抛石防护桥墩冲刷水力计算

Hydraulic Computation for Riprap Protection against Scouring around Bridge Piers

根据散粒沙、石在水流作用中起动、输移和沉降规律,本文导出了抛石防护桥墩冲刷的石料尺寸和抛投距离的计算公式,并利用实验室资料和野外实测数据确定公式的指数和系数。通过15座桥梁汛期抛石防护桥墩效果检验,表明所提出的抛石水力计算公式计算精度可靠,可在实际工程中使用。

Based on the laws of initial movement, transport and falling of dispersed sand and stone particles on the riverbed under the action of water flows, the paper derives computation formulas for the size and throwing distance of ripraps used in pier protection against scouring, defines the factors and indexes in the formulas according to the test results and field observation data, and explains the close relationship between the riprap protection effect and water flow conditions, and riprap elevation and riprap quantity. The field investigations on riprap protection at 15 bridges show that the hydraulic computation, formulas proposed in the paper are practically effective and its application in practice can be promoted.