Dynamic Response And Characteristics Of Tapered Rigid Core Composite Cement- Soil Piles Under Cyclic Loading,
2023
College of Civil Engineering, Hunan University of Technology, Zhuzhou, Hunan 412007, China
Dynamic Response And Characteristics Of Tapered Rigid Core Composite Cement- Soil Piles Under Cyclic Loading, Jie He, Duan-Wei Guo, De-Xin Song, Meng-Xin Liu, Lei Zhang, Qi-Feng Wen
Rock and Soil Mechanics
Tapered rigid core composite cement-soil pile is an emerging type of composite pile. In order to investigate its bearing behavior in engineering applications such as highways and railways under long-term cyclic loading, model tests were conducted on four composite piles with different pile core wedge angles, static loading ratios and cyclic loading ratios. The ultimate bearing capacity under static loading as well as the cumulative settlement, pile axial force distribution, tip resistance and side friction resistance were evaluated. The results indicated that the bearing capacity of tapered inner core composite piles under static loading was better than that of constant …
Infiltration Characteristics And Deformation Mechanism Of Rainfall-Induced Landslides In Three Gorges Reservoir Area Based On 1d And 2d Model Tests,
2023
Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, Ministry of Education, China Three Gorges University, Yichang, Hubei 443002, China,
College of Civil Engineering & Architecture, China Three Gorges University, Yichang, Hubei 443002, China,
Badong National Observation and Research Station of Geohazards, China University of Geosciences, Wuhan, Hubei 430074, China
Infiltration Characteristics And Deformation Mechanism Of Rainfall-Induced Landslides In Three Gorges Reservoir Area Based On 1d And 2d Model Tests, Li Wang, Fang-Yun Nan, Shi-Mei Wangi, Yong Chen, Xiao-Wei Li, Zhi-Hong Fan, Yu-Shan Chen
Rock and Soil Mechanics
Shallow deformation of ancient landslides induced by heavy rainfall is the most serious geological disaster in China's Three Gorges Reservoir Area (TGRA). It is important to explore the infiltration characteristics and its shallow deformation mechanism caused by heavy rainfall. In this study, the rainfall-induced landslide of the TGRA was selected as the research object, and the distributions of the soil permeability coefficients for rainfall-type landslide were summarized. Considering the effects of heavy rainfall, one-dimensional (1D) soil column infiltration test and two-dimensional (2D) landslide model test were conducted to study the infiltration characteristics of landslide soil and the corresponding shallow deformation …
Mechanical Properties Of Fractured Sandstone After Cyclic Thermal Shock,
2023
Key Laboratory of New Technology for Construction of Cities in Mountain Area, Ministry of Education, Chongqing University, Chongqing, 400045, China,
School of Civil Engineering, Chongqing University, Chongqing, 400045, China
Mechanical Properties Of Fractured Sandstone After Cyclic Thermal Shock, Man Li, Xian-Shan Liu, Yu-Hua Pan, Shi-Hao Qiao, Zi-Yu Hao, Lei Qian, Xiao-Lei Luo
Rock and Soil Mechanics
The stimulation of thermal reservoirs in sandstone and its long-term stability evaluation are of great significance to the development of geothermal energy. In this paper, the mechanical properties of fractured sandstone under 0–8 cycles of thermal shocks are studied. The experimental results show that the P-wave velocity, uniaxial compressive strength (UCS) and elastic modulus of fractured sandstone all decrease gradually with the increase in the number of thermal shocks under two types of cooling methods. Compared with the cooling method in the water, the natural cooling method in the air causes less damage to the mechanical properties of fractured sandstone. …
Evolution Mechanism Of Deformation And Failure Of Rock Slope With Controlling Fissure Through Transparent Physical Model Experiments,
2023
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China,
University of Chinese Academy of Sciences, Beijing 100049, China
Evolution Mechanism Of Deformation And Failure Of Rock Slope With Controlling Fissure Through Transparent Physical Model Experiments, Xian-Lun Leng, Chuan Wang, Qian Sheng, Wen-Jun Song, Jian Chen, Zhan-Rong Zhang, Fei Chen
Rock and Soil Mechanics
The deformation and failure evolution process of rock slope during disaster incubation period is controlled by internal long fissures (controlling fissures), and the evolution mechanism is of great significance for the prevention of landslide disasters. Based on the transparent physical model experiment technology, two typical rock slopes with controlling fissures (one with a steep fissure in the upper part of slope and the other with a gently inclined fissure in the lower part) were selected as the objects, and the evolution process of deformation and failure inside the slopes was studied through physical model experiments using the self-developed equipment. The …
Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer,
2023
Clemson University
Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer, Riley Blais
All Theses
Pumping tests with sinusoidal variation in pumping rate have been proposed as a method for improving aquifer characterization. These tests can interrogate a larger aquifer volume than slug tests and they can be more sensitive to small variations in drawdown. Current methods of using sinusoidal variations of rate are based on measuring pressure signals from the reservoir or aquifer, which requires access to monitoring wells. An alternative approach has been developed that measures the strain in the vadose zone instead of pressure in the reservoir. An instrument has been developed at Clemson University that can measure small strains using optical …
Understanding The Hydromechanical Effects Of Extreme Events To Improve The Performance Of Infrastructure Foundations,
2023
Clemson University
Understanding The Hydromechanical Effects Of Extreme Events To Improve The Performance Of Infrastructure Foundations, Siddharth Marathe
All Dissertations
Extreme hydroclimatic events like heavy rainfall, flooding, and prolonged drought can potentially cause the failure of infrastructure foundations, leading to socio-economic losses. The objective of this dissertation is to understand the deformation and bearing capacity behavior of drilled shafts subjected to extreme hydroclimatic events, including heavy rainfall, prolonged drought, and earthquake. The Finite Element Method (FEM) results show that during rainfall, the drilled shaft settled caused by a decrease in the porewater pressure in the sand leading to a decrease in the axial bearing capacity. The axial force variation from an experimental investigation showed good agreement with the FEM. The …
Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling,
2023
Clemson University
Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling, Kaleb Boland
All Theses
This study was inspired by a tree’s reliance on its root system that enables it to withstand a natural disaster, such as an extreme hydroclimatic event or hurricane. This curiosity has led to an investigation into what makes this possible, developing a new and innovative foundation configuration for infrastructure systems, and a new possible construction material and method. This study provides results on a material that does not have conventional testing procedures or standards: a tree root. The trees studied are common to the upstate of South Carolina, which are Pine, Sweetgum, and White Oak. According to the results, on …
Permeability Evolution In The Initial Period Of Oil Production Based On Field Well Test Data And Coreflooding Tests,
2023
Department of Oil and Gas Technologies, Perm National Research Polytechnic University, 614990 Perm, Russia
Permeability Evolution In The Initial Period Of Oil Production Based On Field Well Test Data And Coreflooding Tests, Kozhevnikov Evgenii V., Turbakov Mikhail S., Riabokon Evgenii P., Gladkikh Evgeniy A., Poplygin Vladimir V., Guzev Mikhail A., Cheng-Zhi Qi
Rock and Soil Mechanics
Permeability prediction during hydrocarbon production is a rather important problem. The decrease in permeability due to depletion reserves and the drop in reservoir pressure (increase in effective pressure) leads to an increase in the time of oil or gas production. A large number of works have been devoted to the problem of permeability reduction due to effective pressure. Establishment of permeability models is carried out by various methods including coreflooding tests and field well tests. The results of previous studies have shown that permeability has a power-law or exponential dependence on effective pressure, however, the difficulty in predicting permeability is …
Long-Term Deformation Test And Model Study Of One-Dimensional Consolidation Of South China Sea Coral Mud Under Graded Loading And Unloading,
2023
Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education, Hohai University, Nanjing, Jiangsu 210098, China
Long-Term Deformation Test And Model Study Of One-Dimensional Consolidation Of South China Sea Coral Mud Under Graded Loading And Unloading, Yang Shen, Jue Deng, He Weng, Long Yang
Rock and Soil Mechanics
South China Sea coral mud is a calcareous ooze of marine rock and soil formed by the accumulation of bones and debris after the death of coral groups, which has special engineering properties. It is significant to investigate its time dependent long-term nonlinear deformation under load for the construction and long-term stability analysis of dredger fill islands and reefs. Three groups of one-dimensional consolidation compression tests of coral mud with different loading and unloading schemes were carried out, and the influence of stress history on its long-term deformation properties was explored by changing the loading time and loading-unloading loops. According …
Effect Of Rubber–Sand Mixture Gradation On Shear Characteristics Of Mixed Soil,
2023
School of Mechanics and Engineering Science, Shanghai University, Shanghai 200444, China
Effect Of Rubber–Sand Mixture Gradation On Shear Characteristics Of Mixed Soil, Fei-Yu Liu, Hao-Ze Li, Jun Fu, Hong-Lei Sun
Rock and Soil Mechanics
To study the shear characteristics of rubber–sand mixtures, the effects of four rubber–sand mixture gradations (one type of gap gradation, two types of continuous gradations, and one type of open gradation), three rubber contents (10%, 30%, and 60%), and three vertical stresses (30 kPa, 60 kPa, and 90 kPa) on the strength and volumetric change characteristics of rubber–sand mixtures were investigated by using a large-scale laboratory direct shear apparatus. Then, the discrete element models of pure sand and rubber–sand mixtures were established according to the same gradation and rubber content. The intrinsic mechanism of rubber–sand mixtures was explored from the …
Deformation And Load Transmission Mechanism Of Prestressed Reinforced Embankment Subjected To Rockfall Impacts,
2023
School of Civil Engineering, Chongqing University, Chongqing 400045, China,
Department of Architectural & Engineering, Chongqing Industry Polytechnic College, Chongqing 401120, China
Deformation And Load Transmission Mechanism Of Prestressed Reinforced Embankment Subjected To Rockfall Impacts, Shu-Wen Ma, Liang Lu, Zong-Jian Wang, Jing-Tian Wang, Lan-Xing Li
Rock and Soil Mechanics
The prestressed reinforced soil structure was proposed to solve the problem of large-area depressions of soil highways under rockfall impacts in remote mountain areas. Comparative model tests for prestressed reinforced soil embankment and traditional soil embankment were conducted to explore the deformation performance, mechanical response, and load transmission mechanism of both embankments under rockfall impacts. The results show that the size of pits formed in prestressed reinforced soil embankment is significantly smaller than that in traditional soil embankment, which reflects the good impact deformation resistance of prestressed reinforced soil embankment. The embankment stiffness increases with the increase of impact times, …
Excavation Response Analysis Of Prefabricated Recyclable Support Structure For Water-Rich Silt Foundation Pit,
2023
School of Civil Engineering, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,
Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong 519080, China,
Guangdong research center for underground space exploitation technology, Guangzhou, Guangdong 510275, China
Excavation Response Analysis Of Prefabricated Recyclable Support Structure For Water-Rich Silt Foundation Pit, Rui-Song Wang, Cheng-Chao Guo, Pei-Yuan Lin, Fu-Ming Wang
Rock and Soil Mechanics
The prefabricated recyclable support structure provides a new green support system with economic security, functional coordination and sustainable development for the development of underground space. The physical model test of the foundation pit of a pipe-jacking working well in Zhengzhou city is carried out based on the similarity theory. A three-dimensional fluid-solid coupling model that can differentiate the deformation difference between rigid and flexible components in the support system is established by using the ABAQUS software. The stress and deformation characteristics of support structure in the process of dewatering and excavation are analyzed. The influences of dewatering and excavation on …
Stress Jumping Of Elastic-Brittle Circular Coal Roadway And Prediction Model Of Rock Burst,
2023
China National Coal Group Corporation, Beijing 100120, China
Stress Jumping Of Elastic-Brittle Circular Coal Roadway And Prediction Model Of Rock Burst, Shu-Wen Wang, Wen-Jun Ju, Chun-Hui Zhang, Shi-Jie Su, Chuang Lu
Rock and Soil Mechanics
In order to predict the rock burst disasters of coal roadway, the coal with bump tendency is regarded as a perfectly elastic-brittle material, and the mechanical model of circular coal roadway is established to analyze the distribution characteristics of stress and deformation energy density of surrounding rock of coal roadway, and then the rock burst prediction model of coal roadway is established to predict the rock burst disaster of coal roadway. The results show that the tangential stress and deformation energy density of the surrounding rock of elastic-brittle coal roadway jump at the interface between the elastic zone and the …
Loosening Earth Pressure Based On Triangular Slip Surfaces,
2023
College of Civil and Architectural Engineering, Guangxi University of Science and Technology, Liuzhou, Guangxi 545006, China,
Guangxi Zhuang Autonomous Region Engineering Research Center of Geotechnical Disaster and Ecological Control, Liuzhou, Guangxi 545006, China
Loosening Earth Pressure Based On Triangular Slip Surfaces, Jia-Quan Wang, Jia-Ming Chen, Zhi-Nan Lin, Yi Tang
Rock and Soil Mechanics
Soil deformation caused by karst collapse and tunnel excavation often causes uneven settlement, ground collapse and cracking in foundation. Development of approaches to determine the distribution of loose earth pressure at the top of soil structure and analyze the relationship between soil deformation and soil arching effect accurately is of much importance. A series of classical trapdoor tests with different H/B ratios is conducted to reveal the variation law of soil deformation and settlement on the loose earth pressure at the top of the structure. Based on the test results, a mathematical model is proposed to analyze the loose earth …
Study On The Mechanism Of Coal Bursts Induced By Quasi-Resonance Of Roof-Support System,
2023
School of Mechanics and Engineering, Liaoning Technical University, Fuxin, Liaoning 123000, China
Study On The Mechanism Of Coal Bursts Induced By Quasi-Resonance Of Roof-Support System, Kai-Xing Wang, Jia-Qi Xue, Yi-Shan Pan, Lin-Ming Dou, Yong-Hui Xiao
Rock and Soil Mechanics
The mechanism and prevention of coal burst is an important issue in the study of coal mine dynamic disasters. The disturbance of surrounding rocks can trigger the quasi-resonance phenomena of roadway roof support system in close proximity to its resonant state, ultimately inducing impact disasters. This is manifested in three strong quasi-resonant responses, including roof displacement, velocity and acceleration. Based on the support instability and plastic buckling criteria, three safety factors and the corresponding dangerous disturbance frequency ratio interval for the dynamic failure of support are proposed, and the support damping control strategy is given, aiming at the impact disasters …
Centrifugal Experimental Study On Seismic Response Of Bridge Pile Group Foundation In Saturated Sand Field Overlain By Water,
2023
College of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China
Centrifugal Experimental Study On Seismic Response Of Bridge Pile Group Foundation In Saturated Sand Field Overlain By Water, Zhi-Xiao Yan, Yu-Run Li, Dong-Sheng Wang, Yong-Zhi Wang
Rock and Soil Mechanics
In order to explore the dynamic interaction of the soil−pile group foundation−bridge structure system in saturated sand field overlain by water, a physical similarity model of the vertical (inclined) pile group foundation−bridge structure was designed and manufactured. Centrifuge shaking table tests with seismic wave inputs of different ground motion intensities and characteristics were conducted. The dynamic characteristic indices of pile group foundation−bridge structure were analyzed, and the development of excess pore water pressure in the saturated sand foundation overlain by water and the dynamic response of pile−soil interaction were also investigated. The results indicated that the presence of overlying water …
Relationship Between Macro And Micro Friction Coefficients Of Sandstone Structural Surface Based On Nano-Scratch Test,
2023
School of Civil Engineering, Shaoxing University, Shaoxing, Zhejiang 312000, China
Relationship Between Macro And Micro Friction Coefficients Of Sandstone Structural Surface Based On Nano-Scratch Test, Shuang Zheng, Rui Yong, Shi-Gui Du, Zhi-Hai He, Zhen Zhong, Ying-Ying Zhang, Su-Gang Sui
Rock and Soil Mechanics
Basic friction coefficients are important parameters affecting the shear strength of structural surface in rock masses. The basic friction coefficient determined by conventional laboratory test methods is influenced by mineral composition, temperature, and other factors. To systematically reveal the basic frictional properties of structural surfaces, the macro and micro friction coefficients of sandstone were investigated separately, and their relationship was established. First, mineral components and mechanical parameters of the sandstone were determined by X-ray diffraction and nanoindentation tests. Second, the friction coefficient in the macro scale was examined by tilt test and direct shear test, and the direct shear test …
Numerical Study On Failure Path Of Rock Slope Induced By Multi-Stage Excavation Unloading Based On Crack Propagation,
2023
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China,
University of Chinese Academy of Sciences, Beijing 100049, China
Numerical Study On Failure Path Of Rock Slope Induced By Multi-Stage Excavation Unloading Based On Crack Propagation, Chuan Wang, Xian-Lun Leng, Zhan-Rong Zhang, Chuang Yang, Jian Chen
Rock and Soil Mechanics
The investigation on failure patterns and paths of cracked rock slopes under excavation unloading is one of the hot issues in the slope engineering field. Accurate identification of the potential failure path is of great significance for excavation safety and support design of the slope. A theoretical method for crack propagation discrimination was embedded into the numerical simulation based on the fracture propagation analysis method, and the quick simulation of initiation, propagation, and coalescence of discontinuous cracks in rock masses was realized through stress intensity factor calculation at crack tip, crack propagation pattern recognition, crack initiation angle derivation, and crack …
An Improved Shear Strength Model Of Unsaturated Soils Over A Wide Suction Range,
2023
Key Laboratory of Urban Underground Engineering of Ministry of Education, Beijing Jiaotong University, Beijing 100044, China
An Improved Shear Strength Model Of Unsaturated Soils Over A Wide Suction Range, Yu-Xin Zhao, Xu Li, Sen Lin, Xiao-Meng Wang
Rock and Soil Mechanics
Different types of unsaturated soils are widespread in nature. Due to the differences in grain size and mineral composition, the shear strength characteristics of the unsaturated soils are significantly different over a wide suction range. In order to establish a unified model for predicting the shear strength of different soil types over a wide suction range, a systematic investigation was carried out to examine the effect of soil type on the shear strength of unsaturated soils. An improved shear strength model is proposed based on the advantages of two traditional equations. The proposed model is verified by comparing the published …
Effects Of Cut Depth And Cut Spacing On A Conical Pick In Rock Cutting,
2023
School of Resources and Safety Engineering, Central South University, Changsha, Hunan 410083, China
Effects Of Cut Depth And Cut Spacing On A Conical Pick In Rock Cutting, Jiu-Bo Liao, Xi-Bing Li, Shao-Feng Wang, Kun Du
Rock and Soil Mechanics
In order to study the effects of different cut depths and cut spacings on cutting force and specific cutting energy acting on a conical pick, the laboratory linear rock cutting tests were carried out on carbonaceous slate and rhyolite clastic rock based on the TRW-300 true triaxial electro-hydraulic servo system and self-designed innovative pick loading platform. Experimental results indicate that there were four types of failure modes on a conical pick in rock cutting, and there was a synergistic effect between two adjacent picks. The mean cutting force linearly increases with the increasing cut depth and cut spacing. The specific …
