1. Collapsibility, composition, and microfabric of the coastal zone loess around the Bohai Sea, China.
- Author
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Zhang, Weipeng, Sun, Yongfu, Chen, Wenwu, Song, Yupeng, and Zhang, Jingke
- Subjects
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LOESS , *PLATEAUS , *COASTS , *PARTICLE size distribution , *PORE size distribution , *SPECIFIC gravity , *PARTICULATE matter - Abstract
Coastal loess is a special loess deposit that is distributed around the Bohai Sea. The primary objective of this study was to investigate the physical index, mineralogical characteristics and collapse potential of coastal loess. The secondary objective was to survey the effect of fine silt particles (particle size 5–10 μm, 6.64–7.64φ) on the collapse process. We tested the specific gravity, moisture content, dry density, Atterberg limits, grain size distribution, mineralogy, and collapsibility characteristics in a laboratory; generated scanning electron microscopy (SEM) images; and performed Mercury intrusion porosometry (MIP) tests. The results of this investigation indicated that coastal loess has a moderately severe collapse potential. The collapsibility coefficient decreases with an increase in the initial water content; it initially increases and then decreases with an increase in vertical pressure. As revealed by the MIP test, the collapse produces a smaller porosity, and the middle pores are primarily responsible for the collapse. The relationship of the collapsibility coefficient and particles with a diameter < 10 μm reveals that fine silt particles (particle size 5–10 μm, 6.64–7.64φ) and clay particles (particle size < 5 μm, >7.64φ) have the same tendency in terms of their effect on collapse. These results and analyses are important to improve the engineering construction safety in coastal zone loess areas and achieve a better understanding of loess properties compared with loess from a typical loess-paleosol section. • Surveyed the particle and pore size distribution, Atterberg limits and mineralogical characteristics of Coastal loess. • Obtained the collapsibility of Coastal loess, and proposed the relationship between collapsibility coefficient and micro indexes based on the results of SEM and MIP tests. • Discussed the effect of fine silt particles (5-10 μm) on the collapse process. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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