Study On The Preparation And Properties Of The Building Muck Free Brick Products

With the acceleration of urbanization and the upgrading of urban construction in our country,the amount of construction waste residue is increasing day by day.However,we had not paid enough attention to the application of construction waste residue at present.The storage of construction waste residue will bring a series of problems,such as occupying a lot of land,polluting the surrounding environment,and directly affecting the appearance of the city.And there is no place to store the construction waste residue in the city.We need to be transported the muck to the suburbs to backfilling.However,in the process of transportation,a large amount of dust will be generated and enter the air with the wind,affecting the air quality and causing further environmental pollution.In terms of the management of construction waste residue,institutional building is still far from perfect,muck management department is only passive management,and few cities has systematic consideration on the reduction,recycling and reuse of muck.But the distribution of the construction waste residue is vast,and if it can be used efficiently,the social and economic benefits are incalculable.Not only can save the cost of transport,cleaning costs and handling costs,save a lot of land resources,but also can produce huge economic benefits.This article introduces the current status of the construction waste residue,summarizes the classification and curing principle of the curing agent,and has reviewed the research and development of the construction waste residue around the country.To solve above problems,using muck as the main raw material of unfired brick,the exploratory study on muck curing agent was carried out.X-ray diffraction analysis,Scanning Electron Microscope(SEM),Energy Dispersion Spectrum(EDS),sieve analysis,Liquid-plastic combine tester and compaction test were used to test and analyze the material composition,particle composition,liquid-plastic limit index and maximum dry density of muck.Then adding 10% curing agent to the muck,the muck are forming under 20 MPa pressure by homemade mould.Taking compressive strength as the index,the effects of water-solid ratio,cement,lime,fly ash,slag,silica fume,powder fortifier,starch,water-reducing agent,anti-mud agent,mixing time and curing method on its mechanical properties were investigated.In addition,the products that meet the requirements of MU15 and MU20 standards will be tested in terms of appearance quality,size deviation,water absorption,softening performance,anti-freezing performance,differential heat analysis and mercury porosimeter.The results show that: according to the requirements on "non-sintered waste tailings brick"(JC422-2007),the recommended ratio of the MU20 unfired brick requires is cement 69.93%,lime 17.49%,silica fume 5.58%,starch 7%,standard curing for 28 days,the strength is 20.50 mpa.The recommended ratio of the MU20 unfired brick requires are two kinds,respectively: 72% cement,18% lime,silica fume 6%,24 h,80℃ steam curing strength is 15.09 MPa and 72.94% cement,18.24% lime,silica fume5.82%,starch 3%,24 h,80℃ steam curing strength is 15.27 MPa.However,the water absorption and softening properties of the sample with starch were not up to the standard,and improvements are needed.