Research On The Performance Of Reinforced Retaining Wall Under Equilibrium Humidity

Reinforced retaining walls have the advantages of low cost,small footprint,and strong resistance to deformation,and are widely used in practical projects.After investigation,the damage of the reinforced retaining wall is affected by rainfall and the rise and fall of the groundwater level.To solve this problem,this paper uses a combination of indoor experiments and numerical simulation to control the internal balance of the reinforced retaining wall under the influence of rainfall and groundwater level.The humidity distribution law and performance change trend were studied.The main research contents and conclusions are as follows:(1)The influence of matrix suction on the interface characteristics of reinforcement and soil.The filter paper method was used to measure the matrix suction corresponding to the soil samples with different volumetric water contents,and draw the soil-water characteristic curve.The direct shear test is used to study the influence of matrix suction on the strength parameters of the interface between reinforcement and soil.The test results show that: 1)When the volumetric water content is less than 15%,the matrix suction has a greater contribution to the overall stability of the reinforced soil project.2)As the suction of the matrix increases,the shear strength of the interface between the reinforcement and soil increases.With the increase of the vertical stress,the shear strength of the interface between the reinforcement and soil also gradually increases,and the increase is most obvious when the vertical stress is 300 k Pa.3)The internal friction angle and the cohesive force,which are the strength parameters of the interface between the reinforcement and the soil,increase approximately linearly with the increase of the matrix suction.(2)The distribution law of the moisture field inside the reinforced retaining wall.The water infiltration model of reinforced retaining walls under different groundwater levels,different rain intensities and different rainfall durations was established,and the water distribution law inside reinforced retaining walls was studied.The analysis shows that: 1)When the buried depth of the local water level is greater than 10 m,the difference between the water content of the top of the wall and the bottom of the wall is extremely small.At this time,the internal humidity of the reinforced retaining wall can be regarded as a constant value.2)The shallow fill within 1m from the top of the retaining wall is greatly affected by the duration of rainfall.In the design and construction of the reinforced retaining wall,the hazard of rainfall should be considered for the shallow fill.3)With the increase of rainfall intensity,the wider the depth range affected by rainfall infiltration,the water content of the soil at different heights in the reinforced retaining wall will increase.(3)Research on the internal equilibrium humidity of the reinforced retaining wall.Through comparative analysis,it is determined that the Fredlund&Xing model is used as the internal equilibrium humidity prediction model of the reinforced retaining wall.According to the test results of the filter paper method and the Matlab software,the parameters of the Fredlund&Xing model are calibrated.A prediction method for the internal equilibrium humidity of the reinforced retaining wall is proposed,and a matrix suction prediction model for the climate control area is established.A comparative analysis of the estimated results and the numerical analysis results proves that the estimation method is reasonable and reliable.(4)Performance and stability analysis of reinforced retaining walls.The stress-strain model of the reinforced retaining wall under different groundwater levels and rainfall conditions is established,and the maximum lateral and axial deformations are analyzed.The failure mode and stability of the reinforced retaining wall under the equilibrium humidity state are studied.The analysis shows that: 1)When the groundwater level is higher than 8m,as the groundwater level decreases,the deformation restraint ability of the reinforced material on the reinforced retaining wall will be significantly improved.2)When the volumetric water content is less than 25%,the performance of the reinforced retaining wall is good,and its deformation amplitude is less affected by humidity.3)In the initial state and the equilibrium humidity state,the stability of the reinforced retaining wall is quite different.Using the safety factor under the equilibrium humidity state to evaluate the stability of the reinforced retaining wall is more in line with the actual situation.4)When using the safety factor under the initial humidity state to evaluate the stability of the reinforced retaining wall,the safety factor needs to be corrected,and the correction factor is 0.91.