scholarly journals Rheological Behavior and Modeling of a Crushed Sandstone-Mudstone Particle Mixture

Processes ◽  
2018 ◽  
Vol 6 (10) ◽  
pp. 192 ◽  
Author(s):  
Zhenfeng Qiu ◽  
Ting Cao ◽  
Yongsuo Li ◽  
Junjie Wang ◽  
Yulong Chen
Keyword(s):  
Strain Curve ◽  
Coarse Grained ◽  
Cohesive Soils ◽  
Filling Material ◽  
Compression Tests ◽  
Rock Fill ◽  
Particle Mixture ◽  
Engineering Projects ◽  
Coarse Grained Soil

A mixture of sandstone and mudstone particles is often used as the main filling material for many agriculture-related and civil engineering projects, including rock-fill dams and foundations. The long-term rheological deformation experienced by rock-fill dams and foundations filled with this mixture is much bigger than that of coarse-grained and cohesive soils, due to the deterioration and softening of the mudstone particles. This study focuses on the rheological deformation of a sandstone-mudstone particle mixture, prepared by mixing sandstone and mudstone particles, based on the content by weight of four mudstone particle types. Confined uniaxial compression tests were performed to test the rheological deformation of 24 samples of the mixture, and a stress-strain curve was obtained for each test. On the basis of compression curves, the rheological process of the mixture was divided into four phases: linear, attenuation rheological, secondary attenuation rheological and stable phases. The three defining features of the curve, namely the rheological attenuation factors, attenuation rheology critical strain and limited rheological strain, were then determined and modeled. A segmented rheological model was then proposed, based on a modified attenuation rheological constitutive model for coarse-grained soil. The modelled results compared well with the experimental data, and the modelled compression-curve prediction was able to describe the two-stage attenuation rheology features (attenuation rheological and secondary attenuation rheological phases) of the sandstone-mudstone particle mixture.

Study on Test of the Influence of Moisture Content on Creep Property of Sandy Slate Coarse-Grained Soil

2013 ◽  
Vol 405-408 ◽  
pp. 1733-1738 ◽  
Author(s):  
Qun Liu ◽  
Xiang Wang ◽  
Xiao Dong Song
Keyword(s):  
Moisture Content ◽  
Creep Test ◽  
Creep Property ◽  
Coarse Grained ◽  
Creep Model ◽  
Moisture Contents ◽  
Compression Creep ◽  
Moisture Conditions ◽  
Coarse Grained Soil

Coarse-grained soil is widely used in subgrade engineering, creep property of which is the important factor that affects long-term settlement of fill embankment. The creep property of sandy slate coarse-grained soil under different moisture conditions is analyzed through uniaxial compression creep test on influence rule of moisture content on creep of coarse-grained soil. Relations between moisture contents and creep parameters are studied on the basis of H-K Creep Model. It turns out that moisture content is the important factor that affects creep property of sandy slate coarse-grained soil and using dry or saturated coarse-grained soil is able to decrease long-term settlement of embankment.

scholarly journals An Improved Large-Scale Stress-Controlled Apparatus for Long-Term Seepage Study of Coarse-Grained Cohesive Soils

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6280
Author(s):  
Chenghao Chen ◽  
Shengshui Chen ◽  
Shiang Mei ◽  
Shaoyang Han ◽  
Xian Zhang ◽  
...  
Keyword(s):  
Stress Relaxation ◽  
Large Scale ◽  
Coarse Grained ◽  
Core Material ◽  
Marginal Effect ◽  
Cohesive Soils ◽  
Pressurized Water ◽  
Water Provision ◽  
Constant Head

Clay–gravel mixture has been widely used in high embankment dams and understanding its seepage characteristics is critical to dam safety. From the instrumental perspective, the realization of continuous pressurized water supply becomes a key technical challenge, significantly restricting the working conditions replicated in previous seepage apparatuses. To this end, a novel water provision system, relying on parallel-disposed sensor-based pressure devices, was introduced, so that the application of an existing large-scale stress-controlled apparatus can be expanded to long-term seepage tests regarding coarse-grained cohesive soils. Constant-head permeability tests were conducted on original-graded clay–gravel mixtures to investigate their hydraulic properties, incorporating the influence of stress relaxation. Test results show that with 35% gravel content, the clay–gravel mixture is suitable for dam construction as the core material. The stress relaxation holds a marginal effect on the hydraulic conductivity of soil. The functionality of this improved apparatus is verified, especially under long-term seepage conditions.

Test Study of Influence of Fine Particle Content on Creep Property of Sandy Slate Coarse-Grained Soil

2013 ◽  
Vol 438-439 ◽  
pp. 1372-1375
Author(s):  
Li Hao Jia ◽  
Xiang Bo Deng ◽  
Man Jiang
Keyword(s):  
Fine Particle ◽  
Creep Property ◽  
Coarse Grained ◽  
Creep Model ◽  
Grain Composition ◽  
Particle Content ◽  
Fine Grain ◽  
Test Study ◽  
Coarse Grained Soil

Creep property of coarse-grained soil is an important property influencing long-term settlement of embankment. Based on the H-K creep model which is consistent with the experimental results and verified by uniaxial compression creep test, relationship between fine grain composition and creep parameter and pattern of creep property of sandy slate coarse-grained soil influenced by fine grain composition are studied. It turns out that fine particle content is the important factor that affects creep property of sandy slate coarse-grained soil and using fine particle content of 30% is able to decrease long-term settlement of embankment.

scholarly journals An Analysis of the Mechanical Characteristics and Constitutive Relation of Cemented Mercury Slag

2017 ◽  
Vol 2017 ◽  
pp. 1-14
Author(s):  
Xinwei Li ◽  
Sui Zhang ◽  
E-chuan Yan ◽  
Duoyou Shu ◽  
Yangbing Cao ◽  
...  
Keyword(s):  
Triaxial Compression ◽  
Failure Process ◽  
Guizhou Province ◽  
Coarse Grained ◽  
Uniaxial Compression Test ◽  
Compression Tests ◽  
Slag Structure ◽  
Triaxial Compression Tests ◽  
Chang Model ◽  
Coarse Grained Soil

This study focuses on mercury slag in the Tongren area of Guizhou Province, China. Computed tomography (CT) is used with uniaxial and triaxial compression tests to examine the mechanical changes in cemented mercury slag and its formation. The CT results for the uniaxial compression test reveal the overall failure process of the mercury slag structure. Based on the coarse-grained soil triaxial test, a modified Duncan-Chang model is compared with the actual monitoring results and is found to be suitable for the analysis of the slag constitutive model.

scholarly journals Shaping Microstructure and Mechanical Properties of High-Carbon Bainitic Steel in Hot-Rolling and Long-Term Low-Temperature Annealing

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 384
Author(s):  
Tomasz Dembiczak ◽  
Marcin Knapiński
Keyword(s):  
Mathematical Models ◽  
Hot Rolling ◽  
Constitutive Equations ◽  
Rolling Process ◽  
Bainitic Steel ◽  
Compression Tests ◽  
High Carbon ◽  
Bainite Steel ◽  
Dilatometric Studies

Based on the research results, coefficients in constitutive equations, describing the kinetics of dynamic, meta-dynamic, and static recrystallization in high-carbon bainitic steel during hot deformation were determined. The developed mathematical model takes into account the dependence of the changing kinetics in the structural size of the preliminary austenite grains, the value of strain, strain rate, temperature, and time. Physical simulations were carried out on rectangular specimens. Compression tests with a flat state of deformation were carried out using a Gleeble 3800. Based on dilatometric studies, coefficients were determined in constitutive equations, describing the grain growth of the austenite of high-carbon bainite steel under isothermal annealing conditions. The aim of the research was to verify the developed mathematical models in semi-industrial conditions during the hot-rolling process of high-carbon bainite steel. Analysis of the semi-industrial studies of the hot-rolling and long-term annealing process confirmed the correctness of the predicted mathematical models describing the microstructure evolution.

scholarly journals Long-term assessment of a modified tibial tuberosity advancement technique in dogs

2018 ◽  
Vol 70 (4) ◽  
pp. 1053-1059 ◽  
Author(s):  
R.M. Medeiros ◽  
M.A.M. Silva ◽  
P.P.M. Teixeira ◽  
D.G. Chung ◽  
M.E.B.A.M. Conceição ◽  
...  
Keyword(s):  
Gait Analysis ◽  
Positive Response ◽  
Tibial Tuberosity ◽  
Compression Tests ◽  
Radiographic Evidence ◽  
Long Term Follow Up

ABSTRACT The purpose of study was to assess long-term clinical and radiographic aspects of dogs’ stifle joints which had undergone a modified tibial tuberosity advancement technique (mTTA). A total of 15 stifles that had undergone mTTA for CCL disease of 11 patients were included in this study. Assessments involved patient’s gait analysis, cranial drawer and tibial compression tests, stifle goniometry range of articular motion, thigh and leg girth and radiographic evidence of progression of osteoarthrosis. Variables were compared between operated and healthy limbs and among moments (M0) on the early postop; (M1) 120 days postop; and (M2) approximately 5 years following surgery. A questionnaire regarding owner’s perceptions after approximately 5 years of surgery was assessed. Most dogs presented positive response to cranial drawer and tibial compression tests on operated knees. There was also decrease on goniometry and thigh girth and increase in leg girth. Radiographic evidence of progression of osteoarthritis was seen especially on the long-term follow-up (M2). On gait analysis, most animals presented some degree of lameness in different conditions, in contrast to owners’ perceptions. Osteoarthritis still develops in dogs following mTTA surgery for CCL disease. However, owners were overall satisfied with their recovery and would be willing to accept indication of mTTA for dogs with ruptured CCL.

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