Retrieved from Iss. 117, P. 2, 2025
Pages 285 -296
Received 17.02.2025
Revised 24.05.2025
Accepted 24.06.2025
Retrieved from Iss. 117, P. 2, 2025
Pages 285 -296
Abstract
The purpose of the work is to determine the features of scour during the group arrangement of bridge piers using laboratory experimental researches. Materials and methods. Experimental researches of the features of scour formation during the group arrangement of piers of two bridge crossings, which were in the wake of each other, were carried out on models of piers in laboratory conditions in a hydrodynamic channel using visual and instrumental research methods. Hydrodynamic characteristics of vortex and jet flows were obtained using specially designed and manufactured velocity and pressure sensors, and the parameters and shape of scour holes were determined using scour depth sensors. Results. Experimental researches allowed to determine the features of scour formation around the group structure of bridge piers. Profiles of local scour in front of the frontal part of the prismatic pier were obtained depending on the junction flow velocity, flow depth and Froude numbers for the single arrangement of the piers of the upper streamlined bridge crossing and the joint arrangement of the piers of two bridge crossings. The features of the formation of scour and alluvium near bridge crossing piers in an axonometric representation are presented. Conclusions. As a result of the research, it was established that the mutual arrangement of the models of the piers of two bridge crossings leads to significant changes in the scour in front of the prismatic piers of the first streamlined bridge crossing. Thus, the local scour increased by 15% at supercritical flow velocities in shallow water and decreased by almost 20% at subcritical velocities in deep water. It is shown that the scour profiles have two characteristic sections with different angles of inclination of the front surface of the scour hole, which are due to the formation of two systems of quasi-stable large-scale horseshoe vortex structures
Keywords:
local scour, prismatic pier, three-row grillage, horseshoe vortex, scour profile, bridge crossing