Study on the Failure Surface of Heterogeneous Soil at the Passive State
Study on the Failure Surface of Heterogeneous Soil at the Passive State Fei Song*, Rui-Zhi Cheng, Li-Qiu Ma, Xi-Bin Tang, Wen-Zhong Yuan Institute of Geotechnical Engineering, School of Highway Engineering, Chang’An University, Xi’an, 710064, P.R. China Guizhou Electricity Engineering Construction Supervise Company, Guiyang, 550005, P.R. China Guizhou Electric Power Design Institute and Research Institute, Guiyang, 550002, P.R. China songf1980@163.com
Static and dynamic active earth pressure
SummaryThe dynamic active earth pressure on retaining structures due to seismic loading is commonly obtained by using the modified Coulomb's approach which is known as the Mononobe-Okabe method. This method has generally been used for cohesionless soils only. A general solution for the determination of total (i.e. static and dynamic) active earth force for a c-ϕ soil as backfill was developed by Prakash and Saran in 1966 based on the simplifying assumption that adhesion between the wall-soil interface is equal to the cohesion of the soil, that the surface of the backfill is horizontal, and that the effect of the vertical acceleration can be neglected. This note presents an improved method for calculating the static and dynamic active force behind a rigid retaining wall based on its geometry, inclination of the backfill, surcharge, strength parameters of the backfill, and the adhesion between the wall face and the soil. The effects of adhesion, inclination of backfill, and vertical components of seismic loading for a typical retaining wall are discussed.
MODEL STUDY OF PASSIVE PRESSURE IN SAND
RESULTS ARE PRESENTED OF A STUDY PRESSURE MODEL WITH GLASS SIDES TO DETERMINE THE RUPTURE SURFACES AND THE DISTRIBUTION OF PRESSURES ON A RIGID RETAINING WALL. EMPHASIS IS LAID ON THE EFFECT OF ROTATION OF THE WALL ON THE MAGNITUDE AND DISTRIBUTION OF PRESSURE AND SHAPE AND SIZE OF THE RUPTURE WEDGE. IT IS CONCLUDED THAT THE TYPE OF WALL DISPLACEMENT IS ONE OF THE IMPORTANT FACTORS AFFECTING THE PRESSURES AND THE RUPTURE WEDGE. FURTHER, IT IS POINTED OUT THAT THE COMMON EARTH PRESSURE THEORIES ARE INADEQUATE TO ASSESS PASSIVE PRESSURES CORRECTLY. /ASCE/