LI Ying, WEI Jie, LUO Huajin, et al. Cracks Development in Purple Soil Bunds Under Water Evaporation and Its Influencing Factors[J]. 2022, 36(1): 38-44.
DOI:
LI Ying, WEI Jie, LUO Huajin, et al. Cracks Development in Purple Soil Bunds Under Water Evaporation and Its Influencing Factors[J]. 2022, 36(1): 38-44. DOI: 10.13870/j.cnki.stbcxb.2022.01.006.
Cracks Development in Purple Soil Bunds Under Water Evaporation and Its Influencing Factors
The development of soil cracks endangers the stability of soil bund
further influences soil conservation. In order to reveal the law of crack development and the main influencing factors under water evaporation
a typical purple soil bund on sloping farmland in Beibei district of Chongqing was chosen to sample and test. Different levels of initial water contents (25%
30%
35%)
dry densities (1.3
1.4
1.5 g/cm3) and reinforcements (0.05%
0.15%
0.25%) were defined to model the crack development process of purple soil bunds by using a set of simulated bunds. The crack development intensity
complexity indexes and the relationship between crack development and (initial) water content
dry density
and reinforcement were studied through image analysis. The results showed that the crack development process could be divided into three stages under water evaporation in terms of the initial stage
rapid crack expansion and stabilization. Under different initial water contents
the cracks intensity and complexity of all specimens increased rapidly with the decreasing water evaporation
and then tended to be stable at the water content of 12%. Dry density was an important factor impacting soil shrinkage and swell. Under the same initial water content
the cracks intensity and complexity increased as dry density increasing. The amount of reinforcement of polypropylene fiber was inversely proportional to the degree of cracks development. Comparatively
the initial water content had a great impact on the early stage of crack development in the process of water evaporation
but after the cracks began
the water content became a more important impacting factor
followed by the dry density and reinforcement. These results are expected to provide a basis for the design
construction
maintenance and management of soil bunds in purple soil area.
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Soil-water Characteristics and Shear Strength of Root-soil Composites from Purple-soiled Bunds
Related Author
ZHENG Wenjiao
WEI Jie
TANG Qiang
LI Jinlin
HE Ying
Related Institution
Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, School of Geography and Tourism, Chongqing Normal University
Chongqing Observation and Research Station of Earth Surface Ecological Processes in the Three Gorges Reservoir Area
Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences