This page has only limited features, please log in for full access.
Single-edge notched beam specimens have been used widely to determine the fracture toughness KIC of compacted clays under three-point bending loading. However, this specimen type is not very suitable for the material with low strength. In this study, notched semi-circular bend specimens were employed to determine the KIC of a compacted clay, the effects of initial notch length, specimen thickness, moisture content and dry density on KIC were investigated. Based on the testing results, the ratio of initial notch length to specimen radius a0/R = 0.3–0.5 was suggested. There was no remarkable thickness-dependent size effect for the compacted clay. To investigate the relationship between the KIC and tensile strength σt of the compacted clay, unnotched semi-circular bend specimens were employed for determining the σt. It is concluded that there is a good linear relationship between these two parameters. According to the discussion on the testing results of different compacted clays, an empirical formula KIC = 0.3283σt was obtained, which can be used to estimate the KIC with σt of directly compacted clays. Additionally, the size of fracture process zone of the compacted clay was calculated by an estimation method.
Junjie Wang; Shiyuan Huang; Wanli Guo; Zhenfeng Qiu; Kai Kang. Experimental study on fracture toughness of a compacted clay using semi-circular bend specimen. Engineering Fracture Mechanics 2019, 224, 106814 .
AMA StyleJunjie Wang, Shiyuan Huang, Wanli Guo, Zhenfeng Qiu, Kai Kang. Experimental study on fracture toughness of a compacted clay using semi-circular bend specimen. Engineering Fracture Mechanics. 2019; 224 ():106814.
Chicago/Turabian StyleJunjie Wang; Shiyuan Huang; Wanli Guo; Zhenfeng Qiu; Kai Kang. 2019. "Experimental study on fracture toughness of a compacted clay using semi-circular bend specimen." Engineering Fracture Mechanics 224, no. : 106814.
The mountainous region of Greater Sochi, including the Olympic ski-jump complex area, located in the northern Caucasus, is always subjected to landslides. The weathered mudstone of low strength and potential high-intensity earthquakes are considered as the crucial factors causing slope instability in the ski-jump complex area. This study aims to conduct a seismic slope instability map of the area. A slope map was derived from a digital elevation model (DEM) and calculated using ArcGIS. The numerical modelling of slope stability with various slope angles was conducted using Geostudio. The Spencer method was applied to calculate the slope safety factors (Fs). The pseudostatic analysis was used to compute Fs considering seismic effect. A good correlation between Fs and slope angle was found. Combining these data, sets slope instability maps were achieved. Newmark displacement maps were also drawn according to empirical regression equations. The result shows that the static safety factor map corresponds to the existing slope instability locations in a shallow landslide inventory map. The seismic safety factor maps and Newmark displacement maps may be applied to predict potential landslides of the study area in the case of earthquake occurrence.
Kai Kang; Andrey Ponomarev; Oleg Zerkal; Shiyuan Huang; Qigen Lin. Shallow Landslide Susceptibility Mapping in Sochi Ski-Jump Area Using GIS and Numerical Modelling. ISPRS International Journal of Geo-Information 2019, 8, 148 .
AMA StyleKai Kang, Andrey Ponomarev, Oleg Zerkal, Shiyuan Huang, Qigen Lin. Shallow Landslide Susceptibility Mapping in Sochi Ski-Jump Area Using GIS and Numerical Modelling. ISPRS International Journal of Geo-Information. 2019; 8 (3):148.
Chicago/Turabian StyleKai Kang; Andrey Ponomarev; Oleg Zerkal; Shiyuan Huang; Qigen Lin. 2019. "Shallow Landslide Susceptibility Mapping in Sochi Ski-Jump Area Using GIS and Numerical Modelling." ISPRS International Journal of Geo-Information 8, no. 3: 148.
The influence of water on the mechanical properties of rock is vital for determining the rock stability when subjected to changes of water conditions. In this paper, a series of uniaxial compression tests were conducted to investigate effects of cyclic wetting and drying on the mechanical properties of sandstone and mudstone collected from Chongqing city, China. The results showed that both elastic modulus and uniaxial compressive strength of sandstone and mudstone were reduced by wetting and drying cycles, and that the degradation rate of the two mechanic parameters of mudstone was always larger than sandstone. The parameters, including water adsorption, degradation degree of elastic modulus, degradation degree of uniaxial compressive strength, increase with the increase of the wetting-drying cycles (N). The relationship between these three parameters and the value of N + 1 could be well fitted by logarithmic curves. The average degradation degree was also used to describe the degradation of per time wetting-drying cycles. It is found that the average degradation degree of elastic modulus and uniaxial compressive strength decrease with the increase of wetting-drying cycles. Moreover, the relationships between the mechanical properties and the porosity are presented, which can be fitted by linear curves. In the cyclic wetting-drying process, the elastic modulus and the uniaxial compressive strength decreased with the porosity increasing, and the degradation rates of sandstone mechanic parameters were higher than those of mudstone.
Shiyuan Huang; Junjie Wang; Zhenfeng Qiu; Kai Kang. Effects of Cyclic Wetting-Drying Conditions on Elastic Modulus and Compressive Strength of Sandstone and Mudstone. Processes 2018, 6, 234 .
AMA StyleShiyuan Huang, Junjie Wang, Zhenfeng Qiu, Kai Kang. Effects of Cyclic Wetting-Drying Conditions on Elastic Modulus and Compressive Strength of Sandstone and Mudstone. Processes. 2018; 6 (12):234.
Chicago/Turabian StyleShiyuan Huang; Junjie Wang; Zhenfeng Qiu; Kai Kang. 2018. "Effects of Cyclic Wetting-Drying Conditions on Elastic Modulus and Compressive Strength of Sandstone and Mudstone." Processes 6, no. 12: 234.
Zhenfeng Qiu; Junjie Wang; Shiyuan Huang; Jiping Bai. Wetting-induced axial and volumetric strains of a sandstone mudstone particle mixture. Marine Georesources & Geotechnology 2018, 37, 36 -44.
AMA StyleZhenfeng Qiu, Junjie Wang, Shiyuan Huang, Jiping Bai. Wetting-induced axial and volumetric strains of a sandstone mudstone particle mixture. Marine Georesources & Geotechnology. 2018; 37 (1):36-44.
Chicago/Turabian StyleZhenfeng Qiu; Junjie Wang; Shiyuan Huang; Jiping Bai. 2018. "Wetting-induced axial and volumetric strains of a sandstone mudstone particle mixture." Marine Georesources & Geotechnology 37, no. 1: 36-44.
Jun-Jie Wang; Shiyuan Huang; Jun-Feng Hu. Mode II fracture toughness of a clay mixed with sand. Engineering Fracture Mechanics 2016, 165, 19 -23.
AMA StyleJun-Jie Wang, Shiyuan Huang, Jun-Feng Hu. Mode II fracture toughness of a clay mixed with sand. Engineering Fracture Mechanics. 2016; 165 ():19-23.
Chicago/Turabian StyleJun-Jie Wang; Shiyuan Huang; Jun-Feng Hu. 2016. "Mode II fracture toughness of a clay mixed with sand." Engineering Fracture Mechanics 165, no. : 19-23.
Fracture toughness (KIC) is a very important parameter to evaluate fracture behavior of materials. Three-point bending (TPB) test on a single edge cracked beam (SECB) is often used to determine the value of KIC of soils. Depth of initial crack (a) of the SECB specimen may affect the tested value of KIC, limit of crack depth is therefore necessary in order to obtain the value of KIC. In this study, a red clay, distributed widely in south-west of China, was used to investigate the limit. Three-group TPB tests on 63 SECB specimens with different dimensions and properties were carried out. Based on the testing results, the limit of crack depth for the clay, i.e. the ratio of initial crack depth to specimen width a/W = 0.3 to 0.6, was suggested.
Jun-Jie Wang; Shiyuan Huang; Jun-Feng H U. Limit of crack depth in KIC testing for a clay. Engineering Fracture Mechanics 2016, 164, 19 -23.
AMA StyleJun-Jie Wang, Shiyuan Huang, Jun-Feng H U. Limit of crack depth in KIC testing for a clay. Engineering Fracture Mechanics. 2016; 164 ():19-23.
Chicago/Turabian StyleJun-Jie Wang; Shiyuan Huang; Jun-Feng H U. 2016. "Limit of crack depth in KIC testing for a clay." Engineering Fracture Mechanics 164, no. : 19-23.
The present study focuses on the compressibility and permeability characteristics of a crushed sandstone–mudstone particle mixture (SMPM). Two type of laboratory tests, which are compressibility–permeability test (CPT) and compressibility test only (CTO), are performed. Based on the test data, the effects of the seepage action on the compressibility and ones of the void ratio (e) on the permeability are analyzed. The rate of consolidation of the crushed SMPM is also discussed. The values of compressibility index (Cc) obtained from the CPT are greater about 1.32–4.81% than ones obtained from the CTO, but the values of preconsolidation stress (σp) obtained from the CPT are smaller about 2.34–9.83% than ones obtained from the CTO. The slope of fitting line of e∼logK (where K is the coefficient of permeability, and log is the logarithm to base 10), defined as the permeability index (Kc), ranges from 0.146 to 0.337 with an average of 0.226. The value of Cc/Kc, used to evaluate the rate of consolidation, ranges from 0.905 to 1.250 with an average of 1.031. The rate of consolidation of the crushed SMPM may be analyzed by Terzaghi’s theory due to the average value of Cc/Kc very close to 1.0.
Jun-Jie Wang; Shiyuan Huang; Yu-Mian Wen; Yang Yang; Ming-Wei Liu. Experimental study on interaction between compressibility and permeability of a crushed sandstone–mudstone particle mixture. Marine Georesources & Geotechnology 2016, 35, 670 -677.
AMA StyleJun-Jie Wang, Shiyuan Huang, Yu-Mian Wen, Yang Yang, Ming-Wei Liu. Experimental study on interaction between compressibility and permeability of a crushed sandstone–mudstone particle mixture. Marine Georesources & Geotechnology. 2016; 35 (5):670-677.
Chicago/Turabian StyleJun-Jie Wang; Shiyuan Huang; Yu-Mian Wen; Yang Yang; Ming-Wei Liu. 2016. "Experimental study on interaction between compressibility and permeability of a crushed sandstone–mudstone particle mixture." Marine Georesources & Geotechnology 35, no. 5: 670-677.