Study On Eco-material With The Function Of Infiltration And Storage

The rapid urbanization construction not only brings a series of ecological problems,but also produces large-scale construction waste.It is of great practical significance to make use of solid waste resources to serve the construction of sponge city.In this paper,waste sintered bricks are used as aggregate,using rice husk ash,copper mine tailings,bentonite and diatomite as fillers,the eco-material with the effect of infiltration,water storage,water purification and plant growth are prepared through the cementation of cement.Orthogonal and single factor experiments are adopted to explore the influence of aggregate size,filler content and water cement ratio on the strength,water permeability and water storage capacity of the material.The plant growth and water purification effect of the material are analyzed on the basis of the optimal mix ratio.The results show that:(1)Enhancing the water cement ratio and reducing the aggregate size can increase the compressive strength and water absorption rate of the material,but decrease the permeability coefficient;Enhancing the amount of fillers can increase the permeability coefficient and water absorption rate at the same time;The compressive strength for 28 days of the material decreases with the increase of rice husk ash and diatomite content,increasing copper tailings and bentonite content can increase the compressive strength for 28 days first then decrease.(2)It has been proved that the porous structure of the eco-material is developed and the water storage capacity is strong,which can satisfy the demand of plant growth.On the basis of mud mulching method,Akali grass and Agrostis stolonifera are the best choices for bank revetment and municipal greening respectively;The eco-material has certain water purification function,it can reduce the SS,COD,TP and NH3-N by more than 50%,20%,40%and 20%respectively,after the grass is cultured,the filtration capacity of COD,TP and NH3-N is stronger.(3)The micro analysis shows that after the fillers are combined with the cement,the density of the slurry is reduced.There is no new formation after the other fillers are combined with cement,except for diatomite.The active SiO2 content and the dispersing and diluting effect of non active substances of the fillers on cement are the main factors that affect the strength of the material.From the perspective of morphology,the surface pore structure of rice husk ash,copper tailings and other fillers is rich,which can improve the water storage capacity of the material through capillary channel,chemical adsorption and surface physical adsorption.(4)The main properties of the eco-material with rice husk ash,copper tailings/bentonite and diatomite as fillers are summarized,the group with rice husk ash as filler has the highest strength,the best effect of water storage and purification,which is most suitable for auxiliary road facilities in sponge city.The other two groups have the strongest water permeability and better planting effect,which are suitable for bank revetment.