| 摘要: |
| 在研究伶仃洋水沙运动规律的基础上,依据港珠澳大桥沉管隧道试挖槽现场实测的17组水下地形资料,并结合γ-射线密度仪在试挖槽基槽及边坡进行的浮、淤泥重度探测结果,对试挖槽的泥沙回淤特征进行分析,获得了试挖槽回淤的速率变化及分布特征,明确了稳定边坡的坡比,区分出槽内浮泥层和淤泥层的厚度及其变化趋势.本文还分析了洪水和台风对挖槽回淤的不同影响,指出由枯转洪的首场洪水会明显增加淤积.另外,还对3种不同频率超声测深的对应数据进行了统计分析,发现多波束与低频测深仪所测数据之间存在0.30 m的水深差值,与现场实测的浮泥厚度基本吻合. |
| 关键词: 试挖槽 回淤观测 边坡 浮泥 |
| DOI： |
| 分类号:TV148 |
| 基金项目: |
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| Back silting analysis of the trial dredged-trough for immersed tube tunnel of Hong Kong-Zhuhai-Macao Bridge |
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XIN Wen-jie,JIA Yu-shao,HE Jie
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(State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Research Institute,Nanjing 210029,China)
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| Abstract: |
| On the basis of a study of water-sediment movement in the Lingdingyang sea area,back silting characteristics of the trial dredged-trough of the immersed tube tunnel of Hong Kong-Zhuhai-Macao Bridge(HZMB) are analyzed,with 17 groups of underwater topographic survey data and the measured results of fluid mud and silt unit weight in the base trough and slopes.And some results are obtained,including the siltation rate changes and sediment distribution characteristics of the trial dredged-trough,the slope ratio of steady slope,the thickness and change trends of the fluid mud layer and silt layer in the trough.This paper analyzes the different impacts of flood and typhoon on back silting,and points out that the first flood from dry season to flood season will increase siltation remarkably.Besides,based on the statistics of ultrasonic depth-sounding with three different frequencies,it is found that there is a difference of 0.3 m between multi-beam and low frequency,which coincides with the measured values of the fluid mud thickness of 0.29 m very well. |
| Key words: trial dredged-trough back silting observation slope fluid mud |
