"Local scour analysis around a group of pillars with diverse geometries applying 2D modeling - Piura - Peru"

This article analyzes the results of the local scour calculations around the group of pillars of a bridge through two-dimensional modeling using the Iber software. The case under study is that of the Andrés Avelino Cáceres Bridge, located in the Piura region, Peru, which has an approximate free span of 120 meters and has 10 pillars equally distributed on two decks. Currently, the referred bridge has pillars of rectangular section with narrowing towards the base. This type of geometry was considered as the first scenario for local scour calculations, considering in the comparison three more additional cases: pillar with rectangular section without narrowing (scenario 2), pillar with sharp point (scenario 3) and pillar with circular tip (scenario 4). These geometries are considered in the Froehlich method and the Colorado State University (CSU) method. Based on geotechnical, hydrological and hydraulic studies of the area, numerical modeling has been developed for each scenario in order to obtain the depths of local scour. The following results were obtained: the geometry proposed in the second scenario achieved a reduction of the local scour depth by 64%; on the other hand, the geometries corresponding to scenarios 3 (sharp point section) and 4 (round point section), present maximum erosive depths in the bed of up to 2.02 m and 2.25 m, respectively, it is for this reason that these types are recommended. of pillars for the lateral regions of the channel under study, where the sedimentation process occurs.