Waste Ceramic Aggregate Concrete.Experimental Study On Compressive Strength And Permeability

Permeable concrete,as an environmentally friendly material,has a positive effect on solving environmental problems in the process of urban development.It can also reduce the environmental burden caused by the rapid development of the city and promote the harmonious coexistence of society and nature.As a large developing country,China has the world's largest amount of ceramics produced and used every year.Therefore,the amount of waste ceramics produced is also considerable.Improper disposal of waste ceramics causes serious environmental pollution.On the other hand,the rapid increase in the volume of urban construction caused by rapid urbanization has triggered a lot of environmental problems caused by the exploitation of sand and gravel.At the same time,there are also shortages of sand and gravel resources in some areas.In this study,the reuse of waste ceramics was combined with the preparation of pervious concrete.Through the research on the mix ratio design and preparation process parameters,the preparation method of waste ceramic aggregate permeable concrete was sought to alleviate the above environmental problems and the shortage of building aggregate resources..The main research work and conclusions are as follows:1.The basic properties of waste ceramic aggregates were studied.The particle size distribution of the waste ceramic aggregate after crushing can be controlled within the range of coarse aggregate(5-10 mm).It is theoretically feasible to consider the use of waste ceramic aggregates instead of coarse aggregates in terms of particle size distribution.The water absorption and porosity of waste ceramic aggregates are higher than that of gravel aggregates,and their bulk density and apparent density are lower than those of gravel coarse aggregates.2 Waste ceramic aggregates were prepared by replacing coarse aggregates of raw stone materials with different substitution ratios(50%,60%,70%,80%,90%),and the compressive strength was tested.The test results showed that: The compressive strength of concrete gradually decreases with the increase of the substitution rate of waste ceramic aggregates;when the substitution rate reaches 70%,the decrease rate increases significantly,and the compressive strength of the prepared permeable concrete is 29MPa(see related literature).The compressive strength of non-motorized permeable pavement is about 25 MPa.The replacement rate for this experiment is 70%.3.When the replacement ratio of waste ceramic aggregates is 70%,different water-cement ratios(0.25,0.3,0.35,0.4,and 0.45)are used to prepare waste ceramic aggregate permeable concrete.The results show that: with the increase of water-cement ratio The compressive strength of pervious concrete shows an upward trend.The compressive strength reaches a maximum of 29.42 MPa when the ratio of water to cement reaches 0.35.With the further increase of water-cement ratio,the compressive strength tends to decrease,and the phenomenon of backfilling bottom appears.4.The replacement ratio of waste ceramic aggregates was 70%,and the water-cement ratio was 0.35.When the pervious concrete target porosity is in the range of 15%-22.5%,its compressive strength and permeability can reach the target requirements.5.The 1% diluted KH-570 coupling agent was used to impregnate the waste ceramic aggregate and the compressive strength of the waste ceramic permeable concrete before and after immersion was compared.The results showed that the ceramic aggregate after the coupling agent infiltrating treatment prepared the compressive strength of the permeable concrete.Strength increased by 13.6%,flexural strength increased by 11.7%,actual porosity decreased by 6.2%,and permeability coefficient decreased by 11.7%.Therefore,when using the coupling agent to reinforce the permeable concrete of the waste ceramic aggregate,the relationship between the strength and the permeability coefficient should be considered as a whole.6.The regression curve equation between the strength,target porosity and permeability coefficient of permeated concrete with waste ceramic aggregates was studied.The permeation performance was improved while ensuring the mechanical properties of pervious concrete.