Research On The Performance And Application Technology Of Green-growing Ecological Concrete

Infrastructure construction has caused serious damage to the slope ecosystem,in order to overcome this defect,the technology of green-growing ecological concrete slope protection was introduced into the research.This paper takes the ecological protection of highway slope in the north as the background,the mixture ratio,physical and mechanical properties,water permeability,durability and vegetation growth were studied.The conclusion is as follows:(1)In the study of mix proportion design,the design parameters are determined as 28-day cubic compressive strength ≥ 8Mpa,the effective void ratio should be controlled at 20% ~ 30%,and alkalinity in void is 7.0 ~ 9.0;volume method is used to calculate the mix proportion.(2)Through the analysis of variance of orthogonal test,for the 28-day cubic compressive strength index: the target void ratio is the most significant,followed by mineral admixture ratio,water cement ratio and aggregate size are not significant,the optimization scheme is that aggregate size is 13.2-16 mm,target void ratio is 22%,water cement ratio is 0.3,mineral admixture ratio is 10%;for the effective void ratio index: the target void ratio has the most significant influence,followed by water cement ratio,but aggregate size and mineral admixture ratio have no significant influence,the optimization scheme is that aggregate size is 19-26.5mm,target void ratio is 28%,water cement ratio is 0.27 and mineral admixture ratio is 30%;for the pH value index: the mineral admixture ratio has a significant impact,but other factors have no significant impact,the optimization scheme is that aggregate size is 16-19 mm,target void ratio is 28%,water cement ratio is 0.33 and mineral admixture ratio is 30%.(3)Through the study of physical and mechanical properties,the 28-day compressive strength decreases with the increase of aggregate size,target void ratio and mineral admixture ratio,and increases first and then decreases with the increase of water cement ratio;the effective void ratio increases with the increase of the target void ratio,and is slightly smaller than the target void ratio;and the effective void ratio decreases with the increase of water cement ratio;the pH value decreases with the increase of mineral admixture ratio,which shows that the addition of fly ash has a certain effect of reducing alkali,but still can not meet the needs of plant growth,through studying a large number of documents,the following dealkalization treatment was carried out by mixing ferrous sulfate in the nutrient base.(4)Through the study of water permeability,in order to meet the requirements of slope ecological protection,the water permeability coefficient is required to be ≥ 1.0cm/s.It is found that the three optimization schemes have good mechanical properties and water permeability,and the water permeability coefficient increases with the increase of void ratio,especially the effective void ratio.(5)Through the study of frost resistance durability,the strength loss rate and quality loss rate increase with the increase of freeze-thaw cycle times,and the quality loss rate index can more accurately evaluate the frost resistance of ecological concrete;three groups of optimization schemes can basically resist about 100 times of freeze-thaw cycle,the frost resistance is good,and the freeze-thaw effect of the optimization scheme Y3 is the best.(6)Through the study of vegetation,Festuca arundinacea was selected as the slope protection plant,the nutrient base was prepared according to the quality ratio,and the wet filling was used for vegetation.The results show that the vegetation growth is in good condition,and has good effect of soil consolidation and slope protection,landscape greening.The compressive strength and water permeability coefficient of eco concrete after planting are lower than that before planting,and the water permeability of optimization scheme Y1 is poor when the planting age reaches 28 days,which is difficult to meet the index requirements;the pH of nutrient base increases with the growth of the planting age,but the increase is not large,which can meet the planting requirements.Among the three optimization schemes,Y3 of vegetation growth effect is the best,and Y3 is recommended in engineering application.