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A statistical reappraisal of the relationship between liquid limit and specific surface area, cation exchange capacity and activity of clays 被引量:1
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作者 Giovanni Spagnoli Satoru Shimobe 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2019年第4期874-881,共8页
More than 500 datasets from the literature have been used to evaluate the relationships of specific surface area (SSA),cation exchange capacity (CEC) and activity versus the liquid limit (LL).The correlations gave R^2... More than 500 datasets from the literature have been used to evaluate the relationships of specific surface area (SSA),cation exchange capacity (CEC) and activity versus the liquid limit (LL).The correlations gave R^2 values ranging between 0.71 and 0.92.Independent data were also used to validate the correlations.Estimated SSA values slightly overestimate the measured SSA up to 100 m^2/g.Regarding the estimated CEC values,they overestimated the measured CEC values up to 20 meq/(100 g).A probabilistic approach was performed for the correlations of SSA,CEC and activity versus LL.The analysis shows that the relations of SSA,CEC and activity with LL are robust.Using the LL values,it is possible to assess other basic engineering properties of clays. 展开更多
关键词 liquid limit(LL) Specific surface area(SSA) Cation exchange capacity(CEC) ACTIVITY statistical analysis
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Influence of heating and water-exposure on the liquid limits of GMZ01 and MX80 bentonites
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作者 Yuemiao Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第2期188-192,共5页
Bentonite has been considered as a buffer material for embedding canisters with high-level radioactive waste(HLW) in deep geological repositories.GMZ bentonite deposit,located in Xinghe County,Inner Mongolia Autonom... Bentonite has been considered as a buffer material for embedding canisters with high-level radioactive waste(HLW) in deep geological repositories.GMZ bentonite deposit,located in Xinghe County,Inner Mongolia Autonomous Region,China was proposed as a buffer/backfill material for HLW repository in China.The liquid limits of natural Na-bentonite GMZ01 and commercial Na-bentonite MX80,which are previously heated at 80 ℃ and 95 ℃,respectively,and exposed to water for different times are measured.It is observed that the liquid limit of GMZ01 increases slightly at the beginning,and then decreases as the heating time increases,while the liquid limit of MX80 decreases with the heating time.The liquid limits of both GMZ01 and MX80 decrease with increasing water-exposure time.After the samples are heated at 80℃and 95 ℃ for several months,the mineralogical composition of GMZ01 does not exhibit evident change,whereas MX80 experiences some changes.In addition,the chemical composition,cation exchange capacity(CEC) and exchangeable cation of all the samples do not change significantly. 展开更多
关键词 high-level radioactive waste(HLW) deep geological disposal BENTONITE HEATING water-exposure liquid limit
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Test study of high liquid limit clay modified by quick lime used as sub-grade material 被引量:3
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作者 张文慧 席文勇 +1 位作者 王保田 洪宝宁 《Journal of Central South University》 SCIE EI CAS 2008年第S2期126-130,共5页
Through laboratory test, the relationships among change of compactibility, liquid/plastic limit, free swell, swell ratio without load, california bearing ratio (CBR) and soakage (after being soaked in water), and mix-... Through laboratory test, the relationships among change of compactibility, liquid/plastic limit, free swell, swell ratio without load, california bearing ratio (CBR) and soakage (after being soaked in water), and mix-ratio of quick lime and time were studied. The results show that optimum water content, plastic limit and CBR of high liquid limit clay improved by quick lime increase with the increase of mix-ratio of quick lime, while the maximum dry density, liquid limit, plasticity index, soakage (after being immersed in water), free swell, and swell ratio without load decrease with the increase of mix-ratio of quick lime. Plastic limit of high liquid clay improved by quick lime gradually increases with time, while the liquid limit, plasticity index, free swell and swell ratio without load gradually decrease with time. When the mix-ratio of quick lime exceeds 2%, after 14 d, swell ratio without load of the improved clay is zero, its free swell is about 30% of that of untreated soil, and its plasticity index is less than 26 for sub-grade material, satisfying the requirement by 'Specifications for Design of Highway Subgrade'. 展开更多
关键词 high liquid limit CLAY quick LIME PLASTICITY index california bearing ratio (CBR) soakage EXPANSIBILITY
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Influence of Heating and Water Exposure on Liquid Limit of Bentonite
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作者 Yuemiao Liu Beijing Research Institute of Uranium Geology,Beijing 100029,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期187-187,共1页
Bentonite has been considered as the buffer material for embedding canisters with high-level radioactive waste(HLW)in the deep geology repositories. GMZ bentonite deposit which is located in Xinghe County,Inner Mongol... Bentonite has been considered as the buffer material for embedding canisters with high-level radioactive waste(HLW)in the deep geology repositories. GMZ bentonite deposit which is located in Xinghe County,Inner Mongolia has been proposed as buffer/backfill material for HLW repository in China. Liquid limit of natural Na-bentonite GMZ01 and commercial Na-bentonite MX80 which were previously put in the oven at 80℃and 95℃,and exposed to water for different times were measured.The liquid limit of GMZ01 increased slightly at the beginning, and then decreased as the heating time increased. 展开更多
关键词 HIGH-LEVEL RADIOACTIVE waste deep GEOLOGICAL DISPOSAL BENTONITE liquid limit
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Investigation on the Arc Ignition Characteristics and Energy Absorption of Liquid Metal Current Limiter Based on Self-Pinch Effect 被引量:3
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作者 琚兴宝 孙海顺 +1 位作者 杨倬 张俊民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期531-537,共7页
The GaInSn liquid metal current limiter based on the fluid pinch effect has broad application prospects due to its particular properties. However, the limited rated current and abil- ity of power dissipation are the c... The GaInSn liquid metal current limiter based on the fluid pinch effect has broad application prospects due to its particular properties. However, the limited rated current and abil- ity of power dissipation are the critical problems for its wide application. Firstly, the temperature distribution of the liquid metal current limiter (LMCL) was obtained by experiments with a rated current of 1 kA and the arc ignition phenomenon was observed with 1.5 kA, which indicates that the rated current is mainly limited by the arc rather than the high temperature compared to the traditional switchgears. Furthermore, an improved method is proposed by adding the paralleled pure resistance, impedance or another LMCL element to protect the setup from the fault energy concentration in the setup. The problem of a slower arc voltage increasing rate can be solved by adding a paralleled impedance with suitable parameters. Finally, the current limiting properties based on the improved method were investigated and the alternating oscillating current was found between two paralleled LMCL elements owing to their deviation of arc ignition in reality. 展开更多
关键词 ARC liquid metal current limiter fluid pinch effect
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Evidence of vapor shielding effect on heat flux loaded on flowing liquid lithium limiter in EAST 被引量:1
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作者 Chenglong LI Guizhong ZUO +13 位作者 R MANIGI K TRITZ D ANDRUCZYK Bin ZHANG Ruirong LIANG D OLIVER Zhen SUN Wei XU Xiancai MENG Ming HUANG Zhongliang TANG Binfu GAO Ning YAN Jiansheng HU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期45-51,共7页
A lithium(Li)vapour layer was formed around a flowing liquid Li limiter to shield against the plasma incident power and reduce limiter heat flux in the EAST tokamak.The results revealed that after a plasma operation o... A lithium(Li)vapour layer was formed around a flowing liquid Li limiter to shield against the plasma incident power and reduce limiter heat flux in the EAST tokamak.The results revealed that after a plasma operation of a few seconds,the layer became clear,which indicated a strong Li emission with a decrease in the limiter surface temperature.This emission resulted in a dense vapour around the limiter,and Li ions moved along the magnetic fleld to form a green shielding layer on the limiter.The plasma heat flux loaded on the limiter,measured by the probe installed on the limiter,was approximately 52%lower than that detected by a fast-reciprocating probe at the same radial position without the limiter in EAST.Additionally,approximately 42%of the parallel heat flux was dissipated directly with the enhanced Li radiation in the discharge with the liquid metal infused trenches(LIMIT)limiter.This observation revealed that the Li vapour layer exhibited an excellent shielding effect to liquid Li on plasma heat flux,which is a possible beneflt of liquid-plasma-facing components in future fusion devices. 展开更多
关键词 liquid Li limiter Li vapor shielding heat flux EAST
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A novel fault current limiter topology design based on liquid metal current limiter 被引量:1
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作者 Jinjin LI Xiongying DUAN +4 位作者 Weiying XIE Zhihui HUANG Minfu LIAO Dequan WANG Xiaotao HAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第8期113-123,共11页
The liquid metal current limiter(LMCL)is regarded as a viable solution for reducing the fault current in a power grid.But demonstrating the liquid metal arc plasma self-pinching process of the resistive wall,and reduc... The liquid metal current limiter(LMCL)is regarded as a viable solution for reducing the fault current in a power grid.But demonstrating the liquid metal arc plasma self-pinching process of the resistive wall,and reducing the erosion of the LMCL are challenging,not only theoretically,but also practically.In this work,a novel LMCL is designed with a resistive wall that can be connected to the current-limiting circuit inside the cavity.Specifically,a novel fault current limiter(FCL)topology is put forward where the novel LMCL is combined with a fast switch and current-limiting reactor.Further,the liquid metal self-pinch effect is modeled mathematically in three dimensions,and the gas-liquid two-phase dynamic diagrams under different short-circuit currents are obtained by simulation.The simulation results indicate that with the increase of current,the time for the liquid metal-free surface to begin depressing is reduced,and the position of the depression also changes.Different kinds of bubbles formed by the depressions gradually extend,squeeze,and break.With the increase of current,the liquid metal takes less time to break,but breaks still occur at the edge of the channel,forming arc plasma.Finally,relevant experiments are conducted for the novel FCL topology.The arcing process and current transfer process are analyzed in particular.Comparisons of the peak arc voltage,arcing time,current limiting efficiency,and electrode erosion are presented.The results demonstrate that the arc voltage of the novel FCL topology is reduced by more than 4.5times and the arcing time is reduced by more than 12%.The erosions of the liquid metal and electrodes are reduced.Moreover,the current limiting efficiency of the novel FCL topology is improved by 1%–5%.This work lays a foundation for the topology and optimal design of the LMCL. 展开更多
关键词 liquid metal current limiter(LMCL) arc plasma fault current limiter(FCL)topology
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Study on the formation of arc plasma on the resistive wall liquid metal current limiter
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作者 李金金 段雄英 +4 位作者 黄智慧 谢为赢 廖敏夫 马畅 陶佳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期141-152,共12页
Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designe... Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designed to advance the starting current-limiting time.Experiments are performed to investigate the dynamic behaviors of liquid metal,and the influence of different currents on the liquid metal self-shrinkage effect is compared and analyzed.Furthermore,the liquid metal self-shrinkage effect is mathematically modeled,and the reason for the formation of arc plasma is obtained by simulation.The laws of arc plasma formation and the current transfer in the cavity are revealed,and the motion mechanisms are explained by physical principles.The simulations are in accordance with the test data.It is demonstrated that the sudden change of the current density at both ends of the wall causes the liquid metal to shrink and depress under the electromagnetic force,and the current starts to transfer from the liquid metal path to the wall resistance path.The RWLMCL can effectively advance the starting current-limiting time. 展开更多
关键词 resistive wall liquid metal current limiter(RWLMCL) liquid metal self-shrinkage effect arc plasma current transfer
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LOW MACH NUMBER LIMIT OF A COMPRESSIBLE NON-ISOTHERMAL NEMATIC LIQUID CRYSTALS MODEL 被引量:1
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作者 Jishan FAN Fucai LI 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期449-460,共12页
In this paper, we study the low Mach number limit of a compressible nonisothermal model for nematic liquid crystals in a bounded domain. We establish the uniform estimates with respect to the Mach number, and thus pro... In this paper, we study the low Mach number limit of a compressible nonisothermal model for nematic liquid crystals in a bounded domain. We establish the uniform estimates with respect to the Mach number, and thus prove the convergence to the solution of the incompressible model for nematic liquid crystals. 展开更多
关键词 COMPRESSIBLE NON-ISOTHERMAL liquid CRYSTALS BOUNDED domain low MACH number limit
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Optical Limiting and Stabilization Properties of a Liquid Dye on 1064 nm Nanosecond Laser Pulses
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作者 Liuheng Wang Rongzong Peng +1 位作者 Yuxia Zhao Feipeng Wu 《Optics and Photonics Journal》 2013年第2期34-37,共4页
A novel liquid dye 2-((2E,5E)-2,5-bis(4-(methyl(2,5, 8,11-tetraoxatridecan-13-yl)amino)benzylidene)cyclopentylidene) malononitrile (TO-BDCM) was synthesized by incorporating two oligo(ethenyl glycol) groups into the b... A novel liquid dye 2-((2E,5E)-2,5-bis(4-(methyl(2,5, 8,11-tetraoxatridecan-13-yl)amino)benzylidene)cyclopentylidene) malononitrile (TO-BDCM) was synthesized by incorporating two oligo(ethenyl glycol) groups into the backbone of a prototype malononitrile derivative (BDCM) for the purpose of increasing its solubility in organic solvents. The nonlinear absorption properties of this liquid dye on 1064 nm ns pulsed laser were investigated in DMF with remarkably high concentration up to ~1M, showing a superior large nonlinear absorption coefficient of 55.6 cm3/GW2. Fairly good optical limiting and stabilization effects were achieved. Meanwhile, the liquid dye exhibited equivalent stability under laser irradiation compared to its prototype dye BDCM. 展开更多
关键词 liquid DYE MULTIPHOTON Absorption OPTICAL limitING OPTICAL STABILIZATION
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高速公路高液限土路基填料改良方案试验研究
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作者 王立祥 《价值工程》 2026年第2期4-6,共3页
本文针对国道G360公路沿线高液限土,开展系统的物理性质研究。为使路基指标满足验收弯沉要求,采用325普通硅酸盐水泥对高液限土进行改良,通过对比试验检测改良前后土样的各项物理化学性质。结合理论分析与施工现场试验数据,明确了水泥... 本文针对国道G360公路沿线高液限土,开展系统的物理性质研究。为使路基指标满足验收弯沉要求,采用325普通硅酸盐水泥对高液限土进行改良,通过对比试验检测改良前后土样的各项物理化学性质。结合理论分析与施工现场试验数据,明确了水泥掺杂比例与土样物理性质的关联规律,得出最优现场施工方法,并对施工现场应用中的关键施工工艺及控制措施进行了深入研究与分析。研究确定,本段公路施工中上路床采用5%普通硅酸盐水泥改良、下路床采用4%普通硅酸盐水泥改良、路堤采用3%普通硅酸盐水泥改良。该研究结果可为G360公路高液限土改良施工提供直接参考,同时也能为同类公路路堤施工中高液限土改良问题提供借鉴。 展开更多
关键词 高液限土 弯沉 物理性质 改良
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改良高液限粘土的水泥/硅微粉材料比值优化及性能测试
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作者 高林 吴龙生 《粘接》 2026年第2期397-400,共4页
为改善软土地质中高液限粘土的性能,试验选用取样深度为1.5 m的高液限粘土,通过添加不同配比的硅酸盐水泥与硅微粉,同时进行一系列性能测试,得到了水泥硅微粉改良高液限粘土的最佳配比,并搭建试验平台,对最佳改良配比所得的高液限粘土... 为改善软土地质中高液限粘土的性能,试验选用取样深度为1.5 m的高液限粘土,通过添加不同配比的硅酸盐水泥与硅微粉,同时进行一系列性能测试,得到了水泥硅微粉改良高液限粘土的最佳配比,并搭建试验平台,对最佳改良配比所得的高液限粘土进行边坡稳定性测试。结果表明,采用水泥与硅微粉对高液限粘土进行改良;水泥硅微粉的添加可以降低高液限粘土的含水率和干密度;养护时间越长,土样的抗压强度也越好,硅微粉∶水泥以3∶7的配比所制备的3%-SP/P·Ι/高液限粘土复合土样的力学性能最好,可以用作道路工程加固;在上述最佳配比方案下,加固角度45、加固厚度1.0 m时边坡的安全系数最好,在实际应用中,结合现场实际和应用成本,可以选择更为合适的加固方案。 展开更多
关键词 软土地质 高液限粘土 硅酸盐水泥 硅微粉 边坡安全系数
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Computational fluid dynamic simulations on liquid film behaviors at flooding in an inclined pipe
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作者 陈建业 唐媛 +3 位作者 张伟 王宇辰 邱利民 张小斌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第9期1460-1468,共9页
The complex liquid film behaviors at flooding in an inclined pipe were investigated with computational fluid dynamic(CFD) approaches. The liquid film behaviors included the dynamic wave characteristics before flooding... The complex liquid film behaviors at flooding in an inclined pipe were investigated with computational fluid dynamic(CFD) approaches. The liquid film behaviors included the dynamic wave characteristics before flooding and the transition of flow pattern when flooding happened. The influences of the surface tension and liquid viscosity were specially analyzed. Comparisons of the calculated velocity at the onset of flooding with the available experimental results showed a good agreement. The calculations verify that the fluctuation frequency and the liquid film thickness are almost unaffected by the superficial gas velocity until the flooding is triggered due to the Kelvin–Helmholtz instability. When flooding triggered at the superficial liquid velocity larger than0.15 m·s-1, the interfacial wave developed to slug flow, while it developed to entrainment flow when it was smaller than 0.08 m·s-1. The interfacial waves were more easily torn into tiny droplets with smaller surface tension, eventually evolving into the mist flow. When the liquid viscosity increases, the liquid film has a thicker holdup with more intensive fluctuations, and more likely developed to the slug flow. 展开更多
关键词 Two phase flow Flooding Countercurrent flow limitation Computational fluid dynamic liquid film Inclined pipe
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干旱气候下高液限黏土质堤防裂隙演变分析 被引量:1
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作者 程诚 张春林 刘金杰 《江淮水利科技》 2025年第1期31-35,共5页
随着全球气候变化加剧,出现极端干旱气候的频率逐渐增加,干旱气候会使高液限黏土质堤防失水收缩产生裂缝。通过室内相似试验、数字图像处理技术以及数值模拟,研究了淮北大堤高液限黏土质堤防的裂隙发育规律。研究结果表明:数字图像处理... 随着全球气候变化加剧,出现极端干旱气候的频率逐渐增加,干旱气候会使高液限黏土质堤防失水收缩产生裂缝。通过室内相似试验、数字图像处理技术以及数值模拟,研究了淮北大堤高液限黏土质堤防的裂隙发育规律。研究结果表明:数字图像处理技术可以高效、准确地识别试样表面的裂隙,有助于分析裂隙发育的趋势;在干燥过程中,堤顶部位裂隙度发育过程分为缓慢发育、快速发育和稳定发育三个阶段;不均匀的光照会加剧堤顶部位的裂隙发育。 展开更多
关键词 高液限黏土 堤防 干缩裂隙 裂隙度 演变分析
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土中吸附水研究综述及其在路基工程中的应用展望
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作者 张锐 李露 +2 位作者 胡绍杰 苟凌云 张超 《中国公路学报》 北大核心 2025年第11期283-307,共25页
土中孔隙水一直是土力学研究中的热点及难点问题,其物理特性是高液限土、软土等特殊土力学规律研究中的共性关键科学问题。土中孔隙水依赋存状态可分为自由水和吸附水,其中吸附水具有高密度、强结构性等独特物理性质,表现出与自由水截... 土中孔隙水一直是土力学研究中的热点及难点问题,其物理特性是高液限土、软土等特殊土力学规律研究中的共性关键科学问题。土中孔隙水依赋存状态可分为自由水和吸附水,其中吸附水具有高密度、强结构性等独特物理性质,表现出与自由水截然不同的流动和相变行为。目前,吸附水物理性质对土体渗透、强度及变形特性的影响规律尚不明确,且实际工程对吸附水关注较少,未能充分利用其物理特性优化工程实践。重点综述了土中吸附水及其对土体特性影响规律的最新研究进展,介绍了微观、细观和宏观等多个尺度的理论和试验研究成果:系统归纳了吸附水的形成机制,分析了吸附水与毛细水的物理性质及差异,阐明了吸附水对土体水力和力学特性的影响规律;分析了吸附水对土体渗透特性影响的试验研究现状,并介绍了考虑吸附作用的渗透系数模型最新进展;归纳了吸附水对土体强度演化规律影响的试验研究现状,介绍了考虑吸附水影响的强度理论模型最新进展;总结了吸附水对土体压缩变形、蠕变变形及路基土回弹特性影响的研究进展,重点分析了吸附水在高液限土和软土蠕变特性中的作用;分析了吸附水特性在高液限土路堤和软土地基工程中的潜在应用前景,并展望了未来研究的重点和方向,为后续研究提供参考。 展开更多
关键词 路基工程 吸附水 综述 高液限土 软土 力学特性 微观机制
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赤泥复合固化剂固化粉土路用性能及其机理 被引量:2
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作者 吴伟军 张鲲鹏 +2 位作者 张宁 丁北斗 王佳辉 《建筑材料学报》 北大核心 2025年第3期227-235,共9页
利用工业废弃物赤泥、电石渣和脱硫石膏组成的赤泥复合固化剂对低液限粉土进行固化,探究了固化粉土的力学性能(无侧限抗压强度和劈裂强度)和耐久性(水稳定性和干湿循环),并采用扫描电镜(SEM)和X射线衍射仪(XRD)分析赤泥复合固化剂的固... 利用工业废弃物赤泥、电石渣和脱硫石膏组成的赤泥复合固化剂对低液限粉土进行固化,探究了固化粉土的力学性能(无侧限抗压强度和劈裂强度)和耐久性(水稳定性和干湿循环),并采用扫描电镜(SEM)和X射线衍射仪(XRD)分析赤泥复合固化剂的固化机理.结果表明:固化粉土的无侧限抗压强度和劈裂强度随着赤泥复合固化剂掺量的增加和养护龄期的延长而提高;当赤泥复合固化剂掺量由8%增至24%且养护龄期由7 d延至28 d时,固化粉土的水稳系数由69.5%提高到82.4%;干湿循环12次后,固化粉土的强度损失率为35.14%.赤泥复合固化剂掺入粉土中发生水化反应,生成具有胶凝作用的水化硅酸钙(C-S-H)和水化铝酸钙(C-A-H)凝胶,同时C-A-H与CaSO_(4)生成钙矾石(AFt)晶体;C-S-H和C-A-H包裹并填充着土颗粒,AFt晶体穿插在土颗粒间,使其成为一个整体,有效提高了固化粉土的路用性能. 展开更多
关键词 赤泥 低液限粉土 路用性能 固化机理
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原料土液限对自密实固化土工程性质的影响 被引量:2
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作者 徐婕 梁剑辉 +2 位作者 齐乐 龚英 高玉峰 《硅酸盐通报》 北大核心 2025年第1期360-367,共8页
自密实固化土凭借就地取土、协同处置建筑垃圾、自流平、易泵送的优点在多种回填工程中得到了广泛应用。本文通过流动度试验、泌水率试验、湿密度试验、干缩试验和无侧限抗压强度试验,探究了原料土液限对自密实固化土性质的影响,并借助... 自密实固化土凭借就地取土、协同处置建筑垃圾、自流平、易泵送的优点在多种回填工程中得到了广泛应用。本文通过流动度试验、泌水率试验、湿密度试验、干缩试验和无侧限抗压强度试验,探究了原料土液限对自密实固化土性质的影响,并借助自由水分离试验探讨了自由水含量对强度特征的作用机理。结果表明:在相同水泥掺量和掺水率条件下,以高液限黏土为原料土制成的自密实固化土新拌浆体流动度较低,固化后无侧限抗压强度较高;随着掺水率的增加,新拌浆体的流动度增长幅度基本保持不变,固化后的无侧限抗压强度降低幅度开始减少;任意龄期条件下,以高液限黏土为原料土制成的自密实固化土中自由水含量均较低。在7 d养护龄期时,以高液限黏土为原料土制成的自密实固化土中自由水含量仅为2.2%,而低液限黏土自密实固化土试样的自由水含量为11.7%。该研究成果揭示了不同原料土液限对自密实固化土中自由水含量的影响机制,可为工程实践中原料土的选择及其配比设计提供指导。 展开更多
关键词 自密实固化土 液限 自由水 流动度 无侧限抗压强度
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脲酶诱导碳酸钙加固库区岸坡低液限黏土试验研究 被引量:1
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作者 于凡 赵卫全 +2 位作者 安裕民 耿会岭 赵永刚 《中国水利水电科学研究院学报(中英文)》 北大核心 2025年第3期216-225,233,共11页
由于库区水位周期性涨落,岸坡土体经常受到水的浸泡、冲刷和侵蚀,严重影响库区岸坡的稳定性。脲酶诱导碳酸钙沉淀(EICP)可以改善土体的物理力学性质。为探究EICP技术在库区岸坡加固方面的应用,以亳州调蓄水库岸坡低液限黏土为研究对象,... 由于库区水位周期性涨落,岸坡土体经常受到水的浸泡、冲刷和侵蚀,严重影响库区岸坡的稳定性。脲酶诱导碳酸钙沉淀(EICP)可以改善土体的物理力学性质。为探究EICP技术在库区岸坡加固方面的应用,以亳州调蓄水库岸坡低液限黏土为研究对象,开展胶结液浓度配比、无侧限抗压强度及直剪试验,得出了考虑“钙源沉淀系数γ”“尿素水解系数β”及碳酸钙沉淀的胶结液浓度优化配比,探究了EICP加固低液限黏土的单轴抗压特性和破坏模式以及抗剪力学特性。结果表明,脲酶浓度为100 g L时,同一胶结液浓度配比下,氯化钙浓度阈值为1.5 mol L,高于该浓度阈值时,对脲酶催化反应速率影响较大,碳酸钙沉淀量增速减缓。胶结液浓度配比为1∶1,氯化钙浓度为1.5 mol L时,氯化钙和尿素利用效率均较高,且碳酸钙沉淀量较多,“钙源沉淀系数γ”“尿素水解系数β”均为1.64。EICP能够改善低液限黏土的力学特性,相较于素土,EICP加固后无侧限抗压强度提升1.9倍,其破坏模式为剪切破坏。EICP加固后黏聚力、内摩擦角分别增长约51.61%、4.67%。研究结果可为库区生态岸坡的建设提供参考。 展开更多
关键词 脲酶诱导碳酸钙 库区岸坡 低液限黏土 胶结液浓度配比 力学特性 钙源沉淀系数 尿素水解系数
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内陆盐渍土地区路基阻盐隔断层设置模拟试验
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作者 裘友强 张留俊 +2 位作者 刘洋 邵磊 刘军勇 《应用基础与工程科学学报》 北大核心 2025年第2期599-609,共11页
为了防止盐分随毛细水向上迁移造成路基次生盐渍化,针对内陆盐渍土地区广泛分布的低液限黏土和砾类土2种路基填料,通过自行设计的室内路基水盐迁移模拟试验装置,对比分析不同设置部位的隔断层对毛细水和盐分的阻断作用,揭示毛细水与盐... 为了防止盐分随毛细水向上迁移造成路基次生盐渍化,针对内陆盐渍土地区广泛分布的低液限黏土和砾类土2种路基填料,通过自行设计的室内路基水盐迁移模拟试验装置,对比分析不同设置部位的隔断层对毛细水和盐分的阻断作用,揭示毛细水与盐分迁移的时间效应.研究结果表明:在地下水充足供给的内陆盐渍土地区,无论是采用低液限黏土还是级配良好砾作为路基填料,若隔断层设置于路床下部,毛细水均可通过路基上升至隔断层内10~15cm处稳定,且含盐量增加较小,砾石隔断层能有效阻止毛细水的上升,避免路基的次生盐渍化,可满足低路基修筑的隔断要求;对比设置于路基底部和路床下部的2种隔断层工况,前者毛细水在隔断层内的上升高度为15~20cm,后者毛细水在隔断层内的上升高度为10~15cm,这说明隔断层设置于路床下部对于其上路床和路面结构更为安全;由于设置于路基底部的隔断层易受地表径流或降雨积水的浸泡影响,该隔断层应设置于历史最高洪水位之上,且安全高度不宜小于50cm;相较于砾类土路基,毛细水在黏土路基内部迁移高度更大,且迁移稳定所需时间更长. 展开更多
关键词 内陆盐渍土地区 路基工程 隔断层 模拟试验 水盐迁移 阻盐效果 低液限黏土 砾类土
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基于孔压静力触探预测软弱土压缩指数研究 被引量:1
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作者 陈凯 林军 +1 位作者 闫超 魏明俐 《土工基础》 2025年第4期653-657,共5页
土的压缩指数C_(c)评估对土体的沉降有着重要意义,会对基础的大小和尺寸设计产生影响。分析了孔隙比e、含水率w_(n)、液限w_(L)三个土的物理参数和C_(c)之间的相关性并提出了经验公式,结果表明,孔隙比e、含水率w_(n)、液限w_(L)和C_(c)... 土的压缩指数C_(c)评估对土体的沉降有着重要意义,会对基础的大小和尺寸设计产生影响。分析了孔隙比e、含水率w_(n)、液限w_(L)三个土的物理参数和C_(c)之间的相关性并提出了经验公式,结果表明,孔隙比e、含水率w_(n)、液限w_(L)和C_(c)间具有良好的相关性,决定系数分别为0.837 5、0.823 3、0.691。同时,重点关注孔压静力触探(CPTU)现场原位测试技术,根据获取的南京市某经济住房项目的CPTU试验数据,结合土工实验数据,对土的压缩指数Cc进行了分析,评估了静力触探预测Cc的准确度。结果表明,锥尖阻力q_(c)可以有效预测C_(c),不同土层的压缩因α_(m)取值不同(黏土>粉质黏土>砂土),当压缩因子α_(m)确定时,通过预测公式可准确获得各土层的C_(c)参数,对各土层压缩性进行评估。 展开更多
关键词 孔压静力触探 压缩指数 孔隙比 含水率 液限
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