港珠澳大桥青州航道桥桥墩基础冲刷试验研究

桥墩基础冲刷是桥梁毁坏的重要因素，是桥梁基础设计的关键指标之一。目前国内外对于桥墩基础在复杂动力条件下冲刷深度的研究常采用物理模型试验方法，利用正态系列模型方法，在波流水槽中研究了水流、潮流和波流共同作用下青州航道桥索塔基础周围流态变化和局部冲刷特征。研究结果表明，桥墩最大冲刷深度和冲淤范围与水流流速、桥墩轴线与水流夹角和波浪等因素有关；在潮流最大流速和恒定流流速一致情况下，桥墩局部冲刷深度达到平衡后，将会达到与恒定流基本一致的最大冲深；波流共同作用下的最大冲刷深度比恒定流增加10%左右。设计桥墩形状在100年一遇水流和波浪共同作用下桥墩基础局部最大冲刷深度为13.7 m。

Experimental study on scouring of pier foundation of Qingzhou channel bridge

Scour of pier foundation is one of the important factors in bridge damage and the key indexes of bridge foundation design. At present, physical model test is often used to study local scour of bridge pier under complex dynamic conditions. In this research, the normal series model method is used to study the flow regime change and local scour characteristics around the cable tower foundation of Qingzhou channel bridge under current, tidal current and the interaction of wave and current in a wave-current flume. The results show that the maximum scour depth and scour range are related to the flow velocity, the flow and pier angle and the wave; under the condition that the maximum current velocity is consistent with the constant current velocity, the maximum scour depth of the pier is basically consistent with that of the constant current after the local scouring is balanced; the maximum scour depth under the combined action of wave and current is about 10% higher than that of the constant current. The maximum local scour depth of the pier foundation is 13.7 m under the combined action of once-in-one-hundred-year water flow and waves.