桥墩阻水比对弯道河流流速分布的影响

桥墩阻水比是确定涉河桥梁工程方案主要考量指标之一。为研究桥墩阻水比对弯道河流流速分布的影响，建立有机玻璃弯道水槽模型，针对不同阻水比桥墩对弯道河流流速分布影响开展试验研究。使用ADV采集弯道试验段内的纵向和横向流速并进行分析，结果表明：随阻水比的增大，桥墩附近上下游主流位置趋于集中在水槽中间。在Fr=0.21和Fr=0.28两组工况下，墩前断面纵向流速方差均减小，其流速分布更加均匀；墩后断面纵向流速方差均增大，其流速分布更加紊乱；横向流速在墩前与墩后分布均更加紊乱。桥墩阻水比对纵向流速和横向流速分布的影响均随Fr增大而减小。

Influence of Piers Water Resistance Ratio on Velocity Distribution in Curved River

The piers water resistance ratio is one of the main consideration indexes for determining the engineering scheme of river related bridge. In order to study the influence of piers water resistance ratio on velocity distribution in curved river, a plexiglass curved flume model was established. An experimental study was carried out to study the influence of piers with different water resistance ratio on the velocity distribution in curved river. The collection and analysis of longitudinal and transverse velocity in the curved test section by ADV. The results show that with the increase of water resistance ratio, the upstream and downstream mainstream positions near piers tends to be concentrated in the middle of the flume. Under the conditions of Fr=0.21 and Fr=0.28, the variance of longitudinal velocity in front of piers decreased, and the velocity distribution becomes more uniform. The variance of the longitudinal velocity behind piers increases, and the velocity distribution becomes more disordered. The distribution of transverse velocity in front of piers and behind pier is more disordered. The influence of piers water resistance ratio on longitudinal and transverse velocity distribution decreases with the increase of Fr.