Article
Engineering, Geological
Haijun Hu, Philipp Braun, Pierre Delage, Siavash Ghabezloo
Summary: By conducting transient experiments and analyzing the data obtained, the transversely isotropic poroelastic parameters and permeability of Opalinus Clay were successfully determined, showing strong anisotropy in some parameters and close values in others. These results contribute to the existing database of hydromechanical properties of Opalinus Clay.
Article
Engineering, Mechanical
Kristian Krabbenhoft
Summary: The new total stress failure criterion takes into account both isotropic and anisotropic soils under undrained conditions, and has been validated with reported data from various types of tests.
JOURNAL OF ENGINEERING MECHANICS
(2021)
Article
Engineering, Geological
Eleonora Crisci, Alessio Ferrari, Silvio B. Giger, Lyesse Laloui
Summary: By adopting a layered structure with an alternation of two kinds of layers, it is possible to capture most of the variability in the studied geomechanical properties of Opalinus Clay.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Engineering, Geological
Xinyu Liu, Xianwei Zhang, Lingwei Kong, Shixing Zhang, Gang Wang
Summary: Noncoaxiality is crucial for accurately predicting the constitutive relationships of soils. Although the noncoaxiality of sand and clay has been extensively studied, there is still insufficient information about residual soil. This paper conducted systematic undrained hollow-cylinder torsional shear tests on natural granite residual soil (GRS) and found that the noncoaxial behavior of GRS depends on the principal-stress direction and the deviator stress. It also correlated the inherent anisotropy of the soil with its noncoaxial behavior and proposed empirical relationships for sand, but these relationships do not apply to GRS and soft clay.
Article
Engineering, Environmental
Zhanchao Yin, Qingsong Zhang, Xiao Zhang, Jiaqi Zhang, Xianghui Li
Summary: Currently, slurry-soil interface direct shear (IDS) tests and triaxial compression (TC) tests are used to determine the shear strength of grouted soil. However, previous studies have mainly focused on sandy soils and paid less attention to clayey soil. This study introduces two grouting test methods for fabricating grouted clay specimens suitable for TC and IDS testing. Findings show that outcomes obtained from IDS tests are unreliable, and using TC tests to obtain accurate shear strengths of grouted clay is crucial for predicting soil deformation and developing rational construction schemes.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2022)
Article
Engineering, Geological
Lang Liu, Silvio B. Giger, Derek Martin, Rick Chalaturnyk, Kristof Schuster, Nathan Deisman, Lukas Keller
Summary: Opalinus Clay is the designated host rock for a deep geological repository of radioactive waste in Switzerland. The determination of its geo-mechanical properties relies heavily on laboratory tests on small specimens. The pressuremeter tests were performed in Opalinus Clay to assess its in-situ elastic stiffness at a larger scale. The shear modulus of the Opalinus Clay is dependent on the expansion pressure and exhibits a nonlinear dependence on strain increment.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Construction & Building Technology
Xiaohua Bao, Yujun Huang, Zhiyang Jin, Xiong Xiao, Waiching Tang, Hongzhi Cui, Xiangsheng Chen
Summary: Reinforcing clay soil with carbon fibers can significantly improve shear strength and cohesion, with 3 wt% content of 6 mm fibers deemed most effective for enhancing strength.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Geological
Chunyong Jiang, Xuanming Ding, Huaqiang Fang, Jing Lian
Summary: Research has found that coral silt, a type of coral soil with over 50% silt content, is formed during land reclamation. The cyclic dynamic shear characteristics of coral silt are important for determining the seismic safety of reef infrastructures due to the frequent action of waves, wind, earthquakes, and other dynamic loads. Symmetrical and asymmetrical cyclic simple shear tests were conducted to investigate the cyclic behavior of coral silt, with emphasis on the static-cyclic shear stress coupling. Empirical formulas were proposed to estimate the undrained peak shear strength and critical state strength in monotonic simple shear tests. The CSR threshold value, ranging from 0.05 to 0.075, controlled the final failure in both symmetrical and asymmetrical-loading cyclic simple shear tests. The cyclic shear stress had a significant influence on the cyclic deformation, cyclic pore water pressure, cyclic strength, and cyclic shear modulus of coral silt.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2023)
Article
Engineering, Geological
Niloufar Mashhadiali, Fatemeh Molaei
Summary: This study proposes a theoretical model to predict the shear strength of anisotropic rocks based on the inclination of inherent structural weak planes. Triaxial and direct shear tests were conducted on shale samples to verify the anisotropic behavior. The experimental results showed a U-shape relationship between compressive strengths and inclination of bedding planes. Based on the Coulomb-Navier criterion, a theoretical model was derived to relate shear strength to the inclination of bedding planes. Direct shear tests confirmed the proposed criterion and showed shear anisotropy behavior.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2023)
Article
Engineering, Geological
Ji-Yun Chang, Shi-Jin Feng, Qi-Teng Zheng, Yang Shen
Summary: The dynamic shear mechanism of the composite liner system consisting of GMB and GCL is not clear due to limited dynamic test data. Results from cyclic shear tests suggest that the dynamic peak strength of the composite liner can generally be predicted with its static strength envelope. Proposed equations help accurately model the cyclic shear behavior, describing the dynamic softening mechanism and rate-dependent shear stiffnesses.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Engineering, Geological
Luis M. Garcia, Nuria M. Pinyol, Antonio Lloret, Edwin A. Soncco
Summary: This paper presents the influence of temperature on the residual strength by analyzing shearing tests carried out in a temperature-and velocity-controlled ring shear apparatus. Temperature changes were found to have a significant effect on the strength of clayey soils, while sandy soils were not reactive to temperature changes. The magnitude of the strength variation observed during cooling and heating was around 2 degrees for high plasticity soils. Shear strength reacts immediately to temperature changes and a new residual strength establishes soon.
ENGINEERING GEOLOGY
(2023)
Article
Chemistry, Physical
Xin Liang, Fang Yan, Yuliang Chen, Huiqin Wu, Peihuan Ye, Yuhuan Mo
Summary: The study focused on mechanical properties of recycled aggregate concrete (RAC) at different ages by testing direct shear strength and cube compressive strength of 264 standard cubes. It was found that the replacement ratio has minimal impact on crack patterns, with direct shear strength and residual strength varying with time and replacement ratio. The load-displacement curve of RAC at direct shearing showed distinct stages of elasticity, elastoplasticity, plasticity, and stabilization.
Article
Engineering, Geological
Xinyu Liu, Xianwei Zhang, Lingwei Kong, Ran An, Guofang Xu
Summary: This study found that natural residual soils exhibit significant anisotropy in strength, different from normally consolidated clays. To address this, two parameters were proposed to quantify the anisotropic strength of residual soils under general conditions.
Article
Engineering, Civil
Nguyen Thanh Duong, Motoyuki Suzuki
Summary: The shear strength behavior of overconsolidated clayey soil at different shear rates is complex and not yet fully understood, especially in terms of residual strength characteristics. The study found that the peak strength of overconsolidated and normally consolidated clays have opposite rate effects at fast shear displacement rates. Additionally, the cohesion and friction angles of overconsolidated clay vary at different shear rates both at peak and residual states.
PERIODICA POLYTECHNICA-CIVIL ENGINEERING
(2022)
Article
Engineering, Geological
Lei Fan, Meiwan Yu, Aiqing Wu, Yihu Zhang
Summary: Interactions between water and rocks are the main factors affecting the deformation of rock masses on sloped banks by reservoir impoundment. In this work, an in situ, hydromechanical (HM), true triaxial rock compression tester is developed to investigate the coupling response of reservoir bank rocks to changing groundwater levels.
QUARTERLY JOURNAL OF ENGINEERING GEOLOGY AND HYDROGEOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Mohamed Khatif Tawaf Mohamed Yusof, Ahmad Safuan A. Rashid, Mohd Faisal Abdul Khanan, Muhammad Zulkarnain Abdul Rahman, Wardatun Ahmar Abdul Manan, Roohollah Kalatehjari, Ali Dehghanbanadaki
Summary: This study investigates the effects of climate change on landslide susceptibility mapping (LSM) using a case study on Penang Island in Malaysia. The results show that future rainfall and temperatures are expected to increase, especially under a higher climate change scenario. LSM can help local authorities identify critical areas for monitoring and responding to landslide risks caused by climate change.
PHYSICS AND CHEMISTRY OF THE EARTH
(2024)
Article
Geosciences, Multidisciplinary
Shivam Pandey, Ajay Singh, Anuj Kumar, Inderjeet Tyagi, Rama Rao Karri, Rama Gaur, Hamedreza Javadian, Monu Verma
Summary: This research compares the effectiveness of hydrothermally produced ZnO and SnO2 nanocatalysts in degrading p-nitrophenol, a noxious chemical in water. The study finds that ZnO catalyst has better degradation efficiency compared to SnO2 catalyst. Detailed investigation reveals the optimal conditions for degrading p-nitrophenol using ZnO photocatalysts.
PHYSICS AND CHEMISTRY OF THE EARTH
(2024)
Article
Geosciences, Multidisciplinary
Muhammad Farhan Ul Moazzam, Sudeep Thakuri, Ghani Rahman, Byung Gul Lee
Summary: This study explores the elevation dependent warming in the Indus River Basin and its impacts on cryospheric and hydrological changes. The results show significant warming trends in the Tmax and Tmin in the upper Indus Basin, with a more prominent trend observed during the winter season for Tmax. These consistent warming trends can have harmful impacts on the cryosphere of the region, leading to water scarcity and extreme droughts.
PHYSICS AND CHEMISTRY OF THE EARTH
(2024)