Abstract: Stability of a cutting slope at various stages, including those before and after the pile group construction, during the bridge construction, and under the train operation, were simulated using a strength reduction method, the Mohr-Coulomb failure criterion, and the finite element analysis technique. The existing specifications were used to simulate the live load and braking force of the pier top under the train operation. A three-dimensional finite element model was then established according to the practical locations of the geomaterials in the cutting slope. The influences of the loads on stability of the slope in bridge construction and operations were investigated. The study shows that the stability factors of the slope were 1.35 and 1.63 before and after the pile group constructions, respectively. The stability factors were 1.61, 1.60, 1.58, and 1.57 as the height of pier were 6.0, 12.0, 18.0, 22.5 m, respectively. In completion of the bridge construction and under the train operation, the safety factors decreased to 1.55 and 1.53, respectively. During the entire construction, the safety factors were decreased obviously. Nevertheless, the Mises stresses in the plastic zone increased as these safety factors decreased. The results presented herein may be used as references in the design and construction of bridges in a rock slope under various surrounding conditions.

Key words: bridge construction and operation, rock slope, stability, strength reduction method