期刊文献+
共找到10篇文章
< 1 >
每页显示 20 50 100
Influence of repeated freeze-thaw on dynamic modulus and damping ratio properties of silty sand 被引量:3
1
作者 TianLiang Wang Chao Ma +1 位作者 Han Yan JianKun Liu 《Research in Cold and Arid Regions》 CSCD 2013年第5期572-576,共5页
Under repeated freezing and thawing in deep seasonal frozen regions, the stability and strength of the soil are imposed in the form of large uneven settlement, instability and strength reduction, which affect the norm... Under repeated freezing and thawing in deep seasonal frozen regions, the stability and strength of the soil are imposed in the form of large uneven settlement, instability and strength reduction, which affect the normal operation of railway lines. This study is to obtain the influencing rules of freeze-thaw on the dynamic properties (dynamic strain, confining pressure and compactness) of silty sand. Based on an amount of inner tests, the dynamic modulus and damping ratio properties of silty soil subjected to repeated freeze-thaw cycles were deeply researched and analyzed. The results are as follows: At the same dynamic strain, the relationship of dynamic stress and freeze-thaw cycles presents negative cor- relation, and the relationship of dynamic stress, confining pressure and compactness present positive correlation. The dynamic modulus double decreases while the damping ratio double increases with incremental increase in dynamic strain. The dynamic modulus sharply decreases while the damping ratio increases with incremental increase in freeze-thaw cycles, and then the changes level off after six freeze-thaw cycles. The dynamic modulus increases while the damping ratio decreases as the confining pressure and compactness increase at the same strain level. 展开更多
关键词 freeze-thaw cycles silty sand dynamic modulus damping ratio
下载PDF
Investigation on creep behavior of warm frozen silty sand under thermo-mechanical coupling loads 被引量:1
2
作者 ZHANG Feng SHI Sheng +1 位作者 FENG De-cheng CAI Lei-zhou 《Journal of Mountain Science》 SCIE CSCD 2021年第7期1951-1965,共15页
In cold regions,the creep characteristics of warm frozen silty sand have significant effect on the stability of slope and subgrade.To investigate the creep behavior of warm frozen silty sand under thermo-mechanical co... In cold regions,the creep characteristics of warm frozen silty sand have significant effect on the stability of slope and subgrade.To investigate the creep behavior of warm frozen silty sand under thermo-mechanical coupling loads,a series of triaxial creep tests were carried out under different temperatures and stresses.The test results reveal that the creep strains decrease as the consolidation stress increases,and finally tend to be equal under the same loading stress,regardless of whether the stress is isotropic or deviatoric.Additionally,warm frozen silty sand is highly sensitive to temperature,which greatly influences the creep strain both in the consolidation stage and loading stage.Furthermore,based on the creep test phenomena,a new creep model that considers the influence of the stress level,temperature,hardening,and damage effect was established and experimentally validated.Finally,the sensitivity of the model parameters was analyzed,and it was found that the creep curve transitions from the attenuation creep stage to the non-attenuation creep stage as the temperature coefficient and stress coefficient increases.The hardening effect gradually changes to the damage effect as the coupling coefficient of the hardening and damage increases. 展开更多
关键词 Creep behavior Warm frozen silty sand Constitutive model Hardening and damage
下载PDF
Migration process of ammonium ion in saturated silty sand and sandy loam
3
《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第4期29-34,共6页
MigrationprocesofammoniumioninsaturatedsiltysandandsandyloamZhuWanpeng,YangZhihua,JiangZhanpengDepartmentofE... MigrationprocesofammoniumioninsaturatedsiltysandandsandyloamZhuWanpeng,YangZhihua,JiangZhanpengDepartmentofEnvironmentalEngin... 展开更多
关键词 Migration process of ammonium ion in saturated silty sand and sandy loam
下载PDF
Interaction of the Mining Environment on the Properties of Hydraulic Mortars in Silty Sands in Togo
4
作者 Kossi Bollanigni Amey 《Open Journal of Civil Engineering》 2022年第1期1-13,共13页
The objective of this study is to determine the influence of the surrounding soils on the granular properties of the silty sands of Togo and on the resistance of the mortars. Sand compositions are made by substituting... The objective of this study is to determine the influence of the surrounding soils on the granular properties of the silty sands of Togo and on the resistance of the mortars. Sand compositions are made by substituting silty sands with clay soil, vegetal soil, lateritic soil or fine elements (<0.08 mm) which are the surrounding land polluting the sands in Togo. After identification tests, the mixtures were used to prepare test specimens of mortar which are subjected to bending and compression. It appears that additions of clay and plastic soils (ES = 0, VBM > 0.53 and IP > 19) from 10% to 35% cause drops in resistance of mortars from 7% to 96%;this loss is 8% to 70% for the rates of addition of less clayey soil (ES = 33, VBM = 0.40 and IP = 0) at rates of 10% to 100%. As for fine powdery soils (ES = 56.53 and VBM = 0.25), they have virtually no influence on resistance (loss of less than 3% for rates of 100%). Construction stakeholders thus have a decision-making tool for the choice of silty sand extraction zones according to the surrounding land and the quality of the desired concrete. 展开更多
关键词 MORTAR silty sand POLLUTANTS Physical and Mechanical Properties
下载PDF
Shear Resistance of Siltous Sands Improved with Bridelia Tannins
5
作者 Sinko Banakinao Soviwadan Drovou +1 位作者 Komlan Lolo Kodjo Attipou 《Geomaterials》 2024年第1期1-11,共11页
The ruin of several civil engineering works occurs due to shear rupture of the ground. When the stress is greater than the shear resistance, the internal friction angle and the cohesion of the soil loosen and rupture ... The ruin of several civil engineering works occurs due to shear rupture of the ground. When the stress is greater than the shear resistance, the internal friction angle and the cohesion of the soil loosen and rupture occurs. Cement and lime are often used to stabilize soils and improve soil strength. The costs and environmental problems of these technologies raise concerns and challenge researchers to innovate with clean, inexpensive materials, accessible to the most disadvantaged social classes. The question that this study seeks to answer is whether the binders derived from plant tannins, which also stabilize soils, improve the shear resistance of these soils. To do this, we determined for silty sand the shear parameters, notably the cohesion and the angle of internal friction in the non-stabilized state and when they are stabilized with the powder of the bark of the Bridelia under different water states. The results show that the addition of Bridelia powder to silty sand increases the cohesion of the soil by nearly 70.71% and the friction angle by 4.31%. But in unfavourable water conditions, the cohesion and internal friction angle of the silty sand material improved with Bridelia bark powder drops drastically by nearly 81.56%. but does not dissolve completely as for the same material. When it is not stabilized. This information is an invaluable contribution in the search for solutions to increase the durability of earthen constructions by improving the water-repellent properties of soils. 展开更多
关键词 silty sand Bridelia Tannins Shear Resistance COHESION Angle of Friction
下载PDF
Corrosion Performance of Carbon Steel in CO_(2) Aqueous Environment Containing Silty Sand with Different Sizes
6
作者 Songle Lu Wei Liu +3 位作者 Shian Zhang Xiaolong Qi Xiaogang Li Xuemin Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第11期1055-1066,共12页
Corrosion performance of carbon steel in CO2 aqueous environment containing silty sand with different sizes was investigated by immersion tests and electrochemical measurements. Silty sand could form an adsorption lay... Corrosion performance of carbon steel in CO2 aqueous environment containing silty sand with different sizes was investigated by immersion tests and electrochemical measurements. Silty sand could form an adsorption layer on steel surface in initial period, and the sand adsorption layer was turned into a mixture film of silty sand with corrosion product in last period. The adsorption layer in 325 mesh condition (large size) had the fewest pores for H2CO3 transport, exhibiting the highest cathodic current inhibition. In spite of little corrosion product, the sand adsorption film formed in 325 mesh condition induced the lowest corrosion rate. For 1000 and 5000 mesh silty sand, the sand adsorption layer had some pores for H2CO3 transport, leading to low cathodic current inhibition and much matrix dissolution. But the adsorption layer for 5000 mesh silty sand (small size) had the largest special surface area to accelerate heterogeneous precipitation of corrosion product FeCO3. Therefore, the mixture film in 5000 mesh condition was more compact, exhibiting stronger anodic inhibition and lower corrosion rate than those in 1000 mesh condition. 展开更多
关键词 silty sand sand adsorption layer Corrosion product film Corrosion inhibition Carbon steel
原文传递
Experimental Study on Suspended Sediment Concentration and Its Vertical Distribution under Spilling Breaking Wave Actions in Silty Coast 被引量:5
7
作者 夏云峰 徐华 +2 位作者 陈中 吴道文 张世钊 《China Ocean Engineering》 SCIE EI 2011年第4期565-575,共11页
In this paper, flume experiments are focused on sediment transport inside and outside the surf zone. According to the energy dissipation balance principle of sediment-laden flow and the similarity between energy dissi... In this paper, flume experiments are focused on sediment transport inside and outside the surf zone. According to the energy dissipation balance principle of sediment-laden flow and the similarity between energy dissipation of spilling breaking wave and hydraulic jump, formulas are proposed to predict time averaged suspended sediment concentration under both non-breaking and breaking waves. Assuming that the sediment diffusion coefficient, which is related with energy dissipation, is proportional to water depth, formulas are proposed to predict close-to-bed suspended sediment concentration and vertical distribution of suspended sediment under spilling breaking waves, and the prediction shows a good agreement with the measurement. 展开更多
关键词 silty sand breaking wave energy dissipation suspended sediment concentration vertical distribution
下载PDF
Intergrain contact density indices for granular mixes——Ⅰ: Framework 被引量:7
8
作者 S. Thevanayagam 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期123-134,共12页
Mechanical behavior such as stress-strain response, shear strength, resistance to liquefaction, modulus, and shear wave velocity of granular mixes containing coarse and fine grains is dependent on intergrain contact d... Mechanical behavior such as stress-strain response, shear strength, resistance to liquefaction, modulus, and shear wave velocity of granular mixes containing coarse and fine grains is dependent on intergrain contact density of the soil. The global void ratio e is a poor index of contact density for such soils. The contact density depends on void ratio, fine grain content (Cv), size disparity between particles, and gradation among other factors. A simple analysis of a two-sized particle system with large size disparity is used to develop an understanding of the effects of Cv, e, and gradation of coarse and fine grained soils in the soil mix on intergrain contact density. An equivalent intergranular void ratio (ec)oq is introduced as a useful intergrain contact density for soils at fines content of less than a threshold value Crth. Beyond this value, an equivalent interfine void ratio (ef)eq is introduced as a primary intergrain contact density index. At higher values of Cv beyond a limiting value of fine grains content CVL, an interfine void ratio ef is introduced as the primary contact density index. Relevant equivalent relative density indices (Drc)eq and (Drf)eq are also presented. Experimental data show that these new indices correlate well with steady state strength, liquefaction resistance, and shear wave velocities of sands, silty sands, sandy silts, and gravelly sand mixes. 展开更多
关键词 sand SILT silty sand sandy silt cyclic strength shear wave velocity intergrain contact density
下载PDF
Intergrain contact density indices for granular mixes——Ⅱ: Liquefaction resistance 被引量:3
9
作者 S. Thevanayagam 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期135-146,共12页
Whether the presence of non-plastic silt in a granular mix soil impact its liquefaction potential and how to evaluate liquefaction resistance of sand containing different amounts of silt contents are both controversia... Whether the presence of non-plastic silt in a granular mix soil impact its liquefaction potential and how to evaluate liquefaction resistance of sand containing different amounts of silt contents are both controversial issues. This paper presents the results of an experimental evaluation to address these issues. Two parameters, namely, equivalent intergranular void ratio (ec)eq and equivalent interfine void ratio (ef)eq, proposed in a companion paper (Thevanayagam, 2007) as indices of active grain contacts in a granular mix, are used to characterize liquefaction resistance of sands and silty sands. Results indicate that, at the same global void ratio (e), liquefaction resistance of silty sand decreases with an increase in fines content (Cv) up to a threshold value (Crth). This is due to a reduction in intergrain contact density between the coarse grains. Beyond Crth, with further addition of fines, the interfine contacts become significant while the inter-coarse grain contacts diminish and coarse grains become dispersed. At the same e, the liquefaction resistance increases and the soil becomes stronger with a fttrther increase in silt content. Beyond a limiting fines content (CrL), the liquefaction resistance is controlled by interfine contacts only. When Cr〈Crth, at the same (e)eq, the liquefaction resistance of silty sand is comparable to that of the host clean sand at a void ratio equal to (ec)eq. When CF〉CFth, at the same (ef)eq, the cyclic strength of a sandy silt is comparable to the host silt at a void ratio equal to (ef)eq. 展开更多
关键词 sand SILT FINES silty sand LIQUEFACTION cyclic strength
下载PDF
A multi-attribute decision making approach of mix design based on experimental soil characterization 被引量:1
10
作者 Amit K. BERA Tanmoy MUKHOPADHYAY +1 位作者 Ponnada J.MOHAN Tushar K. DEY 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2018年第3期361-371,共11页
The clay mineral composition is one of the major factors that governs the physical properties of silty sand subgrade. Therefore, a thorough knowledge of mineral composition is essential to predict the optimum engineer... The clay mineral composition is one of the major factors that governs the physical properties of silty sand subgrade. Therefore, a thorough knowledge of mineral composition is essential to predict the optimum engineering properties of the soil, which is generally characterized by different indices like maximum dry density (MDD), California bearing ratio (CBR), unconfined compressive strength (UCS) and free swelling index (FSI). In this article, a novel multi- attribute decision making (MADM) based approach of mix design has been proposed for silty sand- artificial clay mix to improve the characteristic strength of a soil subgrade. Experimental investigation has been carried out in this study to illustrate the proposed approach of selecting appropriate proportion for the soil mix to optimize all the above mentioned engineering properties simultaneously. The results show that a mix proportion containing approximately 90% silty sand plus 10% bentonite soil is the optimal combination in context to the present study. The proposed methodology for optimal decision making to choose appropriate combination of bentonite and silty sand is general in nature and therefore, it can be extended to other problems of selecting mineral compositions. 展开更多
关键词 silty sand bentonite soil soil mix design multi-attribute decision making
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部