Article
Engineering, Geological
Luqing Zhao, Jianbing Peng, Penghui Ma, Yanqiu Leng, Zhe Ma
Summary: Freeze-thaw cycles lead to shear strength deterioration, which affects the stability of loess slopes in seasonal frozen regions. This study performed multiple freeze-thaw tests on natural loess, analyzing the relationship between shear strength index and particle microstructure characteristics. The results showed that changes in particle shape contributed the most to the deterioration of shear strength during the freeze-thaw cycles, followed by particle arrangement and distribution.
ENGINEERING GEOLOGY
(2023)
Article
Multidisciplinary Sciences
Ying-jun Jiang, Chen-yang Ni, Hong-wei Sha, Zong-hua Li, Lu-yao Cai
Summary: The study found that the mechanical strength of cement-improved loess degrades continuously under dry-wet and freeze-thaw cycles, but tends to stabilize after a certain number of cycles.
Article
Engineering, Environmental
Jian Xu, Zhilang You, Fei Sun, Yanfeng Li, Jianjun Cheng, Lei Qu
Summary: Freezing-thawing cycles and salinization are two important factors causing deterioration of loess. This study investigated the unconfined compressive strengths of remolded loess with different Na2SO4 contents and freezing-thawing cycles, and analyzed the pore size distribution. A constitutive model was proposed to establish the relationship between unconfined compressive strength and porosity. The results showed a linear decrease in strength with Na2SO4 contents and an exponential decrease with freezing-thawing cycles. The study provides valuable insights for engineering construction in the Chinese Loess Plateau.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2023)
Article
Construction & Building Technology
Yi Wang, Junhui Li, Tamon Ueda, Dawei Zhang, Jun Deng
Summary: Low water-to-cement ratio specimens showed stable strength and modulus after freeze thaw cycles, while high water-to-cement ratio specimens degraded gradually. The connectivity of specimens had limited increase in frost damage incurred with higher NaCl concentrations, mainly due to the reversible formation of Friedel's salt.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Environmental Sciences
Qifeng Li, Bing Dang, Dandan Li, Xiaoying Hu
Summary: Earthen sites have significant historical and cultural value, but erosion often causes their destruction. Solidification of calcined ginger nuts can enhance the strength of soil to protect these sites. However, the degradation of solidified soil strength after dry-wet and freeze-thaw cycles is unclear.
Article
Engineering, Environmental
Liyun Tang, Gang Li, Tao Luo, Long Jin, Yongtang Yu, Qiang Sun, Guoyu Li
Summary: The growth and melting of internal ice crystals lead to the deterioration of the shear strength of soil-rock mixture (S-RM) after freeze-thaw cycles. Through simulation and experiments, it was found that the thickness of shear band, fluctuation value of failure surface, and shear strength are related to the rock content, with the most significant changes observed at a rock content of 45%. Fractal theory was introduced to reveal the strength deterioration mechanism of S-RM.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Environmental
Fang Zheng, Shengjun Shao, Songhe Wang
Summary: The study found that freeze-thaw cycles lead to a temporary decrease followed by stabilization in the shear strength of recompacted loess, with varying effects based on different b-values. Freeze-thaw has minimal impact on the shear strength parameters, with cohesion decreasing and internal friction angle remaining relatively stable.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2021)
Article
Polymer Science
Wensong Wang, Guansen Cao, Ye Li, Yuxi Zhou, Ting Lu, Binbin Zheng, Weile Geng
Summary: This study examines the mechanical properties of lime-stabilized basalt fiber-reinforced loess under freeze-thaw cycles. The results demonstrate that the addition of basalt fiber and lime enhances the strength of loess and improves its resistance to freeze-thaw damage. Additionally, it is found that there is a linear relationship between UCS and Vp, and Vp can be used to estimate UCS.
Article
Engineering, Environmental
Jinke Yuan, Changwen Ye, Jinfei Yang, Zhenbin Xie, Jiancheng Liu, Sheng Wang, Yunpeng Liu
Summary: Development of durable anchorage systems for slope support in high-cold and high-altitude areas is a global research hotspot. This study investigated the deterioration mechanism of bond and anchorage performance of grouted rock bolts under freeze-thaw cycles. The results showed a decrease in anchoring force after 30 freeze-thaw cycles, with the highest anchor stress in the middle part of the anchorage, likely leading to shearing failure.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2021)
Article
Engineering, Geological
Yu-Ling Yang, Tao Zhang, Song-Yu Liu, Jun-Hui Luo
Summary: This study aims to investigate the mechanical properties and deterioration mechanism of carbonaceous mudstone exposed to wetting-drying cycles. The experimental results showed that the stress-strain characteristic of the mudstone changed from "brittle" to "ductile" with an increase in wetting-drying cycles. The unconfined compressive strength and shear strength significantly decreased within the first 10 cycles and then reached a relatively stable value. The residual strength exhibited an opposite trend to the unconfined compressive strength and could be described using an exponential function. Both cohesion and friction angle decreased with the increasing wetting-drying cycles. Scanning electron microscope analysis revealed that the wetting-drying cycles resulted in an unstable microstructure with larger pore size and layer spacing. The loss or dissolution of soluble minerals/salts had negative impacts on the stability of the microstructure and accelerated the deterioration of mechanical properties.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Construction & Building Technology
Banglong Xie, Wuyu Zhang, Xianglong Sun, Yuling Huang, Leqing Liu
Summary: This research presents a series of laboratory tests on both undisturbed and remolded loess to investigate the influence of freeze-thaw cycles on the compressive strength and internal structure of loess. The test results showed that the compressive strength of loess initially increased and then decreased with increasing freeze-thaw cycles. The study also found that freezing and thawing had less effect on loess minerals. These findings have important implications for the protection and management of loess buildings in Qinghai.
Article
Construction & Building Technology
Hui Song, Jinwei Yao, Junzheng Xiang
Summary: Research has found that under F-T conditions, the compressive strength and dynamic elastic modulus of pervious concrete decrease with increasing cycles, and damage in salt water is more severe than in water. SEM results indicate that debonding at the interface between aggregate and cement is the primary cause of pervious concrete deterioration.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Engineering, Geological
Charles W. W. Ng, Yikai Wang, Shuai Zhang, Zeyu Li, Qi Zhang, Haiyi Zhong
Summary: This study investigates the thermal, hydraulic, and mechanical response of an unsaturated slope under cyclic freeze-thaw cycles. The results show that the freeze-thaw process softens the slope and induces downslope movement, as well as generates surface and deep cracks.
CANADIAN GEOTECHNICAL JOURNAL
(2023)
Article
Engineering, Geological
Charles W. W. Ng, Yikai Wang, Shuai Zhang, Zeyu Li, Qi Zhang, Haiyi Zhong
Summary: In this study, a novel in-flight freeze-thaw system was used to investigate the thermal, hydraulic, and mechanical response of a typical unsaturated slope under seven freeze-thaw cycles in the centrifuge. The test results showed that the suction at the freezing front can be up to about 1 MPa, and subsequent thawing reduces the suction to 9 kPa, about 60% lower than the initial unfrozen state. The repeated freeze-thaw action generates significant fractures at the soil surface and deep cracks due to tensile rupture.
CANADIAN GEOTECHNICAL JOURNAL
(2023)
Article
Construction & Building Technology
Qi Liu, Ze Zhang, Shengrong Zhang, Xianglong Li, Haichao Long, Xiangxi Meng, Andrey Melnikov, Leonid Gagarin
Summary: This study simulates the effects of freeze-thaw weathering on sand and gravel materials through cycling tests. The study finds that the equivalent diameter and fractal dimension show a strong correlation with long-term strength, while roundness, aspect ratio, and ellipticity show weak correlation. Hence, improving the morphological characteristics of sand and gravel materials can enhance their resistance to freeze-thaw damage in engineering applications.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2023)
