Experimental Study On Aerated Concrete Block Preparation With Granite Waste

With the rapid development of economy and the increasing construction market demand for stone materials,the stone industry in China has achieved great progress.Granite is widely used for its high strength, hard texture, solemnappearance and so on.The mining and processing industry of granite minerals have gained great development.However,at the same time of vigorousdevelopment, there are have also occurred someenvironment problems, such as the corner waste accumulation, processing dust, cooling liquid,which has endangered the health of the surrounding people and seriously hampered the healthand sustainabledevelopment of the granite industry.With the world’s energy-resource situation increasingly serious, saving energy, reducing emission has become a basic national policy of China.The implementation of the reform of wall materials and the concept of green building put forward new requirements for building energy saving.The porous structure of the aerated concrete block makes it havethe characteristics oflight weight, good thermal insulation performance and so on,which meet the requirements of the new pattern walling materials and promotes extensive promotion and use of aerated concrete blocks.With the increase of the demand of the building project to the aerated block, the main material of the traditionalautoclaved aerated-concrete block, thefly ash is also gradually emerging. Analysis show that the chemicalcomposition of the granite ore is similar to that of the fly ash, which contains a large amount of Si02. As a result, granite powder instead of fly ashto produce autoclaved aeratedconcrete block may be provided.This methodnot only achieve the waste resource of secondary utilization and solve the growing granite waste material possession of land resources, economic resources waste and environmental pollution. At the same time, but alsoreduce the cost of production of aerated concrete block, ease the shortage of fly ash, which accords with the building energy saving,sustainabledevelopment and environmental protection requirements.This thesis refers to theautoclaved aerated concrete block industrial production process, using the method of laboratory to produce aerated blocks. In a word, this thesiswill mainly demonstrate the following aspects:1) The granite powder instead of fly ash is used as the siliceous material in autoclaved aerated concrete block production. In the reference to the formulationof the production of autoclavedaerated concrete block with fly ash, this thesis studies the effects of each component content on the strength of aerated block, ultimately determine the optimal mix proportion. In the end, the aerated concrete block with a dry density of 638 kg/m3 and compressive strength of 3.92 MPa is produced.2) In this thesis, the effect of the additive granite aggregate and air-entraining admixture on the performance of the autoclaved aerated concrete block was further studied. The resultsshow that the strength-to-weight ratios ofaerated concrete block with additive granite aggregate did not achievethe desired effect, but the additionof air-entraining admixture aerated block strength reached 7.2.The resultsshowed that the two factors had the opposite effect on the pore structure of the aerated block.3) In this thesis, the durability of the test block of aerated concrete produced by this formulation. The results show that the frost resistance property of the aerated concrete block with granite powder meets the requirements and the strength lossrate is lower than 10%.Among them, the frost resistance property of aerated concrete block with air-entraining admixture is the best.4) This thesis makes a quantitative analysis of the cost of autoclaved aerated concrete block by using granite powder and compares with the cost of traditional aerated concrete blocks, then the economic analysis is carried on.