双桥墩条件下冰塞发展临界条件试验初步研究

河流中的桥墩改变了附近原有的水流特征，冬季可能对其附近冰塞的形成和演变产生影响。基于水槽模型试验，通过改变墩心距、墩径、墩形、冰水流量比和水流弗劳德数，分析了双桥墩条件下冰塞发展通过桥墩的临界条件。试验表明：冰塞能否发展通过桥墩所在断面存在临界弗劳德数，其值受墩心距、墩径、墩形和冰水流量比等因素控制，随着墩心距的减小或冰水流量比、墩径的增大，冰塞发展通过桥墩所在断面难度增大，方形墩相较于圆柱形墩难度增大；试验范围内，随着墩心距的减小，桥墩所处河道断面输冰能力增强，初始冰塞厚度增加，但冰塞平衡厚度减小。

Experimental study on critical conditions for ice jam development around side-by-side piers

The bridge piers in the river change the original flow characteristics nearby,which may affect the formation and evolution of ice jam near the piers in winter.Based on the flume model test,the critical conditions of ice jam development through double piers were analyzed by changing the pier center distance,pier diameter,pier type,ice water flow ratio and flow Froude number.The test shows that there is a critical Froude number in the section where the ice jam can develop through the pier,and its value is controlled by the factors such as pier center distance,pier diameter,pier type and ice water flow ratio.With the decrease of pier center distance or the increase of ice water flow ratio and pier diameter,it becomes more difficult for the ice jam to develop through the pier section,and the difficulty of square pier is higher than that of cylindrical pier.Within the test range,with the decrease of pier center distance,the ice transport capacity of the river section at the pier is enhanced,and the initial ice jam thickness increases,but the ice jam equilibrium thickness decreases.