砂石铺砌对桥墩冲刷影响分析

Analysis on Impact of Sand and Gravel Paving on Bridge Pier Scour

摘要:

为探究砂石铺砌防护措施对桥墩河床冲刷的抑制效果，依托实际工程设计文件，采用水文分析获取实际参数，结合FLOW3D数值仿真技术，对比分析砂石铺砌前后桥墩周围流场特征及冲刷深度变化。结果表明：砂石铺砌后，河底粗糙度显著增加，桥墩迎水侧流速降低约15%，最大冲刷深度由2.4 m缩减至1.3 m。砂石级配（平均粒径3 mm，粒径占比90%）与铺砌厚度（2 m）的协同作用有效遏制了河床下切。研究成果为桥梁防冲刷设计提供了量化依据。

Abstract:

To explore the inhibitory effect of sand and gravel paving protection measures on riverbed scour around bridge piers，relying on the design documents of practical projects，the hydrological analysis is used to obtain the actual parameters. Combined with FLOW3D numerical simulation technology，the flow field characteristics and scouring depth changes around the bridge piers before and after sand and gravel paving are compared and analyzed. The results show that after sand and gravel paving，the roughness of the riverbed significantly increases，the flow velocity on the water-facing side of the bridge pier decreases by about 15%，and the maximum scouring depth is reduced from 2.4 m to 1.3 m. The synergistic effect of the sand and gravel gradation (with an average particle size of 3 mm accounting for 90%) and the paving thickness (2 m) effectively restrains the riverbed incision. The research findings provide a quantitative basis for the anti-scouring design of bridges.