Effect Of Fly Ash And Silica Fume On Properties Of Recycled PP Plastic Mortar

Plastics are widely used in all walks of life for their excellent properties.In recent years,China has become the largest consumer of plastics.At the same time,a lot of plastic waste has been produced.Traditional burying and burning not only pollute the environment，but also cause a lot of waste resources.It is one of the feasible methods to break waste plastics into plastic particles to replace aggregate in whole or in part to make plastic concrete or mortar,which can not only effectively use waste plastics,protect the environment,but also alleviate the problem of shortage of river sand resources in China,with good economic and social benefits.Plastic concrete is a new type of building material developed rapidly in recent years.Because of the low density and good elasticity of plastic particles,it has the characteristics of light weight and good toughness.At the same time,because of the incorporation of plastic particles,its mechanical strength decreases and its shrinkage deformation increases,which becomes an important reason to limit its application.In order to promote the wide application of plastic concrete,this paper uses the method of adding fly ash and silica fume to solve the problems of low mechanical strength and large shrinkage deformation of plastic concrete.The effects of fly ash and silica fume on the workability,physical properties,mechanical properties and shrinkage properties of recycled PP plastic mortar were studied by experiments,and the optimum content of fly ash and silica fume was determined.The results show that:(1)Fly ash alone can improve the working performance of plastic mortar,increase its compactness and improve its later strength.At the same time,the addition of fly ash reduces the shrinkage of plastic mortar,the larger the content is,the smaller the shrinkage is.The best dosage is 10%～15%.(2)The single addition of silica fume can reduce the working performance of plastic mortar,increase its compactness,and improve its compressive and flexural strength.At the same time,the addition of silica fume will increase the shrinkage of plastic mortar,and the larger the amount of silica fume is,the larger the shrinkage is.The optimum content of silica fume is 7%～10%.(3)The composite of fly ash and silica fume can reduce the working performance of plastic mortar,not only improve its early strength,but also improve its later strength,but also increase the self shrinkage and dry shrinkage of plastic mortar.The best content of silica fume and fly ash is 15%fly ash and 7%silica fume.The influence of fly ash and silica fume on the properties of recycled PP plastic mortar and the optimum content of fly ash and silica fume obtained in this paper have certain reference value for promoting the wide application of plastic concrete.Figure[45]Table[14]References[95]...