THE FORMATION OF SHEAR BAND AND THE BEHAVIOR OF REINFORCED SOIL SLOPES

The failure mechanism in slopes usually start with the formation of a shear band or inother words, the formation of a failure zone with higher shear stresses that eventuallyleads to the formation of a failure surface. The shear band shape is dependent uponthe soil type or specifically the shear strength parameters, and it is not necessarilycircular as most analysis tools assume. To prevent slope failures and allow forsteeper and higher slopes of compacted soils, layers of reinforcements are arrangedin soil slopes for stabilization to control the shear band and consequently shearfailure. The special purpose geotechnical software Plaxis is used in the numericalanalysis of slopes to identify the shear band for different soil types and to study thebehavior of reinforced soil slopes. The studied parameters included, number of soilreinforcement layers, layer position, geogrid length, and slope angle are all presentedin an optimized form. Results showed that for cohesive soils, the shear band is deepand can be clearly identified. On the other hand, for cohesionless soils, the shearband is shallow and took a block-like failure shape. Results also showed that thelocation of the reinforcement layers is more effective than the number of layers.Lower layers are subjected to higher tension forces and upper layers resist lowerloads.