Experimental Research on Creep Characteristics of Nansha Soft Soil

A series of tests were performed to investigate the creep characteristics of soil in interactive marine and terrestrial deposit of Pearl River Delta. The secondary consolidation test results show that the influence of consolidation pressure on coefficient of secondary consolidation is conditional, which is decided by the consolidation state. The ratio of coefficient of secondary consolidation and coefficient of compressibilityCa/Ccis almost a constant, and the value is 0.03. In the shear-box test, the direct sheer creep failure of soil is mainly controlled by shear stress rather than the accumulation of shear strain. The triaxial creep features are closely associated with the drainage conditions, and consolidation can weaken the effect of creep. When the soft soil has triaxial creep damage, the strain rate will increase sharply.

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Surface deformation evolution in the Pearl River Delta between 2006 and 2011 derived from the ALOS1/PALSAR images

Earth Planets and Space ◽

10.1186/s40623-020-01310-2 ◽

2020 ◽

Vol 72 (1) ◽

Author(s):

Genger Li ◽

Guangcai Feng ◽

Zhiqiang Xiong ◽

Qi Liu ◽

Rongan Xie ◽

...

Keyword(s):

Land Subsidence ◽

Pearl River Delta ◽

Surface Deformation ◽

Soft Soil ◽

Soil Layer ◽

Intrinsic Factor ◽

Surface Subsidence ◽

River Delta ◽

Pearl River ◽

Human Interference

AbstractThis study monitors the land subsidence of the whole Pearl River Delta (PRD) (area: ~ 40,000 km2) in China using the ALOS1/PALSAR data (2006–2011) through the SBAS-InSAR method. We also analyze the relationship between the subsidence and the coastline change, river distribution, geological structure as well as the local terrain. The results show that (1) the land subsidence with the average velocity of 50 mm/year occurred in the low elevation area in the front part of the delta and the coastal area, and the area of the regions subsiding faster than 30 mm/year between 2006 and 2011 is larger than 122 km2; (2) the subsidence order and area estimated in this study are both much larger than that measured in previous studies; (3) the areas along rivers suffered from surface subsidence, due to the thick soft soil layer and frequent human interference; (4) the geological evolution is the intrinsic factor of the surface subsidence in the PRD, but human interference (reclamation, ground water extraction and urban construction) extends the subsiding area and increases the subsiding rate.

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Surface Deformation Evolution in the Pearl River Delta between 2006 and 2011 derived from the ALOS1/PALSAR images

10.21203/rs.3.rs-32256/v2 ◽

2020 ◽

Author(s):

Genger Li ◽

Guangcai Feng ◽

Zhiqiang Xiong ◽

Qi Liu ◽

Rongan Xie ◽

...

Keyword(s):

Land Subsidence ◽

Pearl River Delta ◽

Surface Deformation ◽

Soft Soil ◽

Soil Layer ◽

Intrinsic Factor ◽

Surface Subsidence ◽

River Delta ◽

Pearl River ◽

Human Interference

Abstract This study monitors the land subsidence of the whole Pearl River Delta (PRD) (area: ~40,000 km2) in China using the ALOS1/PALSAR data (2006-2011) through the SBAS-InSAR method. We also analyze the relationship between the subsidence and the coastline change, river distribution, geological structure as well as the local terrain. The results show that (1) the land subsidence with the average velocity of 50 mm/year occurred in the low elevation area in the front part of the delta and the coastal area, and the area of the regions subsiding fast than 30 mm/year between 2006 and 2011 is larger than 122 km2; (2) the subsidence order and area estimated in this study are both much larger than that measured in previous studies; (3) the areas along rivers suffered from surface subsidence, due to the thick soft soil layer and frequent human interference; (4) the geological evolution is the intrinsic factor of the surface subsidence in the PRD, but human interference (reclamation, ground water extraction and urban construction) extends the subsiding area and increases the subsiding rate.

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Analysis on Mesoscopic Dynamic of Soft Soil Foundation in the Pearl River Delta Region Based on the Vacuum Preloading Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.100 ◽

2012 ◽

Vol 594-597 ◽

pp. 100-104

Author(s):

Jing Song ◽

Ren Yi Yue ◽

Peng Zhang

Keyword(s):

Pearl River Delta ◽

Fine Particles ◽

Soft Soil ◽

River Delta ◽

Pearl River ◽

Pearl River Delta Region ◽

Delta Region ◽

Vacuum Preloading ◽

Soil Foundation ◽

Soft Soil Foundation

The behavior of particle migration on soft soil foundation in Pearl River Delta region is analyzed considering the mesoscopic dynamic with vacuum preloading method. The numerical predictions are compared with the fine particle data in terms of settlements, horizontal displacements and vacuum degree of horizontal preloading. The repercussions of including the displacements law of fine particles are also studied. It is found that the analysis considering displacements law results in consolidation by rose diagram of particle migration, which is related to the consolidation of the vacuum preloading of soft soil foundation in Pearl River Delta region. It is apparently inconsistent with the vacuum preloading of the drainage which results from the fine particles migration, but it is fully justified by the fact that the real soil consolidation coordinates corrected for rose diagram obtained.

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The Strength Calculation Method of Foundation Treated with Sand Well

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.919-921.805 ◽

2014 ◽

Vol 919-921 ◽

pp. 805-808

Author(s):

Yu Cheng Zhang ◽

Hai Ying Hu ◽

Zhong Ming Huang

Keyword(s):

Calculation Method ◽

Pearl River Delta ◽

Soft Soil ◽

River Delta ◽

Pearl River ◽

Foundation Treatment ◽

The Pearl River Delta ◽

Soil Foundation ◽

Soft Soil Foundation ◽

The Pearl River

Due to the characteristics of the physical mechanical properties of soft ground, reasonable foundation treatments are usually necessary before it meets the need of foundation deformation and load requirements. How to choose a reasonable foundation treatment method which has obvious virtues of economical expenditure and shorter construction period is an urgent problem emerging in engineering construction in the Pearl River Delta. While drainage sand well is used widely in soft soil foundation treatment in the Pearl River Delta. In this paper, a simplified calculation method is proposed to calculate the strength of soft soil foundation treated by sand well after drainage consolidation.

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