Preparation And Properties Of Fly Ash And/or Steel Slag-HDPE Composites

With the continuous improvement of China’s highway construction,the demand for pavement repair materials is also increasing.Currently,the commonly used restoration materials are mainly fast-setting cement and the use of bitumen for post-repair.The fast-curing cement has a high cost and a lower strength at a later stage.As for the repair effect,the repair time of asphalt is relatively long and has a great impact on road traffic.HDPE plastic is an essential consumable in production and life.Due to its good fluidity and rapid solidification in the molten state,it can be considered as a pavement repair material,but the traditional HDPE material,heat resistance and mechanical properties have yet to be improved.Therefore,this study proposes adding solid industrial waste Fly Ash,steel slag,and construction waste as fillers for plastics to HDPE.On the one hand,it improves the mechanical properties of the material.On the other hand,the addition of solid waste can reduce the concentration of the use of vinyl material and achieves the purpose of resource conservation,and at the same time,it also enables high-value use of solid waste.The main contents of this study are as follows:(1)Preparation and modification of FA-HDPE composite materials.Firstly,the effects of FA particle size and blending amount on the properties of the composites were investigated.It was found that increasing the FA particle size would increase the tensile strength,bending strength,and impact strength of the material first and then decrease.The increase of FA content will make the tensile strength of the material appear higher first and then decrease,and the tensile strength of FA content 10% is the best,reaching 12.83 MPa,which has reached the technology in GB/T 11115-2009.Claim.In order to further improve the mechanical properties of composite materials,this topic with silane coupling agent surface modification treatment of FA,found when using 3% of silane coupling agent modified FA,FA-HDPE composites were the best mechanical properties,tensile strength,impact strength 14.86 MPa,69.23 MPa,respectively,compared to before modification increased by 10.89% and 25.87% respectively.(2)Preparation of steel slag-HDPE composite materials and construction waste-HDPE composites.The steel slag-HDPE composite materials and the construction waste-HDPE composite materials were prepared by the pressure forming technology.First studied the heating temperature,heating time and pressure load and steel slag adding amount on the material density and compressive strength,the influence of steel slag content was 80% of screening out the best conditions for heating temperature 200℃,the heating time for 20 minutes,25 MPa pressure load,compressive strength of the block and now is 36.9 MPa.And further research of steel slag aggregate gradation and different aggregate types to block the effect of compressive strength and abrasion resistance,found in the closest packing of the same particle size gradation of steel slag to replace steel slag,can make the compressive strength of materials have greatly improved.The composite materials can be prepared by replacing steel slag with construction waste as aggregate,and the compressive strength of the materials is the largest,reaching 31.5MPa when the mixed amount of construction waste is 80%.In addition,the composite materials prepared by the heating forming method solidified quickly,without the need of late maintenance and excellent wear resistance.