Research Of New Structure Form Of Gravity Ecological Retaining Wall Suitable For Reservoir Lifting Zone

In the construction of water conservancy projects in China,in order to avoid the instability of the slope in the reservoir area,it is usually necessary to build a retaining structure.Because of its simple structure,fast and convenient construction,gravity retaining wall has become one of the commonly used retaining structures in the reservoir area.In recent years,China’s infrastructure construction towards the direction of green ecology,the ecological construction of buildings put forward higher requirements.The traditional gravity retaining wall of water-level-fluctuating zone mostly uses concrete or mortar block stone,which can play a supporting function,but does not have the greening effect of ecological landscape.The color of the retaining wall is gray,which is not harmonious with the environment around the water-level-fluctuating zone.In view of this,this paper takes a gravity retaining wall in the Three Gorges Reservoir area as the research object,and the perennial climbing tiger is used as the attached vertical greening method of greening plants.According to the growth characteristics of the climbing tiger,a new type of gravity ecological retaining wall structure suitable for the support of the fluctuating zone is designed.The finite difference method is used to carry out the stress and strain calculation of the retaining wall,and the stress and deformation of the new structure of gravity retaining wall are obtained.On this basis,the stability coefficients of the retaining wall against sliding and overturning are determined through theoretical analysis.In order to ensure that the climbing tiger can grow normally under the condition of high water level,not to drown and die,a new structure form of gravity ecological retaining wall is carried out to avoid the function test of plant growth under high water level,which verifies the scientificity and rationality of the structure.The specific research results are summarized as follows :(1)In order to prevent the reservoir water from pouring back under the condition of high water level,submerged the rhizome of Climbing Tiger,and adversely affected the growth of Climbing Tiger,this paper intends to develop a new structure with water insulation function and greening,and through the planting test of Climbing Tiger in the outdoor water and gas exchange and sunshine isolation,to explore the survival of Climbing Tiger in the retaining wall only with the soil behind the wall for water and gas exchange and no light.The test results show that the climbing tiger can still grow under the condition of water-air exchange and long-term shading,which provides a design basis for the research and development of new structural forms of gravity ecological retaining wall in reservoir drawdown zone.(2)Based on the shading planting experiment of the climbing tiger,a gravity ecological retaining wall is designed to adapt to the change of water level in the fluctuating zone reservoir.The indoor test of the new structure of gravity ecological retaining wall to avoid the adverse effects of water on plant growth is carried out.It is verified that the retaining wall structure can realize the protection of plants under the condition of high water level,and the rationality of structural function design is proved(3)The FLAC3 D finite difference software was used to carry out the numerical simulation research on the stress and strain of the new gravity ecological retaining wall structure.The results show that the stress on the water surface of the retaining wall is mainly compressive stress.The stress concentration occurs at the opening of the retaining wall.When the reservoir water level is 175 m,the stress at the opening of the wall is the largest,with the maximum tensile stress of 0.15 MPa and the maximum compressive stress of 0.067 MPa.They are not exceeding the allowable values of the tensile strength and compressive strength of the retaining wall structure.According to the above numerical analysis results,Fish language is compiled to extract the earth pressures of the walls under 145 m 、155m、165m and 175 m water levels.The extracted earth pressures are used for the stability calculation of the retaining wall.The calculation results show that the minimum anti-sliding stability coefficient of the retaining wall is 2.29,the minimum anti-overturning stability coefficient is 4.01,the maximum shear stress of the wall is 47.85 k Pa,and the maximum compressive stress is 101.55 k Pa,which all meet the requirements of the specification.Based on the above analysis,the stress and deformation,anti-skid and anti-overturn of the new gravity ecological retaining wall meet the requirements,and the structure design is reasonable.