Study On The Properties Of Matrix Materials For Ecological Protection Of Rock Slope

As a new technology in slope treatment,vegetation slope protection replaces the traditional reinforced concrete surface layer with suitable substrate and engineering measures,and plants green vegetation on it to stabilize the slope and green the slope.Compared with the traditional slope,the vegetation slope protection adopts the substrate as the slope protection base.The construction procedure is simple and will not cause dust pollution to the surrounding environment.Spraying plant seeds in the substrate,and then the growing vegetation can not only maintain the stability of the slope,but also beautify the slope as a green landscape.For rock slopes,plants are difficult to grow on slopes,so the matrix layer is the key to ensuring the success of vegetation protection technology,which requires that the substrate layer can ensure its own stability and the water for the vegetation's growth.In order to select a reasonable substrate proportion,the effects of diatomite and straw on water circulation and mechanical stability of substrate were studied by means of permeation test,evaporation test,compaction test and triaxial test on the basis of reading and analyzing the relevant research at home and abroad.The main contents of the research include:(1)The effects of different proportion on the permeability,water holding capacity and evaporation characteristics of diatomite,straw and both when mixed into soil were studied by permeation test and evaporation test.The results show that both diatomite and straw can effectively improve the permeability and water holding capacity of soil.Generally,the water holding effect and the gain effect in permeability of diatomite are better than straw.At the same time,it was found that when the content of diatomite and straw was similarly mixed in the soil,the permeability coefficient decreased.The incorporation of diatomite and straw can not change the evaporation rate of soil,but because of the high initial moisture content,the steady evaporation stage of soil can be prolonged.When the straw content exceeds 20%,the soil evaporates at a nearly constant rate,which keeps the soil at a steady evaporation stage and improves the drought resistance of the soil.(2)The effects of different proportions of diatomite and straw on the mechanical properties of substrate were studied by compaction test and triaxial test.The results show that both diatomite and straw can effectively reduce the density of soil.The stress-strain curves of soil samples mixed with diatomite or straw belong to strain hardening type,and the failure of soil samples is plastic failure mode.When the content of diatomite exceeds 20%,the shear strength of the substrate can be effectively improved.When the content of diatomite is 40%,the shear strength is the highest,while the straw has no obvious improvement effect on the shear strength of the substrate.(3)On the basis of the above test results,further screening was carried out.Diatomite and straw were added into the soil at the same time to measure its shear strength.The results showed that once straw was added into the soil sample,its shear strength would be significantly reduced,and even though the straw content was very small,its effect on shear strength was still dominant.Because the rock slope requires a high shear strength of the matrix,the straw used in this test is not suitable as a modified material for the rock slope matrix.Finally,considering all aspects,in the selected test materials,when the soil content is 60%and the diatomite content is 40%,the properties of the substrate are optimal.