التقييم الجيولوجي الهندسي لاستقرارية منحدرات المدملكات في منطقة سامراء( وسط العراق)

Abstract

Engineering geological study for conglomerate slope stability in Tigris river bank was carried out, at 4 selected stations lying along the cliffs adjacent to the houses , west of Samarra city (Middle of Iraq). At each station rock slopes and the discontinuities were comprehensively surveyed and the relationships with failures were determined. The conglomerate rocks were described in engineering terms, the types of failures recorded during field study were (from the most to the least abundant) : rock fall , toppling , rolling and sliding . The study also revealed that factors affecting slope stability in the study area were slope angle and height, differential weathering and erosion, the discontinuities. (which are almost normal to the bedding planes), water used in the nearby houses on the slope's crests and springs at slope's toe which lead to weaken the rock masses and help their failure .The laboratory tests of the rock samples have shown (point -load test ) that values of compressive strength of the rock for the study area range between (c =5- 74.1 MPa), some remedial measures are proposed for the unstable slopes.