixture ratio combination is A1B2C2, is a water cement ratio0.45, recycled aggregate replacementrate of50%, slag to replace rate of15%, air entraining agent content is0.025%, the frost resistancegrade is F≥200, impermeability grade S7; optimal lithium slag type material of recycled concretemixture ratio combination is A1B2C2, is a water cement ratio0.45, recycled aggregate replacementrate of50%, lithium slag replacement rate of15%, air entraining agent content is0.025%, the frostresistance grade is F≥200, impermeability grade of S7. Mineral admixtures can improve theengineering properties of recycled concrete to a certain extent. The performance of lithium slag onrecycled concrete improvements in the most significant effect, the optimal ratio of28daycompressive than natural concrete2.13%freeze-thaw cycles, the dynamic modulus of elasticity ofmass loss rate is higher than that of natural concrete5.59%200cycles of freezing,0.8MPainfiltration height less than the natural aggregate concrete11mm.