ROCK SLOPE FAILURE BLOCKS an‎d THEIR RELATION TO TECTONIC ACTIVITY: A CASE STUDY IN 3B HIGHWAY, XUATHOA AREA, BACKAN PROVINCE, VIETNAM

This paper presents the results of the slope failure analyses from fracture distributions and their relation to tectonic activity; the analytical results have indicated that the phenomena of plane failure, wedge failure and toppling failure can occur at almost of the survey sites within the study area.The statistical data show that the fracture orientation mainly develop in the E-W, N-S and NW-SE due to the influence of tectonic activity. The occurrence of them together with the rock slope surfaceorientation has formed plane failure on the slope surface of the 3B highway in the E-W direction and the types of wedge failure and toppling failure on the slope surface of the highway in the N-S and NW-SE direction.