Intact soft clay’s critical response to dynamic stress paths on different combinations of principal stress orientation

Comprehensive tests on Hangzhou intact soft clay were performed, which were used to obtain the soils’ critical response to undrained dynamic stress paths under different combinations of principal stress orientation. The different combinations included cyclic principal stress rotation (CPSR for short), cyclic shear with abrupt change of principal stress orientation (CAPSO for short) and cyclic shear with fixed principal stress orientation (CFPSO for short). On one side, under all these stress paths, samples have obvious strain inflection points and shear bands, and the excess pore water pressure is far from the level of initial effective confining pressure at failure. Stress paths of major principal stress orientation (α) alternating from negative and positive have quite different influence on soil’s properties with those in which α is kept negative or positive. On the other side, due to the soil’s strongly initial anisotropy, samples under double-amplitudes CPSR and CAPSO (or single-amplitude CPSR and CFPSO) have similar properties on dynamic shear strength and pore water pressure development tendency when α is kept within ±45°, while have quite different properties when α oversteps ±45°.     

解读连战先生的民族情

文章试图从两方面解读连战先生深厚的民族情.这种民族情一方面来源于他的家族,连战的先祖到台湾死也不臣服清,曾祖父至父亲三代以各种形式坚持抗日及父母对他言传身教;另一方面与他早年在祖国大陆的生活经历有关,从他对抗战和日本的态度及祖国大陆寻踪等方面体现出来.     

Evaluation of ultimate bearing capacity of Y-shaped vibro-pile

Based on Mindlin stress solution, a numerical computational method was proposed to calculate the stresses in the ground induced by side friction and the resistance of Y-shaped vibro-pile. The improved Terzaghi’s and ЪерезанцевВГ’s methods for ultimate bearing capacity evaluation were proposed by considering the stress strength induced by friction resistance at pile head level of Y-pile. A new method to calculate the ultimate bearing capacity of Y-pile was also proposed based on the assumptions of soil failure mode at the tip of Y-pile and the use of Mohr-Coulomb soil yield criterion and Vesic compressive correction coefficient with the induced stresses in the ground. Based on the comparisons with the field static load test results, it is found that the improved Terzaghi’s method gives higher ultimate capacity, while the other two methods shows good agreement with the field results.     

Adhesion coefficient of automobile tire and road surface

The adhesion coefficient of automobile tire and road surface was analyzed and the formula about it was derived.Some suggestions about highway construction,driving safety of the drivers and the judgment of the traffic accidents were presented.The results show that the adhesion coefficient is a function with the extreme value.If there is atmospheric pressure in the tire,the load of the vehicle and the degree of the coarse on the road surface is not selected properly,it will reach the least and affect the safety of the running automobile.     

Effects of stress conditions on rheological properties of granular soil in large triaxial rheology laboratory tests

In order to study the rheological properties of red stone granular soil,a series of rheological experiments were executed on large tri-axial rheological apparatus.Under 100,200 and 300 kPa confining stress conditions,the rheological tests were carried out.These experiment results showed that the stress conditions,especially the stress level were the critical influencing factors of the rheological deformation properties.Under the low stress level(S=0.1),the granular soil showed the elastic properties,and there was no obvious rheological deformation.Under the middle stress level(0.20.8) creep curves showed the non-linear viscous plastic rheological properties.Especially,under the stress level of S=1.0,the accelerated rheological phase of creep curves occurred at early time with a trend of failure.The stress level had obvious effects on the final rheological deformation of the soil sample,and the final rheological deformation increments nonlinearly increased with stress level.The final rheological deformation increment and step was little under low stress level,while it became large under high stress level,which showed the nonlinearly rheological properties of the granular soil.The confining pressure also had direct effects on final rheological deformation,and the final rheological deformation linearly increased with confining pressure increments.     

2008年我国房地产业的发展模式与市场把握

在深入市场调查、认真采集数据和科学分析研究的基础上,从我国新一年房地产业发展的"背景和环境"、"预期和责任"、"风险和影响"、"保障和创新"等方面进行阐述和论证.     

窃取商业秘密获得的专利权归商业秘密权利人所有——兼谈商业秘密构成要件和范围

中国加入WTO以后,知识产权的保护意识日益强化,作为知识产权范畴的专利权更是被人们普遍关注和重视.以"错案"为研究对象,运用商业秘密的有关理论以及保护商业秘密和专利权的有关法律制度,特别是从窃取商业秘密获得的专利权归谁所有的角度,对人民法院的判决进行了分析研究,指出了人民法院的判决是错误的,提出了窃取商业秘密获得的专利权归商业秘密权利人所有.这有利于人民法院公正司法,依法审判.     

从语气助词的角度浅析日语表达方式的特性

日语中有着十分丰富的语气助词,其虽然不具有实际的意义,然而通过语气助词,却能够流露出说话者的心情和感受,传递出不溢于言表的隐性含义,在日常的表达中扮演着十分重要的角色.从语气助词的角度,分析总结日语在表达上所具有的特性.     

Additional water use influencing strength and fluidity of recycled concrete

Through adding different additional water use,the compressive strength,splitting tensile strength and fluidity of recycled concrete of three aggregate combination forms were studied by experiment respectively.The experimental results show that with the increase of adding additional water use,the compressive strength and splitting tensile strength of recycled coarse aggregate concrete decrease,but that of recycled fine aggregate concrete and recycled all aggregate concrete increase firstly then decrease.When additional water use is added more 15% or 20% than that of basic ordinary concrete,the recycled coarse aggregate concrete and fine one can get pretty good fluidity.When it is added more 30%,the recycled all aggregate concrete has fluidity that is just satisfied.     

情趣与意象的契合——《逢雪宿芙蓉山主人》与《雪夜林边驻脚》之比较

通过分析《逢雪宿芙蓉山主人》与《雪夜林边驻脚》两诗的情趣和意象,发现两诗都采用了大致相似的意象.但由于诗人各自的文化传统的差异,在两诗中所传达的情趣却不同.然而,正是由于两诗各自在情趣与意象上的契合,才创造出了各自完美的诗境.     

关于提高企业创新能力的法律思考

在世界新科技革命推动下,知识在经济社会发展中的作用日益突出,国民财富的增长和人类生活的改善越来越有赖于知识的积累和创新。知识的积累和创新主体主要是企业,但我国企业自主创新能力薄弱已制约了我国社会经济发展。本文分析了我国企业自主创新能力的现状,探讨了欧盟及相关国家支持产业研究与创新的相关措施。构建了提高我国企业自主创新能力机制:即立法确立企业在自主创新中主体地位;大力提高对知识产权的管理、运用能力,依法加强对知识产权的保护;完善提高企业自主创新能力的法律和政策体系。     

干气密封摩擦副启停阶段摩擦特性的仿真研究

针对干气密封非稳态下摩擦特性对密封性能的影响进行研究,考虑动、静环材料属性,微凸体之间的相互作用以及摩擦热流耦合,建立了三维粗糙实体与理想光滑刚体滑动摩擦热力耦合模型。运用ANSYS软件数值模拟了摩擦热以及应力变化规律。研究发现,粗糙表面最高接触温度随滑动时间增加呈逐步上升趋势,并且温升呈 现了一定的波动性;粗糙表面的VonMises等效应力分布极其不均匀呈非线性变化;同时,还发现最大x 方向应力分量σxx 并未出现在最高接触微凸体上;在沿三维粗糙实体厚度方向存在一拉应力区,随着滑动时间的持续,拉应力区有一定程度扩大。从而说明两端面间的温升和波动性以热传导为主要影响因素,应力的变化是由于微凸体发生了弹塑性变形。研究成果为今后干气密封启停阶段特性研究以及参数优化奠定了基础。     

Linux多线程的互斥与同步控制及实践

随着计算机软硬件的发展,对计算机的执行效率的要求不断提高,多线程技术应运而生,现在已被许多操作系统所支持.介绍了多线程系统中互斥与同步机制,在Linux系统下利用信号量操作及利用pthread多线程函数编程实现多线程间的互斥与同步控制,并以生产者和消费者问题为例进行分析与实践.     

培育大学生公平正义美德的方法

公平正义是社会制度的首要价值,也是人的至上美德.公平正义美德,是公平正义原则和价值在个人思想、行为中体现出来的比较稳定的特征与倾向.培育大学生公平正义美德,是构建公平正义的和谐社会与提高大学生自身素质的需要.依据公平正义美德的形成条件,高校应在德育内容、制度建设、教育理念等方面进行改革和创新.     

中国土地利用与生态安全耦合协调研究

土地利用与区域生态安全格局紧密相关,本文在国家尺度上,选择中国2004~2014年的面板数据,将CO₂排放纳入土地利用与生态安全耦合协调评价指标体系,运用熵值法、综合评价函数和耦合协调模型测算土地利用与生态安全的耦合协调度,在ArcGIS软件支持下,分析31个省市区土地利用与生态安全耦合协调度的时空演变规律. 结果表明：（1）2004~2014年间,31省市区土地利用综合评价指数、生态安全综合评价指数、耦合协调度指数整体上升,反映我国近年来,随着土地利用程度的提高,生态安全水平向良性趋势发展;（2）在土地利用与生态安全耦合度的空间分异上,西部地区的耦合度主要处在低水平耦合阶段和拮抗阶段,中部地区多在磨合阶段,高水平耦合阶段主要是东部沿海地区,体现了区域土地利用与生态安全的耦合水平呈梯度空间分布;（3）从2004、2009和2014年的截面数据表明,近年来,我国大部分省市区土地利用与生态安全协调度属于中度协调耦合阶段的土地利用制约型,高度协调耦合区间的省市区数目减少,没有省市区处于极度协调耦合区间,说明我国各省市区土地利用与生态安全的协调发展水平还较低下. 研究区域土地利用与生态安全的耦合协调发展,有利于促进区域的土地合理、高效利用和解决生态环境问题.     

洪水灾害下管道的力学计算

为了研究流动水动力、浮力、管体以及输送介质重力、土壤地基抗力对管道的共同作用,建立洪水作用下的管道力学分析模型,选用数值分析方法和有限元方法计算了管道的应力及应变。结果表明,两种方法的计算结果较接近。依据该有限元模型,分析了洪水流速和穿越距离对管道应力及应变的影响。结果表明,当流速大于3.0 m/s时,管道应力和应变随流速的增加趋势加大;当穿越距离增加时,堤岸处管道最大应力和轴向应变逐渐增大,但增幅逐渐减小;当穿越距离小于160 m时,河流中部管道的应力和轴向应变随着穿越距离的增加而增大,当穿越距离大于160 m时,应力和轴向应变随着穿越距离的增加而略有减小。对榆⁃济线埋地悬空管道进行了安全评估,结果可知即时应力为178 MPa,悬空管道安全。     

绿色生态住宅及其发展趋势

基于住宅建设的绿色生态与可持续发展理念，结合国内外绿色生态住宅发展趋势，探讨了我国的生态住宅建设的现状、基本要求及示范工程建设，我国住宅建设的重要目标之一是全面提高居住区的综合质量，包括住宅建筑质量、住宅功能质量、住宅环境质量，绿色生态住宅是中国住宅产业发展的长远目标，为更好地引导绿色生态住宅建设，实现住宅产业的可持续发展，亟须从技术、经济、环境、能源及社会的角度进行研究，制定出一套客观、科学的评价体系和技术导则。     

N和Nb对Fe-Cr-C堆焊层组织和性能的影响

为了获得具有良好组织和性能的堆焊层,以传统Fe-Cr-C合金体系为基础,通过调节药芯焊丝配方中铌铁和氮化铁的含量配比,研究了堆焊层中Nb和N元素对堆焊层组织和力学性能的影响.利用扫描电子显微镜和光学显微镜对堆焊层的显微组织进行分析,并采用能谱仪对分析位置的元素种类和元素含量进行标注测量.采用X射线衍射仪对堆焊层的相组成进行测量,同时对堆焊层的硬度及耐磨损性能进行了研究.结果表明:当N元素的质量分数为3%,Nb元素的质量分数为10%时,堆焊层组织由马氏体、残余奥氏体、M_7C_3、NbN等相组成,此时堆焊层硬度达到最高值58.6 HRC,磨损失重达到最低值0.173 g.     

阳光与空间组织

随着现代建筑的发展,人们越发讨厌生硬与单调的人工空间,渴望富于生态与动态的自然和谐环境。利用太阳直射或漫射光线可以区分与限定空间、制造空间序列和视觉焦点,从而创造既满足人们生理与心理需要,又符合建筑功能与艺术要求的动态光空间,开辟空间组织的新设计思路,促进人们空间生活的健康发展。     

盖封密封磨损-热-应力耦合模拟与优化设计

在无油润滑工况下,密封面磨损是导致密封件性能降低及寿命丧失的关键因素. 结合有限元技术,基于修正的Archard磨损模型,建立盖封（CL）密封过程中密封件和活塞杆间的磨损-热-应力耦合数值模拟方法,分析磨损过程中密封件性能与寿命的变化规律及介质压力对密封特性的影响;基于所建立的仿真模型,采用正交试验设计法,以密封件密封面上最大接触压力降幅最小及密封件寿命最长作为优化目标,对CL密封中C形密封圈关键结构参数进行优化设计,得到最优组合方案;利用斯特林发动机活塞杆密封性能试验平台对数值模拟方法进行验证,并对磨损后CL密封接触面磨损状况进行测量,检测结果与仿真模拟结果较为一致,优化后密封件密封性能及使用寿命得到了提高.