| China is a big producer of ceramics.Ceramics are solid materials produced by clay after being fired at high temperature,and the biodegradation period is very long.A large amount of ceramic waste is stored in the garbage treatment plant,which not only occupies a large amount of land resources,but also has an impact on the ecological environment.On the other hand,a large number of infrastructure projects in Guangdong province have also strained the supply of river sand.In view of the situation that waste ceramics cannot be treated and river sand is in short supply,this paper presents a method of reuse of waste ceramics.Was studied by experiment and finite element simulation,the regeneration of ceramic aggregate concrete under normal temperature and after high temperature mechanical properties,was obtained under the condition of different temperatures of regenerative ceramic optimal replacement rate,thus find processing method for a large number of hoarding of ceramic waste,at the same time solve the problem of river sand resource shortages,in line with the green concept of sustainable development.The basic material properties of discarded ceramics as concrete aggregate were studied.Compare ceramic aggregate with natural aggregate to find out the difference between the two properties.The results show that the fineness modulus of ceramic fine aggregate is larger,the water absorption is higher,the moisture content is normal,and the density is lower than that of ordinary river sand.Ceramic coarse aggregate has smaller particle size,slightly higher water absorption rate,normal moisture content and lower density than ordinary gravel.The mechanical properties of recycled ceramic mortar and recycled ceramic concrete at room temperature were studied.Through experimental analysis,the addition of discarded ceramics can effectively alleviate the degree of concrete strength decline caused by the increase of water-cement ratio.The scheme that only waste ceramic fine aggregate is added to waste ceramic recycled concrete is more economical in terms of cost and easier to realize in terms of construction technology.Waste ceramic aggregate can play an internal curing role in cement hydration process.With the increase of the replacement rate of discarded ceramics,the strength of reclaimed ceramics mortar increases continuously.The strength of recycled fine aggregate concrete of discarded ceramics first rises and then decreases,the compressive strength reaches the maximum when the replacement rate is 70%,the splitting tensile strength reaches the maximum when the replacement rate is 60%,and the quality of the recycled fine aggregate concrete of discarded ceramics continues to decline.The possibility of caustic aggregate damage caused by waste ceramic aggregate is very small by rapid alkali aggregate test.Considering the characteristics of ceramic materials,the mechanical properties of recycled mortar and concrete after high temperature were studied.After high temperature burning,the strength of recycled ceramic mortar is constantly improved,and the microstructure of cement mortar is constantly changed from flocculent to spongy and clastic.The mass loss of waste ceramic fine aggregate recycled concrete after high temperature burning is lower than that of ordinary concrete.After 200 ℃,400 ℃ and 600 ℃ after high temperature burning waste ceramic fine recycled concrete aggregate and mechanics performance is better than that of normal concrete,and the regeneration of ceramic add basic had no effect on the elastic modulus of concrete.Based on the experimental results,the mesoscopic finite element model of recycled ceramic fine aggregate concrete was established.By loading the model,the results of compressive strength are obtained,which are basically consistent with the test results,thus proving the correctness of the meso finite element model of recycled concrete with waste ceramic fine aggregate.Based on this microscopic model,the range of replacement rate of discarded ceramics that was not done in the test was increased,and the curve of compressive strength changing with the replacement rate of discarded ceramics was obtained,indicating that the optimal replacement rate of discarded ceramics was 70%.In addition,the effects of material properties,gradation and interfacial transition zone on concrete strength are analyzed to provide a theoretical basis for subsequent related studies and practical engineering applications. |
