Study On Dynamic Characteristics And Seismic Response Of Reinforced Retaining Wall

Reinforced retaining wall has the advantages of simple construction and low cost,and has been widely used in retaining structures of highway,railway and other civil engineering in recent years.Compared with gravity retaining wall,reinforced retaining wall has good seismic performance under the action of low intensity earthquake.However,the seismic performance of reinforced retaining wall under the action of high intensity earthquake has not been clearly studied,which limits its popularization and application in high intensity area.In order to further popularize the application of reinforced retaining wall in earthquake zone,it is necessary to conduct a comprehensive study on the structural dynamic characteristics and seismic response of reinforced earth retaining wall.In this paper,the dynamic characteristics of reinforced earth retaining wall are analyzed and summarized to provide reference suggestions for seismic design.The specific contents are as follows:(1)Natural frequency is an important parameter reflecting the structural dynamic characteristics,is the primary content of structure dynamic study,through summary analysis of the existing structure natural frequency calculation method,established the Pasternak double parameters foundation and Bernoulli Euler beam reinforced retaining wall of interaction between natural frequency calculation model,grey correlation analysis method is introduced to the filled soil elastic modulus,poisson’s ratio,heavy,cohesion,internal friction Angle of the influencing factors,and analyzes the correlation between influencing factors and inherent frequency,the sensitive factor get reinforced retaining wall vibration characteristics.By comparing the natural frequencies of reinforced retaining wall and gravity retaining wall,the seismic performance of reinforced retaining wall panel and gravity retaining wall is compared.(2)Displacement seismic design of reinforced retaining wall is an important aspect,and the damage degree after earthquake depends largely on its deformation during earthquake.Admissible displacement based seismic design is the development trend of seismic design of structures.In order to study the seismic displacement of the reinforced retaining wall,a displacement calculation equation was established based on the linear simplified fracture surface,and the seismic displacement of the reinforced retaining wall was calculated by using the principle of limit analysis,and the influencing factors of the displacement were analyzed.The calculation results show that the displacement of reinforced retaining wall and gravity retaining wall is similar under the weak earthquake condition,but with the increase of earthquake acceleration,the displacement of gravity retaining wall increases faster,and the displacement of reinforced retaining wall increases slower.(3)This paper proposes a new method to calculate stability of reinforced retaining wall earthquake,the reinforced retaining wall fracture surface as composed of multiple inclined line more linear fracture surface form,the line in a plane with different lengths and angles are interconnected to the reinforcement material always tension value as the objective function,by solving the objective function of random search procedure to determine the tensile strength of the reinforcement materials and the failure surface location.The influencing factors of the internal stability of the reinforced retaining wall were analyzed by using this method,and the influence laws of the sliding fracture surface,the tensile force and the length of the reinforcement on the stability of the reinforced retaining wall were summarized,in order to provide a reference for the seismic design of the stability.(4)Time history analysis is an effective method to study the vibration process characteristics of reinforced retaining wall.Considering the complexity of the constitutive relation of geotechnical materials,and the reinforcement and soil composite material is equivalent to a structural form considering the sliding between the reinforcement and soil,the finite element dynamic time history calculation program of composite response is developed.The vibration time history of gravity retaining wall and reinforced retaining wall is calculated,the dynamic response of the two different types of retaining wall is compared and analyzed,and the dynamic performance of reinforced earth retaining wall is summarized.(5)According to the calculation and analysis,comprehensive seismic mechanism of reinforced retaining wall structure are summarized and proposed the corresponding seismic design suggestions,through the analysis of the factors affecting the seismic behavior of reinforced retaining wall,advances some measures for improving the seismic performance of reinforced retaining wall structure,for the earthquake reinforced retaining wall panel micro cracks of concrete can be used in high pressure injecting method is put forward to repair.