Analysis of the OCR of soft clay in coastal areas based on field vane strength
GAO Yanbin1，CHEN Zhongqing2
(1. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China；2. School of Civil Engineering，Shaoxing University，Shaoxing，Zhejiang 312000，China)
Abstract：The over consolidation ratio(OCR) is an important parameter to evaluate deformation and strength characteristics of soil. The consolidation states and formation mechanism of the soft clay were analyzed based on the field vane strength of soft clay at six coastal areas in Tianjin，Shanghai，Lianyungang，Shenzhen，Zhongshan and Zhuhai. It was found that the OCR obtained from the field vane tests(FVT) was much larger than that obtained from the one-dimensional compression tests in laboratory and that the laboratory tests significantly underestimated the OCR of these soft clays. The variations of OCR with depth for these six areas are very similar and the OCR decreases to a stable value at a certain depth. The shallow soil shows over consolidation，but the deep soil shows some complexity. It was also found that Hanzawa and Tanaka?s model can explain the formation mechanism of over consolidation and the variation of OCR with depth. The over consolidation of shallow soils originates mainly from the complex“surface effect” of cement or weathering，while the over consolidation of deep soil is due to the secondary compression. Considering the considerable sampling disturbance，this method based on FVT for evaluating OCR is worthy of recommendation for Chinese coastal areas.
高彦斌1，陈忠清2. 基于原位十字板强度的沿海地区软黏土超固结比分析[J]. 岩石力学与工程学报, 2017, 36(10): 2572-2579.
GAO Yanbin1，CHEN Zhongqing2. Analysis of the OCR of soft clay in coastal areas based on field vane strength. , 2017, 36(10): 2572-2579.
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2017, Vol. 36 
