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| 1 | Dynamic behavior of new cutting subgrade structure of expensive soil under train loads coupling with service environment显示文摘Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. Aimed at a high-speed railway engineering practice in the newly built Yun-Gui high-speed railway expansive soil section in China, indoor vibration test on a full-scaled new cutting subgrade model is carried out. Based on the established track-subgrade-foundation of expansive soil system dynamic model test platform, dynamic behavior of new cutting subgrade structure under train loads coupling with extreme service environment(dry, raining, and groundwater level rising) is analyzed comparatively. The results show that the subgrade dynamic response is significantly influenced by service conditions and the dynamic response of subgrade gradually becomes stable with the increasing vibration times under various service environment conditions. The vertical dynamic soil stress is related with the depth in an approximate exponential function, and the curves of vertical dynamic soil stress present a 'Z' shape distribution along transverse distance. The peak value of dynamic soil stress appears below the rail, and it increases more obviously near the roadbed surface. However, the peak value of dynamic soil stress is little affected outside 5.0 m of center line. The vibration velocity and acceleration are in a quadratic curve with an increase in depth, and the raining and groundwater level rising increase both the vibration velocity and the acceleration. The vertical deformations at different depths are differently affected by service environment in roadbed. The deformation of roadbed increases sharply when the water gets in the foundation of expansive soil, and more than 60% of the total deformation of roadbed occurs in expansive soil foundation. The laid waterproofing and drainage structure layer, which weakens the dynamic stress and improves the track regularity, presents a positive effect on the control deformation of roadbed surface. An improved empirical formula is then proposed to predict the dynamic stress of ballasted tracks subgrade of expansive soil. | 邱明明 杨果林 申权 杨啸 王刚 林宇亮 | 2017 | Journal of Central South University2017，24，4： | 13 |
| 2 | Emerging trends in expansive soil stabilisation: A review显示文摘Expansive soils are problematic due to the performances of their clay mineral constituent, which makes them exhibit the shrink-swell characteristics. The shrink-swell behaviours make expansive soils inappropriate for direct engineering application in their natural form. In an attempt to make them more feasible for construction purposes, numerous materials and techniques have been used to stabilise the soil. In this study, the additives and techniques applied for stabilising expansive soils will be focused on,with respect to their efficiency in improving the engineering properties of the soils. Then we discussed the microstructural interaction, chemical process, economic implication, nanotechnology application, as well as waste reuse and sustainability. Some issues regarding the effective application of the emerging trends in expansive soil stabilisation were presented with three categories, namely geoenvironmental,standardisation and optimisation issues. Techniques like predictive modelling and exploring methods such as reliability-based design optimisation, response surface methodology, dimensional analysis, and artificial intelligence technology were also proposed in order to ensure that expansive soil stabilisation is efficient. | Chijioke Christopher Ikeagwuani Donald Chimobi Nwonu | 2019 | Journal of Rock Mechanics and Geotechnical Engineering2019，11，2： | 13 |
| 3 | 侧限条件下膨胀土膨胀试验研究显示文摘选取某工程段膨胀土做室内无荷膨胀率试验,研究了在侧限条件下膨胀土的膨胀时程特征,分析了无荷膨胀率与压实度、初始含水率之间的关系。结果表明:膨胀土的膨胀变形可分为急剧膨胀、膨胀衰减、膨胀稳定三个阶段;初始含水率相同时,压实度越小的土样在起始膨胀阶段的膨胀速率越大,最终膨胀量越小;压实度相同时,初始含水率越小的土样在膨胀变形的前两个阶段膨胀速率越大,最终膨胀量也越大;无荷膨胀率与压实度线性正相关,与初始含水率线性负相关。初始含水率对无荷膨胀率的影响大于压实度。并基于试验结果建立了反映初始含水率、压实度影响的无荷膨胀率方程,与实测结果对比表明,方程合理、有效。 | 姚华彦 吴云刚 黄斌 | 2010 | 水电能源科学2010，28，7： | 12 |
| 4 | 膨胀土(岩)渠坡自动化综合监测系统研究显示文摘膨胀土(岩)是一种多裂隙性、胀缩性地质体,其黏土矿物具有强亲水性,土体胀缩作用对渠道工程具有严重破坏性。因此,在对膨胀土渠坡监测过程中,除传统的渠坡变形等监测项目外,土壤含水量、吸力等是一个新的重要监测量,此外,膨胀土(岩)受含水量变化产生的反复胀缩变形以及开挖和降雨等因素引起的变形规律的研究,都是传统监测方法和手段无法完成的任务。研究提出了一种基于传感器、互联网、土木工程和计算机等技术的渠坡位移、水位、水分、水势、土温、气温、降雨量以及坡面梁结构钢筋计等多传感器的自动化综合监测系统。实现对膨胀土(岩)渠坡(或边坡)进行实时在线自动化监测、无线数传、数据的电脑和手机客户端管理与浏览以及预警等功能,为研究膨胀土(岩)渠坡变形破坏机理及处理设计有效性评价提供了基础资料和依据。 | 刘祖强 吕笑 龚文慈 张占彪 熊颢 | 2014 | 人民长江2014，45，7： | 8 |
| 5 | Anisotropic singular integrals in product spaces显示文摘In this paper, the authors introduce a class of product anisotropic singular integral operators, whose kernels are adapted to the action of a pair A := (A1, A2) of expansive dilations on R n and R m , respectively. This class is a generalization of product singular integrals with convolution kernels introduced in the isotropic setting by Fefferman and Stein. The authors establish the boundedness of these operators in weighted Lebesgue and Hardy spaces with weights in product A∞ Muckenhoupt weights on R n × R m . These results are new even in the unweighted setting for product anisotropic Hardy spaces. | BOWNIK Marcin | 2010 | Science China Mathematics2010，53，12： | 7 |
| 6 | Expansive arterial remodeling of carotid arteries in symptomatic ischemic patients显示文摘Purpose: The present study aimed to assess the associations of expansive remodeling of carotid arteries with ischemic symptoms and the degree of stenosis. Materials and Methods: A total of 41 symptomatic patients with vulnerable plaques and 25 asymptomatic individuals with stable plaques were included. All patients underwent 3.0T high-resolution MRI of the carotid artery(CA) for measuring the expansive remodeling(ER) ratio and assessing plaque stability. The ER ratio was calculated by dividing the maximum distance between the lumen and the outer border of the plaque in the internal CA by the lumen diameter within 1 centimeter of the plaque at the distal ipsilateral internal CA. ER ratios were compared between the symptomatic and asymptomatic groups. The 41 symptomatic patients were further divided into 4 groups according to stenosis rate(CA stenosis <50%, 50%–74%, 75–89%, and > 90%), and the correlation between the ER ratio and the rate of stenosis was evaluated. Results: There was a significant difference in ER ratio between the symptomatic and asymptomatic groups(p<0.001). When symptomatic patients were divided into 4 subgroups based on degree of stenosis, ER ratios among groups showed statistically significant differences(p=0.014). Conclusion: There were significant associations of the ER ratio with ischemic symptoms. Furthermore, the ER ratio in symptomatic patients continued to increase with stenosis severity. These findings suggested that the ER ratio might be a practical marker of plaque vulnerability in the CA and further prospective studies for asymptomatic patients are warranted. | Zheyi Chen Mei Li Minghua Li Yuwu Zhao Yueqi Zhu | 2018 | Journal of Interventional Medicine2018，1，2： | 5 |
| 7 | Continuous maps with the whole space being a scrambled set显示文摘1 A problem or scrambled setCHAOTIC behavior is a manifestation of complexity of nonlinear dynamical systems. Since theobjects, methods, aims, or emphases of study are distinct, there are some variant definitionsof chaos given by different authors, or given by the same author in his different works. Thefollowing definition mainly stems from Li and Yorke. | MAI JiehuaInstitute of Mathematics, Shantou University, Shantou 515063, China | 1997 | Chinese Science Bulletin1997，42，19： | 5 |
| 8 | Sugarcane press mud modification of expansive soil stabilized at optimum lime content:Strength,mineralogy and microstructural investigation显示文摘This study attempted to investigate the potential of sugarcane press mud(PM) as a secondary additive in conjunction with lime for the stabilization of an expansive soil.The physico-mechanical properties of an expansive soil,such as plasticity,shrink-swell behavior,unconfined compressive strength(UCS),mineralogical and microstructural characteristics were investigated.The expansive soil was stabilized at its optimum lime content(7%) for producing maximum strength,and was modified with four different quantities of PM in small dosages(0.25%-2%).Cylindrical soil samples,38 mm in diameter and 76 mm in height,were cast and cured for varying periods to evaluate the strength of the amended soil.The spent samples after strength tests were further used for determination of other properties.The test results revealed that PM modification led to a substantial improvement in 7-d strength and noticeable increase in 28-d strength of the lime-stabilized soil(LSS).The addition of PM does not cause any detrimental changes to the shrink-swell properties as well as plasticity nature of the stabilized soil,despite being a material of organic origin.Mineralogical investigation revealed that the formation of calcium silicate hydrate(CSH) minerals,similar to that of pure lime stabilization with only the type of mineral varying due to the modification of PM addition,does not significantly alter the microstructure of the LSS except for superficial changes being noticed. | Jijo James | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，2： | 5 |
| 9 | Review of methods for predicting in situ volume change movementof expansive soil over time显示文摘The soil movement information over time is required for the design of foundations placed in expansive soils. This information is also helpful for the assessment of pre-wetting and controlled wetting mitigation alternatives for expansive soils. Several researchers during the past fifteen years have proposed different methods for the prediction of the soil movements over time. The available methods can be categorized into(i) consolidation theory-based methods,(ii) water content-based methods, and(iii) suction-based methods. In this paper, a state-of-the-art of the prediction methods is succinctly summarized. The methods are critically reviewed in terms of their predictive capacity along with their strengths and limitations. The review highlights the need for prediction methods that are conceptually simple yet efficient for use in conventional engineering practice for different types of expansive soils. | Hana H. Adem Sai K. Vanapalli | 2015 | 岩石力学与工程学报2015，34，1： | 3 |
| 10 | Cracking in an expansive soil under freeze–thaw cycles显示文摘Expansive soils located in cold regions can easily endure the action of frost heaving and cyclic freezing–thawing. Cracking can also occur in expansive clayey soils under freeze–thaw cycles, of which little attention has been paid on this issue.In this study, laboratory experiment and cracking analysis were performed on an expansive soil. Crack patterns were quantitatively analyzed using the fractal concept. The relationships among crack pattern, water loss, number of freeze–thaw cycles, and fractal dimension were discussed. It was found that crack patterns on the surface exhibit a hierarchical network structure that is fractal at a statistical level. Cracks induced by freeze–thaw cycles are shorter, more irregularly oriented,and slowly evolves from an irregularly rectilinear pattern towards a polygonal or quasi–hexagonal one; water loss, closely related to specimen thickness, plays a significant role in the process of soil cracking; crack development under freeze-thaw cycles are not only attributed to capillary effect, but also to expansion and absorption effects. | Yang Lu SiHong Liu | 2017 | Research in Cold and Arid Regions2017，9，4： | 2 |
| 11 | THE BOUNDEDNESS FOR COMMUTATORS OF ANISOTROPIC CALDERóN-ZYGMUND OPERATORS显示文摘Let T be an anisotropic Calderón-Zygmund operator andφ:R^n×[0,∞)→[0,∞)be an anisotropic Musielak-Orlicz function withφ(x,·)being an Orlicz function andφ(·,t)being a Muckenhoupt A∞(A)weight.In this paper,our goal is to study two boundedness theorems for commutators of anisotropic Calderon-Zygmund operators.Precisely,when b∈BMOw(R^n,A)(a proper subspace of anisotropic bounded mean oscillation space BMO(R^n,A)),the commutator[b,T]is bounded from anisotropic weighted Hardy space H^1ω(R^n,A)to weighted Lebesgue space L^1ω(R^n)and when b∈BMO(R^n)(bounded mean oscillation space),the commutator[b,T]is bounded on Musielak-Orlicz space L^φ(R^n),which are extensions of the isotropic setting. | 李金霞 李宝德 何建勋 | 2020 | Acta Mathematica Scientia2020，40，1： | 1 |
| 12 | Theory and practice concerning classification for expansive soils using standard moisture absorption water content显示文摘A series of tests on physical, mechanical and chemical properties of expansive soils have shown that the standard moisture absorption water content (SMA) of expansive soils has a good linear relationship with montmorillonite content, cation exchange capacity, specific surface, and it also presents a linear relationship tendency to plastic index and free swell ratio. All this indicates that the above SMA is of clear significance in physics. The plastic index can better reflect the interaction extent between composition and dispersing character of grains, cation and clay minerals. Consequently, SMA can reflect the basic essential properties of expansive soils. On the basis of the classification results that have been published in literature and in consideration of the succession to the classification results for the free swell ratio, this paper puts forward three indexes, i.e. the SMA, plastic index and free swell ratio to classify expansive soils. The tests proposed for the classification indexes are easy to operate, simple in testing device and last a short time. Compared with the latest issued “Classification Standard Code for Rocks and Soils of Railway Projects” (TB10077-2001), the method proposed in this paper is more convenient and reasonable, and can be popularized, when environment conditions ripen, for the application in field of exploration and design of highway in the areas surrounded by expansive soils. | YAO Hailin1, CHENG Ping2, YANG Yang1 & WU Wanping2 1. Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China 2. China Communications Second Highway Survey Design and Research Institute, Wuhan 430052, China | 2005 | Science China(Technological Sciences)2005，48，1： | 1 |
| 13 | Properties of Ettringite Type Expansive Agent显示文摘By employing different forms and amounts of materials , many kinds of ettringite type expansive agents had been prepared. The relationship between the compositions and properties of expansive agents was analyzed . The design methods of expansive agent have been put forward according to the property requirement of expansive concrete. | 李悦 | 2001 | Journal of Wuhan University of Technology(Materials Science)2001，16，4： | 1 |
| 14 | Swelling characteristics of andesite foundation induced by water immersion and their influence on ballastless track subgrade显示文摘To study the mechanical and deformation characteristics of ballastless track subgrade filled with micro-expansion fillers in a water-immersed environment, a physical model of ballastless track subgrade was constructed on a 1:2 scale with expansive andesite fillers. A water immersion test was carried out to model the soaking of the expansive soil foundation caused by rising groundwater. The swelling behaviors of the foundation and their influences upon the mechanics and deformations of the subgrade were analyzed. The lateral swelling pressure of the foundation and the heave of the subgrade obviously increased due to the water immersion, and the values were closely related to the overlying load and lateral restraint. The heave deformation of the double-line ballastless track subgrade showed significant nonuniformity along the lateral direction, causing the track slab to incline with a maximum inclination angle of 1.55×10^-3 deg. The heave of the foundation caused a heave in subgrade, but this transferred heave was significantly attenuated. The attenuation rate of the heave at the midline of the track slab was up to 13.38%. The attenuation characteristic can be fully utilized for the anti-heave deformation measures of railway subgrade in expansive soil areas. | DUAN Jun-yi YANG Guo-lin HU Min LEI Xiao-qin LIN Yu-liang | 2020 | Journal of Mountain Science2020，17，4： | 1 |
| 15 | 论邓小平的青年人才思想显示文摘论邓小平的青年人才思想王莉萍建设有中国特色的社会主义理论是一个科学的体系,其中,邓小平同志的青年人才思想占有突出的地位并成为这个体系中的重要组成部分。邓小平同志应用马克思列宁主义毛泽东思想的人才理论,结合新时期建设有中国特色社会主义事业的伟大实践,创... | 王莉萍 | 1995 | 内蒙古社会科学1995，16，4： | 0 |
| 16 | Assessment of Ornamental Stone Waste as Expansive Soil Stabilizer显示文摘This work aims to assessment of the calcitic ornamental stone waste for the stabilization of expansive soil. Calcitic rock-derived waste together with different expansive soils from Egypt were characterized and processed for stabilizer optimization. The mineral, chemical and engineering characteristics of the waste and the soil samples were examined using XRD, DTA, TGA, SEM, XRF as well as geotechnical characteristics such as liquid, plastic and shrinkage limits, plasticity index, free swelling, and uni-axial compressive strength, respectively. The calcitic waste has been calcined in an electrical muffle furnace at 1000℃ for 1 hour. The samples were treated by 0–8% waste post calcination for soaking time1– 4 weeks. | Abdel Monem M Soltan.Waleed A.Ogila | 2013 | 矿物学报2013，33，S1： | 0 |
| 17 | NUMERICAL METHOD AND RANDOM ANALYSIS OF CEMENT CONCRETE EXPANSION显示文摘The numerical method and random analysis of cement concrete expansion are given.A mathematical procedure is presented which includes the nonlinear charac teristics of the concrete.An expression is presented to predict the linear restrained expansion of expansive concrete bar restrained by a steel rod.The results indicate a rapid change in strains and stresses within initial days, after which the change gradually decreases.A reliable and accurate method of predicting the behavior of the concrete bulkheads in drifts is presented here.Extensive sensitivity and parametric studies have been performed. The random density distributions of expansive concrete are given based on the restricted or unrestricted condition. These studies show that the bulkhead stress fields are largely influenced by the early modulus of the concrete and the randomness of the ultimate unrestrained expansion of the concrete. | 管昌生 | 2000 | Journal of Wuhan University of Technology(Materials Science)2000，15，1： | 0 |
| 18 | 正确的人才培养战略是民族高等院校在新形势下获得发展的根本保证显示文摘正确的人才培养战略是民族高等院校在新形势下获得发展的根本保证呼格吉勒图(一)树立人才竞争观念,确立人才培养战略。随着现代社会方方面面的高速发展,随着我国社会主义市场经济体制的建立和完善,对外开放的不断扩大,以及国际间交流的不断加强,整个社会对高等院校... | 呼格吉勒图 | 1995 | 前沿1995，，10： | 0 |
| 19 | Behaviors of recycled aggregate concrete-filled steel tubular columns under eccentric loadings显示文摘The paper investigates the behaviors of recycled aggregate concrete-filled steel tubular(RACFST)columns under eccentric loadings with the incorporation of expansive agents.A total of 16 RACFST columns were tested in this study.The main parameters varied in this study are recycled coarse aggregate replacement percentages(0%,30%,50%,70%,and 100%),expansive agent dosages(0%,8%,and 15%)and an eccentric distance of compressive load from the center of the column(0 and 40 mm).Experimental results showed that the ultimate stresses of RACFST columns decreased with increasing recycled coarse aggregate replacement percentages but appropriate expansive agent dosages can reduce the decrement;the incorporation of expansive agent decreased the ultimate stresses of RACFST columns but an appropriate dosage can increase the deformation ability.The recycled coarse aggregate replacement percentages have limited influence on the ultimate stresses of the RACFST columns and has more effect than that of the normal aggregate concretesteel tubular columns. | Vivian W.Y.TAM Jianzhuang XIAO Sheng LIU Zixuan CHEN | 2019 | Frontiers of Structural and Civil Engineering2019，13，3： | 0 |
| 20 | 人才市场建设与人事制度改革显示文摘人才市场建设与人事制度改革张书琛党的十四大确立了建立社会主义市场经济体制的目标,人才市场也随之蓬勃发展起来。人才市场是计划体制向市场经济转轨的必然。目前,各级地方人事部门办的人才交流中心仍在全国的人才市场中居于主导地位;同时,各类性质的人才交流机构也... | 张书琛 | 1995 | 前沿1995，，6： | 0 |
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