摘要: |
为了研究黄河口海床沉积物固结过程中电阻率同工程力学性质指标的对应关系, 探索海床土体固结过程的新型原位监测技术, 本文在黄河刁口流路三角洲叶瓣潮坪上, 现场取土配置黄河口快速沉积形成的流体状沉积物和观测研究粉质土海床的固结过程。利用静力触探、十字板剪切试验、孔隙水压力监测等原位土工测试手段, 实时测定固结过程中海床土强度变化和孔隙水压力消散过程; 同时通过埋置自行研制的环形电极探杆, 实时测定海床土固结过程中的电阻率变化。通过对比分析海床土电阻率与工程力学性质指标的同步测定数据发现: 黄河口饱和粉土的电阻率与微型贯入试验测得的土体贯入强度, 静力触探试验测得的比贯入阻力, 十字板剪切试验测得的不排水抗剪强度(峰值强度、残余强度)均呈乘幂关系, 且相关性良好; 海床沉积物在固结过程中的电阻率与孔隙水压力呈负线性相关性。 |
关键词: 黄河口, 沉积物, 原位监测, 固结, 电阻率 |
DOI:10.11693/hyhz201202004004 |
分类号: |
基金项目:国家863计划资助项目, 2008AA09Z109号; 国家自然科学基金项目, 40876042、41072215号 |
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IN-SITU MONITORING OF SEABED SEDIMENTS CONSOLIDATION PROCESS IN YELLOW RIVER ESTUARY BY ELECTRICAL RESISTIVITY METHOD |
LIU Xiao-Lei1, SHAN Hong-Xian2,1, JIA Yong-Gang2,1, LI Hong-Lei1, ZHENG Jie-Wen1
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1.College of Environmental Science & Engineering, Ocean University of China;2.Key Laboratory of Marine Environment & Ecology, Ministry of Education
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Abstract: |
In order to study the correlations between resistivity and mechanical properties of the seabed sediments during the consolidation process in the Yellow River estuary, and to explore a new in-situ monitoring technique for the process, a series of experiments were conducted on the tidal flat of Diaokou delta-lobe that lies in the north of the Yellow River Delta. The fluid sediments imitating the rapidly depositing seabed silts were taken in situ, and the fluid sediments were promptly filled into a one-meter deep pit excavated on the tidal flat. Using field-testing methods, including static cone penetration test, field vaneshear test and pore water piezometer test, variations in mechanical strength and dissipation of pore water pressure were measured in real time. A homemade monitoring probe with ring electrodes was alsoburied in the sediments to measure the real-time resistiv-ity during the sediment consolidation process. Based on the experimental data, good power correlations were found between re-sistivity and penetration strength, specific penetration resistance and undrained shear strength (includingpeak strength and re-sidual shear strength) of the saturated silty soil in the Yellow River ESTUARINE area. There was a negative linear correlation between resistivity and pore water pressure. We propose that resistivity method can be used as an effective way to obtain the degree of consolidation of the silty soil in the Yellow River estuarine area. |
Key words: Yellow River estuary, Sediment, In-situ monitoring, Consolidation, Resistivity |