Abstract:Through a series of pullout tests under different vertical stresses,a study was made of the mesoscopical behavior of the interface between two-way geogrid transverse rib and sand based on digital visual tracking technology and no punctuation soil deformation measurement techniques.The interface being traced with the techniques of no punctuation soil deformation measurement,a quantitative analysis was made of the changes of interface movement.Analysis results show that the apparent friction coefficient is related with the vertical stress.Mesoscopical results show the upper interface thickness of transverse rib and sand is different from the lower.In whole,the upper thickness is greater than the lower,and the rib on the interface motion is more intense.The mesoscopical displacement strain plot shows the rib damage model of this research is similar to the piercing damage model proposed by Jewell,but the upper part is slightly larger than the lower of the regional area.Jewell piercing damage model is basically authenticated.