二维动床数学模型在某地铁隧道冲刷深度研究中的应用

河床冲淤是河床在垂直方向上演变的一种形式,它对于河道行洪排涝、涉水工程安全、航道运行乃至自然景观都会产生一定的影响,研究河道冲淤变化具有重要现实和理论意义。本文以宁波市地铁2号线下穿姚江工程为例,应用二维潮流泥沙数学模型与经验公式计算相结合的方法,对在遭遇不同洪潮组合条件下地铁线位处河床的最大冲刷深度进行了研究,为地铁工程的设计提供重要参考依据。研究结果表明,洪水频率越小,工程线位附近河段的最大冲刷深度愈大,冲刷发展呈先加快后减慢的态势。

Application of the two-dimensional movable-bed mathematical model to the study of erosion depth in a subway tunnel

Scour and siltation are the forms of riverbed evolution in the vertical direction, which have some impacts on river flood control and drainage, safety of wading engineering, shipping and natural landscape. So it is important practical and theoretical significance to research the riverbed evolution. Taking the engineering of Ningbo Subway Line 2 undercrossing the Yaojiang River as an example, the method of 2-D mathematical model of tidal flow and sediment combined with the method of empirical formula calculation were used to research the greatest scour depth of riverbed near subway line under different flood and tide conditions. The research results show that the flood frequency become smaller, the maximum scour depth of riverbed near the engineering line become deeper, and riverbed scour develops quickly at first, and then slow down gradually.