The effects of a cracked tunnel underneath a canal bed on water and sand inflow through the tunnel hole and distortion of the canal bed were experimentally examined. A circular hole in the centre of the base plate of the flume was used to simulate the cracked tunnel. In total, 108 tests were conducted to investigate four factors that affect canal bed morphology (four water depths, three bed material sizes, four hole diameters and three bed material heights above the tunnel hole). The water and sand discharges into the tunnel hole were measured. The scour bed geometry due to the cracked tunnel, including the erosion volume and scour hole dimensions, was also measured and analysed. The results indicated that the sand height, tunnel hole diameter and bed material particle size were the important factors affecting the sand flux, while Froude number and canal water depth were the parameters governing the water flow rate. The tunnel hole became blocked when the particle size was larger than 0·2 times the tunnel hole diameter, indicating that this could be used to temporarily block a cracked tunnel. Relationships were developed to correlate the investigated parameters and to estimate the flow rate and the volumes of water and sand passing through the tunnel hole.

中文翻译：

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沙子和水流入水底隧道洞的实验室研究

通过实验检查了在河床下面开裂的隧道对通过隧道孔的水和沙流入以及河床变形的影响。水槽底板中央的圆形孔用于模拟开裂的隧道。总共进行了108次测试，以研究影响运河床形态的四个因素（四个水深，三个床料尺寸，四个孔直径和三个隧道床上方的三个床料高度）。测量了进入隧道孔的水和沙。还测量和分析了由于破裂的隧道造成的冲刷床几何形状，包括侵蚀量和冲刷孔尺寸。结果表明，砂的高度，隧道孔直径和床料粒径是影响砂通量的重要因素，弗洛德数和运河水深是控制水流量的参数。当粒径大于隧道孔直径的0·2倍时，隧道孔被堵塞，表明这可以用于暂时堵塞破裂的隧道。建立关系以关联所研究的参数，并估计流量以及通过隧道孔的水和沙的体积。