Article
Environmental Sciences
Guanghui Xu, Qiang Zheng, Xiutao Yang, Rui Yu, Yong Yu
Summary: This study investigated the migration of three commonly used ENPs in different soil types under freeze-thaw cycles. The migration rate of ENPs was found to be highest in black soil, with CeO2-NPs demonstrating the highest mobility among the three ENPs. Higher moisture content and lower freezing temperature were found to increase the migration depth and affect the behavior of ENPs in soils.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Construction & Building Technology
Fujun Niu, Junlin He, Haiqiang Jiang, Chenglong Jiao
Summary: The paper aims to develop a constitutive model that considers freeze-thaw damage and mesoscopic structural damage during loading to predict the mechanical properties of freeze-thawed concrete. The study analyzes the freeze-thaw damage mechanism and the load damage mechanism of concrete to establish a macro-mesoscopic constitutive relationship. The model takes into account the inhomogeneous deformations between the structural body and the frictional band, and has been validated through experimental results.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Mechanical
Yue Zhai, Fandong Meng, Yubai Li, Yan Li, Ruifeng Zhao, Yunsheng Zhang
Summary: This study focuses on the micro-damage, macro-fracture characteristics, and dynamic properties of Tongchuan sandstone in northwest China after freeze-thaw. The results show that the impact loading has a greater effect on the rocks compared to freeze-thaw, and this effect weakens as the rocks soften. A new damage constitutive model considering various forms of dissipated energy has been proposed.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Computer Science, Interdisciplinary Applications
Huimei Zhang, Chao Yuan, Gengshe Yang, Luyuan Wu, Chuan Peng, Wanjun Ye, Yanjun Shen, Hossein Moayedi
Summary: In this study, a computational model was developed to analyze rock deformation and failure characteristics under freeze-thaw cycles and loading, considering the impact of confining pressure and material defects. The model successfully reflects the internal mechanism of freeze-thaw damage and selected physical variables, demonstrating adaptability. The model also predicts an evolution curve of total damage, showing the closure, initiation, propagation and coalescence of internal microcracks, as well as rock failure mechanisms.
ENGINEERING WITH COMPUTERS
(2021)
Article
Engineering, Environmental
Zipeng Qin, Yuanming Lai, Yan Tian, Mingyi Zhang
Summary: By studying the instability of irrigation reservoir bank slopes in cold regions caused by freeze-thaw cycles, a numerical model was established to predict the slope failure based on temperature, cracks generation, and safety factors with hydrothermal variation. The results show a 10.43% decrease in safety factor after 5 freeze-thaw cycles, indicating an accelerated slope instability.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Environmental
Zhemin You, Wei Wen, Yuanming Lai, Mingyi Zhang, Jing Zhang
Summary: This study investigates the impact of moisture and salt migration and accumulation on pipeline corrosion. Three barrier measure models were established and laboratory tests were conducted to analyze the barrier effect of different measures during freeze-thaw cycles. The results show that impermeable geotextile barrier and gravel replacement can effectively prevent moisture and salt migration and corrosion to the pipeline.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yu-Zhi Zhang, Xiao-Dong Zhu, Wen-Long Liu, Hai-Yong Wang, Wei Jiang
Summary: The research investigated moisture migration features and mesoscopic mechanism of coarse-grained fillings with different initial water contents under short-term freeze-thaw cycles. Results showed that initial water content influenced the migration process, with external water replenishment and liquid water migration height inversely proportional to initial water content. Freeze-thaw cycles and dynamic loads led to thaw settlement compression deformations.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2022)
Article
Environmental Sciences
Shuping Yang, Zhibin He, Longfei Chen
Summary: The frequency and intensity of freeze-thaw cycles are expected to increase with climate change, affecting soil carbon turnover and CO2 and CH4 fluxes. This study explored the effects of freeze-thaw cycles on CO2 and CH4 fluxes in an alpine forest ecosystem. The results showed that freeze-thaw cycles significantly affected CO2 and CH4 fluxes, promoting CO2 emission during thawing and reducing CH4 uptake during freezing. Freezing temperature and soil moisture had significant impacts on CO2 and CH4 fluxes, and their interaction also had significant effects.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Biodiversity Conservation
Shuping Yang, Zhibin He, Longfei Chen
Summary: The study reveals that soil carbon emissions from subalpine ecosystems are influenced by freeze-thaw cycles and soil moisture levels. An increase in the number of freeze-thaw cycles and soil moisture can lead to a potential increase in soil CO2 emissions and CH4 uptakes.
ECOLOGICAL INDICATORS
(2023)
Article
Engineering, Environmental
Wangtao Jiang, Yuanming Lai, Fan Yu, Qinguo Ma, Haiqiang Jiang
Summary: This paper conducted uniaxial compression tests on red sandstones under different numbers of freeze-thaw cycles (FTCs), and established the relationships between mechanical parameters and the number of FTCs. The method for determining the fully compacted point was proposed, and a new damage constitutive model simulating the whole deformation process of rock subjected to FTCs was proposed. The proposed model showed better consistency with experimental data compared to the existing models, and the two existing models can be improved to be more versatile. This finding enriches the research of rock in constitutive modeling in cold regions.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2023)
Article
Mechanics
Xiangzhen Meng, Huimei Zhang, Chao Yuan, Yugen Li, Xiaoyu Liu, Shiguan Chen, Yanjun Shen
Summary: A damage constitutive prediction model of frozen-thawed rock was established based on the strain equivalent hypothesis in this study. The rationality of the model was verified through the analysis of the microstructure and macroscopic mechanical properties of red sandstone. The results showed that as the number of freeze-thaw cycles increased, the damage to the rock aggravated, leading to a decrease in compressive strength and resistance to deformation.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Environmental
Junlin He, Fujun Niu, Fei Luo, Haiqiang Jiang, Peifeng He, Xin Ju
Summary: It is important to study the mechanical properties of red-bed soft rocks and establish a constitutive model for the deformation and evaluation of red-bed landslides in seasonally frozen ground regions. Triaxial tests are conducted to investigate the effects of freeze-thaw cycles on the rock's strength and ductile damage characteristics. The results show that freeze-thaw cycles significantly reduce the rock's strength and enhance its ductile damage characteristics. A constitutive model is proposed based on the binary-medium structure and homogenization theory, considering the initial freeze-thaw damage and the inhomogeneous deformation characteristics of the rock.
COLD REGIONS SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Lu Ren, Lun-Yang Zhao, Fu -Jun Niu
Summary: In cold regions, the combined action of freeze-thaw cycling and loading has a significant impact on the stability of engineering structures. This study proposes a physically-based elastoplastic damage model for quasi-brittle geomaterials under freeze-thaw cycles and loading within the framework of irreversible thermodynamics. The model describes the entire deformation and failure process of the material and introduces a new nonlinear evolution law of freeze-thaw damage based on micro-mechanics.
APPLIED MATHEMATICAL MODELLING
(2022)
Article
Chemistry, Physical
Di Yu, Haosen Jing, Jianan Liu
Summary: This paper focuses on the freeze-thaw damage of asphalt pavement and conducts X-ray computed tomography experiments on asphalt mixture before and after freezing and thawing. The results show that the characteristic mean value of the 9th cycle is the irreversible limit of freeze-thaw damage. The non-resilience after the increase in large void area is the fundamental reason for the accumulation of freeze-thaw damage. The source of void damage shifts from large voids to small voids, and the middle-stage is a critical stage of freeze-thaw damage. This research provides a quantitative evaluation of the internal freeze-thaw damage process of asphalt mixture and proposes a morphological theory of the evolution of void damage based on an equivalent ellipse, which contributes to a better understanding of the freezing-thawing damage law of asphalt pavement.
Article
Construction & Building Technology
Xu Gong, Hongfa Yu, Chengyou Wu
Summary: The damage form, stress-strain relationship, quasi-static mechanics performance, and deformation performance of concrete under freezing-thawing cycles were studied. It was found that freezing-thawing cycles caused severe damage to concrete but also increased its ductility. A linear relationship model was established to accurately describe the mechanical behavior of concrete under freezing-thawing cycles.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Mechanics
Rui Zhang, Cheng Zhao, Jinquan Xing, Jialun Niu, Huiguan Chen, Yuan Qian
Summary: The presence of inherent microcracks in granite poses challenges to accurately describe crack propagation and fracture behaviors, which are crucial in engineering applications. Our findings suggest that crack propagation is competitively affected by flaw geometry and inherent microcracks. During semi-circular bending, the width of the fracture process zone is influenced by inherent microcracks, while the length is not. The existence of inherent microcracks widens the fracture process zone and increases its influence scope. The fracture process zone and isolated strain concentration caused by inherent microcracks merge to form a continuous fracture path. In addition, the size dependence of fracture toughness was discussed using simulation data.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Huiguan Chen, Cheng Zhao, Rui Zhang, Jinquan Xing, Lin Huang, Yuan Qian
Summary: This paragraph introduces the influence of moisture migration on crack initiation and defect propagation in jointed rock mass during freeze-thaw cycles, and proposes a macro-micro damage constitutive model to describe the behavior of jointed rock mass under freeze-thaw actions. The model considers different stages such as compaction deformation, elastic deformation, plastic deformation, and damage, and can accurately simulate the full stress-strain curves of jointed rock mass under freeze-thaw actions.
ENGINEERING FAILURE ANALYSIS
(2023)
