Document Type
Journal Article
Publication Title
Journal of Rock Mechanics and Geotechnical Engineering
Volume
14
Issue
4
First Page
1266
Last Page
1279
Publisher
Elsevier
School
School of Engineering
RAS ID
52221
Funders
National Natural Science Foundation of China
Grant Number
2019P05
Abstract
The long-term settlement of calcareous sand foundations caused by daily periodic fluctuations has become a significant geological hazard, but effective monitoring tools to capture the deformation profiles are still rarely reported. In this study, a laboratory model test and an in situ monitoring test were conducted. An optical frequency domain reflectometer (OFDR) with high spatial resolution (1 mm) and high accuracy (±10-6) was used to record the soil strain responses to groundwater table and varied loads. The results indicated that the fiber-optic measurements can accurately locate the swelling and compressive zones. During the loading process, the interlock between calcareous sand particles was detected, which increased the internal friction angle of soil. The foundation deformation above the sliding surface was dominated by compression, and the soil was continuously compressed beneath the sliding surface. After 26–48 h, calcareous sand swelling occurred gradually above the water table, which was primarily dependent on capillary water. The swelling of the soil beneath the groundwater table was completed rapidly within less than 2 h. When the groundwater table and load remain constant, the compression creep behavior can be described by the Yasong-Wang model with R2 = 0.993. The daily periodically varying in situ deformation of calcareous sand primarily occurs between the highest and lowest groundwater tables, i.e. 4.2–6.2 m deep. The tuff interlayers with poor water absorption capacity do not swell or compress, but they produce compressive strain under the influence of deformed calcareous sand layers.
DOI
10.1016/j.jrmge.2021.08.003
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Cao, D., Shukla, S. K., Yang, L., Guo, C., Wu, J., & Wang, F. (2022). Responses of calcareous sand foundations to variations of groundwater table and applied loads. Journal of Rock Mechanics and Geotechnical Engineering, 14(4), 1266-1279. https://doi.org/10.1016/j.jrmge.2021.08.003