Research On The Application Of Geogrid Ecological Concrete In Soil Erosion Restoration Project

The Loess Plateau is named for its large surface area covered with loess.The origin of more than 200 rivers,such as Qingshui River and Fen River,is in the Loess Plateau.In summer,rainwater washed the loess and carried a large amount of sediment into the river channels.In addition,human beings’ unreasonable use of the land has led to serious soil and water loss on the Loess Plateau,resulting in bare and barren land,scattered vegetation distribution and low coverage rate.In this paper,the application of geogrid ecological concrete in soil erosion remediation project was studied,which was based on ecological concrete and geogrid.The porous structure of ecological concrete was used to plant vegetation,and the good bending and tensile performance of geogrid was used to strengthen the ecological concrete,so as to maintain the integrity of the ecological concrete plate and jointly achieve the purpose of preventing soil and water loss.Firstly,geogrid ecological concrete was prepared,and the best mixture ratio of geogrid ecological concrete was designed by detecting its mechanical properties and porosity.Then,with the optimal mix ratio of geogrid ecological concrete,the engineering test model of "geogrid ecological concrete slab + soil layer + vegetation" was made by pouring geogrid ecological concrete in the outdoor engineering test site to study the influence of various factors on soil erosion and the vegetation growth effect of geogrid ecological concrete.Through the experimental research,the following conclusions were drawn:(1)In this paper,by analyzing the water cement ratio,species,aggregate size of geogrid geogrid ecological concrete compressive strength,flexural strength,the influence of found in the water cement ratio and aggregate size equal,after adding geogrid of concrete strength are higher than did not join the geogrid concrete strength,compressive strength,flexural strength,the mean can be increased by about 10% and20%,respectively.The strength of ecological concrete with 1.5cm mesh side length is higher than that of ecological concrete with 3.5cm mesh side length plastic geogrids.With the increase of water-cement ratio,the strength of geogrid ecological concrete generally increases at first and then decreases,indicating that the strength of geogrid ecological concrete has a peak value with the change of water-cement ratio.The strength of geogrided ecological concrete decreases with the increase of aggregate particle size.(2)By analyzing the influence of water-cement ratio,geogrid type and aggregate particle size on the porosity of geogrid ecological concrete,it is found that with the increase of water-cement ratio,the porosity of geogrid ecological concrete specimens in general also presents a trend of first increase and then decline.The porosity of geogridged ecological concrete increases with the increase of coarse aggregate particle size.The porosity of ecological concrete with 3.5cm meshwork side plastic geogrids is about 10% higher than that of ecological concrete with 1.5cm meshwork side glass fiber geogrids.(3)Considering the results of mechanical properties test and porosity test of geogrid ecological concrete,the final selection of water cement ratio of 0.35,aggregate grading of 10-20 mm gravel as coarse aggregate,mesh side length of 1.5cm glass fiber grid and mesh side length of 3.5cm plastic grid as reinforcement materials,concrete in the outdoor forming,The outdoor model engineering test of geogrid ecological concrete was carried out.(4)The model engineering test takes the type of slope,vegetation and geogrid as variables to observe and calculate the amount of soil loss and the number of gullies after erosion,so as to study the impact on soil and water loss.The research shows that with the increase of slope,the soil and water loss of the upper soil of geogrid ecological concrete is greater,and the soil and water loss of the upper soil of geogrid ecological concrete is the least in the three slope types of gentle slope,steep slope and trapezoidal slope.The soil and water loss on the upper part of geogrid ecological concrete with vegetation was 15.6% less than that without vegetation.The soil erosion with geogrid is 32.1% less on average than that without geogrid,and the soil erosion with plastic geogrid is 8.6% less on average than that with glass fiber geogrid.(5)Tall fescue and ryegrass were planted on top of the ecological concrete of the outdoor model geogrids.From the perspective of vegetation growth,vegetation density and vegetation coverage on gentle slope were the highest,followed by trapezoidal slope and steep slope.After 7 days of treatment,the plant height on each slope was basically the same.After 28 days of treatment,the plant height on gentle slope and trapezoidal slope was significantly higher than that on steep slope,19.0%and 16.4% higher,respectively...