The characteristics of consolidation settlement and its contribution to the topographical change in the northern modern Huanghe River subaqueous delta in China

• Published in: Acta oceanologica Sinica 2015-09, Vol.34 (9), p.136-142
• Main Authors: Liu, Jie, Li, Ping, Liu, Xiao, Xu, Yuanqin, Gao, Wei
• Format: Article
• Language: English
• Subjects: Boreholes; Climate change; Climatology; Compressibility; Consolidation; Deposition; Depth measurement; Drilling; Earth and Environmental Science; Earth Sciences; Ecology; Engineering Fluid Dynamics; Environmental Chemistry; Erosion rates; Flow velocity; Fluid mechanics; Hydrodynamics; Laboratories; Laboratory experimentation; Marine & Freshwater Sciences; Mathematical models; Moisture content; Numerical models; Ocean engineering; Oceanography; Offshore; Rivers; Sea level; Sediment; Sediments; Soil erosion; Stratigraphy; Topography; Void ratio; Water content; Water depth; 一维固结理论; 中国北方; 固结沉降; 地形变化; 实测数据; 水深测量; 钻孔数据; 黄河水下三角洲
• ISSN: 0253-505X; 1869-1099
• DOI: 10.1007/s13131-015-0732-6

The sediments of the modern Huanghe River subaqueous delta are easily to generate settlement and lead to topography change which is due to fast deposition rate, high void ratio, moisture content and compressibility. The sediment consolidation settlements and its contribution to the topography change in the northern modern Huanghe River subaqueous delta are studied based on drilling data, laboratory experiment results, and water depth measurements of different time. The results show that the final consolidation settlement of drill holes in the study area is between 1.17 and 3.21 m, and mean settlement of unit depth is between 2.30 and 5.30 cm/m based on the one-dimensional consolidation theory and Plaxis numerical model. The final consolidation settlement obtained by Plaxis numerical model is smaller than that obtained by the one-dimensional consolidation theory, and the difference is 3.4%-39.9% between the methods. The contribution of the consolidation settlement to the topographical change is at 20.2%-86.6%, and the study area can be divided into five different regions based on different contribution rates. In the erosion area, the actual erosion depth caused by hydrodynamics is lower than the changes of measured water depth, however, the actual deposition amount caused by hydrodynamics is much larger than the changes of water depth obtained by measured data in the equilibrium and deposition areas.