Dry-wet Cycle Test Study of Size Effect on Surface Cracks and Shear Strength of Expansive Soil

Feng Rong ； Anti Liu ； Liangsheng Chen

《International Core Journal of Engineering》 6卷11期 (2020/11) Pp. 64-73

https://doi.org/10.6919/ICJE.202011_6(11).0010

摘要

In order to study the effects of different sizes of expansive soil specimens on the surface cracks and shear strength under the action of dry-wet cycles, ring cutter reshaped specimens with different sizes of 61.8mm, 100mm, and 200mm in diameter were prepared and carried out under the action of dry-wet cycles Quantitative analysis of the three visual indicators of the number of surface cracks, average width and average length, and explore the evolution of peak strength, residual strength and strength attenuation rate with the number of wet and dry cycles. Studies have shown that: the development of cracks is manifested in three stages: rapid ascent, slow development and stable cracks. The crack incubation period is not obvious, and the size effect will affect the distribution and development of the cracks; the size effect and the dry-wet cycle mainly cause the peak strength The change in the residual strength has nothing to do with the residual strength; the dry-wet cycle causes a large attenuation rate of the peak cohesive force, followed by the peak internal friction angle attenuation rate, and the residual strength basically has no attenuation. The peak cohesive force is the main cause of the strength attenuation during the dry-wet cycle Parameter index.

關鍵字

Surface fissure ； Dry-wet cycle ； Peak strength ； Residual strength ； Attenuation rate

參考文獻

Julina M, Thyagaraj T. Quantification of desiccation cracks using X-ray tomography for tracing shrinkage path of compacted expansive soil[J]. Acta Geotechnica, 2018(1).

Peron H, Hueckel T, Laloui L, et al. Fundamentals of desiccation cracking of fine-grained soils: experimental characterisation and mechanisms identification[J]. Canadian Geotechnical Journal, 2009 (10).

Z. Huang, B. Wei, L. Zhang , et al. Surface Crack Development Rules and Shear Strength of Compacted Expansive Soil Due to Dry–Wet Cycles[J]. Geotechnical and Geological Engineering, 2018 (4).

J. Xiao, H. Yang, J. Zhang, et al. Properties of Drained Shear Strength of Expansive Soil Considering Low Stresses and Its Influencing Factors[J]. International Journal of Civil Engineering, 2017(10).

C. Liu, C.S. Tang, B. Shi, et al. Automatic quantification of crack patterns by image processing[J]. Computers & Geosciences, 2013(4).