Discussion Of Nonlinear Distribution Of Seismic Earth Pressure On Retaining Wall Under Non-single Plane Sliding Failure Mode

Retaining wall is an earthen structure to prevent the collapse of side slope. It is widely used in hydraulic engineering, port engineering, building engineer ing, highway engineering and railway engineering, etc. With the rapid development of China economy, the pace of infrastructure construction throughout the country continues to move forward. However, the existing transportation construction in the central and western regions can not meet the needs of their economic development. This situation put forward new challenges to retaining wall engineering of infrastructure construction. The seismic earth pressure calculation plays a critical role in the earthquake resistant design of retaining wall. Western scholars have been working on the study of earth pressure since the 17 th century. However, the research on seismic earth pressure of retaining wall move slowly, which still focus on the theoretical construction. Therefore, there exist lots of defects and deficiencies in the related engineering practice. But in recent decades, many experts and scholars at home and abroad made a lot of efforts on theoretical research and engineering application,and they have put forward many theories and methods to solve that problem. All of them can provide effective evidence for the seismic design and construction of the retaining wall. However, due to the severe destruction of the earthquake and many uncertain factors, the resear ch on seismic earth pressure of retaining wall is still a hot topic in academic and engineering fields.At present, the ‘M-O' seismic earth pressure theory is the most widely used. This theory assumes that the failure surface is a plane when calculating th e seismic earth pressure, but in reality, they are basically irregular and curved. The differences between them are quite significant. Further more, there are also many other short comings. For example, it can't be applied to clay. It does not take the amplification effect of the earthquake and linear distribution of the seismic earth pressure into consideration.Because the quality of retaining wall construction is affected by the weather, terrain and construction period, the landfill of the back wall can not be totally homogenous. This paper assumes that retaining wall back is filled with two layers of cohesionless and dry soil with different properties, and the sliding failure surface under earthquake is non-single plane. Based on the level-layer analysis approach, we set up different equations of seismic earth pressure under the circumstance of earthquake.The nonlinear distribution of analytic solution under earthquake is obtained by solving model. We analyzed the seismic coefficient effect, and the eff ect of internal friction angle on the distribution of seismic earth pressure, the resultant earth pressure and the point of application. The results show that earth pressure on retaining wall of the upper soil is basically the same as that under planar fa ilure mode, and is characterized by the non-linear change. However, earth pressure on retaining wall of the lower landfill tend to have a linear relationship with the change of depth. Thus, earth pressure of the upper filled soil is a key part of the analy ses. This research effectively improved the calculation precision of the seismic earth pressure under complex conditions. It is also expected to have a guiding significance for the design, construction and cost control in the future.