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脊加载环板行波管高频特性的研究 被引量:1
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作者 宫玉彬 王文祥 +2 位作者 魏彦玉 孙嘉鸿 刘盛纲 《电子学报》 EI CAS CSCD 北大核心 2000年第3期64-68,共5页
脊加载环板行波管是一种频带相对较宽的大功率行波管 ,本文用场匹配和变分原理相结合的方法 ,研究了脊加载环板慢波结构的导波特性及这种行波管的小信号、大信号特性 ,讨论了结构的几何尺寸及电子注参量对慢波的传播特性、小信号增益及... 脊加载环板行波管是一种频带相对较宽的大功率行波管 ,本文用场匹配和变分原理相结合的方法 ,研究了脊加载环板慢波结构的导波特性及这种行波管的小信号、大信号特性 ,讨论了结构的几何尺寸及电子注参量对慢波的传播特性、小信号增益及注 波互作用非线性效应的影响 .本文的结果将为脊加载环板行波管的设计提供理论基础 . 展开更多
关键词 加载环 行波管 慢波系统 高频特性
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介质加载环板慢波结构高频特性研究 被引量:1
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作者 殷海荣 宫玉彬 +3 位作者 魏彦玉 黄民智 路志刚 王文祥 《强激光与粒子束》 EI CAS CSCD 北大核心 2006年第9期1553-1558,共6页
提出了一种适用于环板结构的计算等效相对介电常数的方法,利用变分法导出了介质加载环板慢波结构的色散方程和耦合阻抗表达式。计算结果表明,介质加载能够有效降低环板慢波结构的工作电压。计算结果与CST-MWS的模拟结果吻合良好,说明所... 提出了一种适用于环板结构的计算等效相对介电常数的方法,利用变分法导出了介质加载环板慢波结构的色散方程和耦合阻抗表达式。计算结果表明,介质加载能够有效降低环板慢波结构的工作电压。计算结果与CST-MWS的模拟结果吻合良好,说明所提出的计算等效相对介电常数的方法和计算色散方程的方法对环板慢波结构是切实可行的。 展开更多
关键词 介质加载环板慢波结构 色散方程 等效相对介电常数 耦合阻抗
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应用交指电容加载环谐振器的微带带阻滤波器 被引量:4
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作者 彭毅 章文勋 《电波科学学报》 EI CSCD 北大核心 2009年第5期909-913,共5页
提出了一种交指电容加载环谐振器(IDCLLR),与同尺寸的开环谐振器(SRR)相比,具有更多的设计参数、更低的谐振频率和更大的动态范围,因而使得设计更加灵活、也更适于器件小型化。随后提出两种基于IDCLLR的亚波长微带带阻滤波器结构:第一... 提出了一种交指电容加载环谐振器(IDCLLR),与同尺寸的开环谐振器(SRR)相比,具有更多的设计参数、更低的谐振频率和更大的动态范围,因而使得设计更加灵活、也更适于器件小型化。随后提出两种基于IDCLLR的亚波长微带带阻滤波器结构:第一种是由一对IDCLLR磁耦合到50欧姆微带传输线构成的滤波器,获得0.39%(-10 dB)的窄的阻带;第二种是由一个IDCLLR磁耦合到U形微带传输线中构成的滤波器,由于增强耦合而获得2.4%的较宽且深的阻带。文中给出了它们的全波仿真和测试结果。 展开更多
关键词 人工电磁材料 交指电容加载环谐振器 微带带阻滤波器
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基于改进的方环枝节加载谐振器的三通带滤波器
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作者 高明华 郭晓飞 +2 位作者 杨根红 王忠磊 彭阳 《江西师范大学学报(自然科学版)》 CAS 北大核心 2016年第3期303-306,共4页
基于改进型的方形环枝节加载多模谐振器,设计了一款可用于LTE系统和WLAN系统的三通带滤波器.与传统的方形环枝节加载多模谐振器相比,通过引入阶跃阻抗谐振器的概念,使滤波器的设计具有更高的自由度.实验结果表明:该滤波器的工作频段可... 基于改进型的方形环枝节加载多模谐振器,设计了一款可用于LTE系统和WLAN系统的三通带滤波器.与传统的方形环枝节加载多模谐振器相比,通过引入阶跃阻抗谐振器的概念,使滤波器的设计具有更高的自由度.实验结果表明:该滤波器的工作频段可以覆盖LTE和WLAN频段,有较高的实用性. 展开更多
关键词 三通带滤波器 改进型的方形枝节谐振器 阶跃阻抗谐振器 奇偶模理论
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多功能加载装置的研制和应用 被引量:10
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作者 张禁 张文元 张耀春 《工业建筑》 CSCD 北大核心 2004年第3期40-43,共4页
为适应多杆件平面汇交节点工作性能的试验研究需要 ,研制了由加载环、钢拉杆和千斤顶等设备组成的多功能加载装置。该装置的最大加载吨位为 4 0 0 0kN ,试件的长度可达 3 5m。除介绍了加载装置的设计和构造外 ,还通过试验验证了加载装... 为适应多杆件平面汇交节点工作性能的试验研究需要 ,研制了由加载环、钢拉杆和千斤顶等设备组成的多功能加载装置。该装置的最大加载吨位为 4 0 0 0kN ,试件的长度可达 3 5m。除介绍了加载装置的设计和构造外 ,还通过试验验证了加载装置的可靠性 。 展开更多
关键词 多功能试验装置 加载环 钢拉杆 钢结构 工字钢
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一种基于新型组合加载方式的大频差三频段蝶形天线
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作者 李兵舰 张租存 《现代雷达》 CSCD 北大核心 2019年第4期67-69,74,共4页
将分形技术和槽加载技术相结合,文中提出了一种基于新型组合加载方式的大频差三频段蝶形天线,其加载方式为开口圆环缝隙和寄生分形多三角形结构(TSFPE)的组合加载。新型天线可同时工作于X/Ku/Ka三个频段,其中,蝶形天线两三角形臂控制X频... 将分形技术和槽加载技术相结合,文中提出了一种基于新型组合加载方式的大频差三频段蝶形天线,其加载方式为开口圆环缝隙和寄生分形多三角形结构(TSFPE)的组合加载。新型天线可同时工作于X/Ku/Ka三个频段,其中,蝶形天线两三角形臂控制X频段,加载于三角形臂上的开口圆环缝隙和位于蝶形天线三角形臂顶点位置附近的TSFPE分别控制Ku和Ka频段。新型组合加载方式充分合理地利用了天线各部分的空间,减小了各频段之间的互相影响,确保了每个频段的性能。验证了新型组合加载方式的可行性,丰富了多频天线的结构形式和种类。 展开更多
关键词 多频段 寄生分形多三角形 缝隙 蝶形天线
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毫米波星载多频段多极化共馈天线系统 被引量:1
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作者 王宏建 郝齐焱 +4 位作者 刘世华 易敏 陈雪 刘广 赵鑫 《北京理工大学学报》 EI CAS CSCD 北大核心 2015年第3期290-293,298,共5页
天线工作频率为18.7,23.8GHz和37.0GHz,采用环加载波纹喇叭使工作带宽达到2倍,新型结构的超宽带正交模耦合器实现双极化信号的提取,微波多工器完成3个频段信号的有效分离.18.7GHz信号交叉极化电平和副瓣电平分别为-32.6,-21.0dB,23.8GH... 天线工作频率为18.7,23.8GHz和37.0GHz,采用环加载波纹喇叭使工作带宽达到2倍,新型结构的超宽带正交模耦合器实现双极化信号的提取,微波多工器完成3个频段信号的有效分离.18.7GHz信号交叉极化电平和副瓣电平分别为-32.6,-21.0dB,23.8GHz信号交叉极化电平和副瓣电平分别为-31.6,-30.0dB,37.0GHz信号交叉极化电平和副瓣电平分别为-25.0,-30.0dB.仿真结果表明馈源系统适合星载天线设计,馈源结构更加紧凑,实能现对同一目标的多频率复用观测. 展开更多
关键词 天线 波纹喇叭 正交模耦合器 微波多工器 交叉极化
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一种基于环缝高次模的双频段大频差天线 被引量:2
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作者 张祖存 邓小乔 吴素云 《微波学报》 CSCD 北大核心 2016年第4期6-9,共4页
提出了一种基于加载环缝高次模的新型双频段大频差天线,其具体结构为在蝶形天线两臂上对称地加载一对闭合圆环缝隙。常规的环缝加载方式为开口环缝加载,该加载方式环缝工作在基模;而本文提出的闭合环缝加载,可使环缝工作在高次模。加载... 提出了一种基于加载环缝高次模的新型双频段大频差天线,其具体结构为在蝶形天线两臂上对称地加载一对闭合圆环缝隙。常规的环缝加载方式为开口环缝加载,该加载方式环缝工作在基模;而本文提出的闭合环缝加载,可使环缝工作在高次模。加载环缝高次模的利用,可使天线在实现大频差的同时确保其在高频段的性能。所研制的天线可实现超过3∶1的大频差,仿真和实测结果表明:天线在两个频段都具有良好的性能。新型天线结构的研制成功丰富了多频天线的种类,为实现大频差天线提供了一种新的思路和方法。 展开更多
关键词 双频段 大频差 蝶形天线
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Effects of loading waveforms on rock damage using particle simulation method 被引量:5
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作者 XIA Ming GONG Feng-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第7期1755-1765,共11页
The particle simulation method is used to study the effects of loading waveforms (i.e. square, sinusoidal and triangle waveforms) on rock damage at mesoscopic scale. Then some influencing factors on rock damage at t... The particle simulation method is used to study the effects of loading waveforms (i.e. square, sinusoidal and triangle waveforms) on rock damage at mesoscopic scale. Then some influencing factors on rock damage at the mesoscopic scale, such as loading frequency, stress amplitude, mean stress, confining pressure and loading sequence, are also investigated with sinusoidal waveform in detail. The related numerical results have demonstrated that: 1) the loading waveform has a certain effect on rock failure processes. The square waveform has the most damage within these waveforms, while the triangle waveform has less damage than sinusoidal waveform. In each cycle, the number of microscopic cracks increases in the loading stage, while it keeps nearly constant in the unloading stage. 2) The loading frequency, stress amplitude, mean stress, confining pressure and loading sequence have considerable effects on rock damage subjected to cyclic loading. The higher the loading frequency, stress amplitude and mean stress, the greater the damage the rock accumulated; in contrast, the lower the confining pressure, the greater the damage the rock has accumulated. 3) There is a threshold value of mean stress and stress amplitude, below which no further damage accumulated after the first few cycle loadings. 4) The high-to-low loading sequence has more damage than the low-to-high loading sequence, suggesting that the rock damage is loading-path dependent. 展开更多
关键词 rock damage failure process crack initiation and propagation loading waveform cycle loading particle simulation method
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Selective hydrogenation of phenol to cyclohexanone in water over Pd catalysts supported on Amberlyst-45 被引量:5
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作者 赵梦思 石娟娟 侯昭胤 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期234-239,共6页
A series of Pd catalysts were prepared on different supports(Fe2O3,SiO2,ZnO,MgO,Al2O3,carbon,and Amberlyst-45) and used in the selective hydrogenation of phenol to cyclohexanone in water.The Amberlyst-45 supported P... A series of Pd catalysts were prepared on different supports(Fe2O3,SiO2,ZnO,MgO,Al2O3,carbon,and Amberlyst-45) and used in the selective hydrogenation of phenol to cyclohexanone in water.The Amberlyst-45 supported Pd catalyst(Pd/A-45) was highly active and selective under mild conditions(40-100 ℃,0.2-1 MPa),giving a selectivity of cyclohexanone higher than 89%even at complete conversion of phenol.Experiments with different Pd loadings(or different particle sizes) confirmed that the formation of cyclohexanone was a structure sensitive reaction,and Pd particles of12-14 nm on Amberlyst-45 gave better selectivity and stability. 展开更多
关键词 PHENOL HYDROGENATION CYCLOHEXANONE PALLADIUM Amberlyst-45 resin Supported catalyst
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A nonlinear rheological damage model of hard rock 被引量:11
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作者 HU Bo YANG Sheng-qi XU Peng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第7期1665-1677,共13页
By adopting cyclic increment loading and unloading method, time-independent and time-dependent strains can be separated. It is more reasonable to describe the reversible and the irreversible deformations of sample sep... By adopting cyclic increment loading and unloading method, time-independent and time-dependent strains can be separated. It is more reasonable to describe the reversible and the irreversible deformations of sample separately during creep process. A nonlinear elastic-visco-plastic rheological model is presented to characterize the time-based deformational behavior of hard rock. Specifically, a spring element is used to describe reversible instantaneous elastic deformation. A reversible nonlinear visco-elastic (RNVE) model is developed to characterize recoverable visco-elastic response. A combined model, which contains a fractional derivative dashpot in series with another Hook’s body, and a St. Venant body in parallel with them, is proposed to describe irreversible visco-plastic deformation. Furthermore, a three-stage damage equation based on strain energy is developed in the visco-plastic portion and then nonlinear elastic-visco-plastic rheological damage model is established to explain the trimodal creep response of hard rock. Finally, the proposed model is validated by a laboratory triaxial rheological experiment. Comparing with theoretical and experimental results, this rheological damage model characterizes well the reversible and irreversible deformations of the sample, especially the tertiary creep behavior. 展开更多
关键词 Hard rock multi-step loading and unloading cycles NONLINEAR DAMAGE rheological model
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Dilatancy and liquefaction behaviour of clean sand at wide range of confining stresses 被引量:5
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作者 GU Lin-lin WANG Zhen +1 位作者 HOSOYA Asa-hiro ZHANG Feng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第8期2394-2407,共14页
The state of clean sand was mainly dependent on its void ratio(density)and confining stress that greatly influenced the mechanical behavior(compression,dilatancy and liquefaction)of clean sand.Confirming whether the c... The state of clean sand was mainly dependent on its void ratio(density)and confining stress that greatly influenced the mechanical behavior(compression,dilatancy and liquefaction)of clean sand.Confirming whether the confining stress was a state variable of sand required precise element tests at different confining stress,especially the tests under very low confining stress whose test data were very limited.In this study,static-dynamic characteristics of clean sand was comprehensively investigated by a unified test program under low and normal confining stress ranging from 5 to 98 kPa,under monotonic/cyclic and drained/undrained conditions,together with the literature available data under confining stress of 1.0 to 3.0 MPa.For monotonic loading tests,the contraction/dilation phase transition was observed for loose sand at low confining stress,and dilatancy angles were stress-dependent.In addition,the liquefaction resistance was observed to increase with reducing of confining stress,and the axial strain varied from compressive to dilative when confining stress increased.Special attention was also paid to the enhancement effect of membrane,and it was observed that its influence on the test results was limited.In addition,the experimental results were proved reliable by reproducibility. 展开更多
关键词 void ratio confining stress monotonic/cyclic loading drained/undrained triaxial test state variable of sand
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Effects of earthquake on damage evolution and failure mechanism of key rock pillars in underground engineering 被引量:2
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作者 WANG Hai-quan ZHOU Zi-long +1 位作者 LI Jun-ping ZHAO Yuan 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第9期3125-3139,共15页
Rock pillar is the key supporting component in underground engineering.During an earthquake,the key rock pillar must bear both the seismic load and the load transferred from other damaged pillars.This paper attempts t... Rock pillar is the key supporting component in underground engineering.During an earthquake,the key rock pillar must bear both the seismic load and the load transferred from other damaged pillars.This paper attempts to reveal the influence of the mainshock on damage evolution and failure characteristic of the key rock pillar during aftershocks by cyclic loading test of marble.Four levels of pre-damage stress(i.e.,10,30,50 and 70 MPa)in the first cycle were used to simulate the mainshock damage,and then cyclic stress with the same amplitude(namely 10 MPa)was conducted in the subsequent cycles to simulate the aftershock until rock failure.The results indicate that the presence of pre-damage has an obvious weakening effect on the bearing capacity and deformation resistance of rock materials during the aftershock process.Besides,the increase of pre-damage significantly changes the final failure pattern of the key rock pillar,and leads to an increase in the proportion of small-scale rock fragments.This study may contribute to understanding the seismic capacity of the unreinforced rock pillar during mainshock-aftershock seismic sequences and to optimizing the design of the key rock pillar in underground engineering. 展开更多
关键词 mainshock damage damage evolution failure mechanism damaged rock cyclic loading
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Preparation of porous Ti35Nb alloy and its mechanical properties under monotonic and cyclic loading 被引量:2
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作者 林建国 张云飞 马蓦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第3期390-394,共5页
The Ti-35%Nb(mass fraction) foams were prepared by a powder metallurgy method,and the microstructure and the mechanical properties of the foams under monotonic and cyclic loading were investigated.The microstructure o... The Ti-35%Nb(mass fraction) foams were prepared by a powder metallurgy method,and the microstructure and the mechanical properties of the foams under monotonic and cyclic loading were investigated.The microstructure of the foams mainly consists of β phase,and the foams exhibit the homogenous pore distribution with the average pore size of 252 μm.The foams with 66% porosity show a typical stress-strain curve of the open-cell foams,and the plateau stress is about 56 MPa.The fatigue strength of the foam is 15.12 MPa at 107 cycles.The fractographic analysis of the foams reveals that the cracks nucleate within the struts and grow in a fatigue mechanism,resulting in the acceleration of the fatigue damage of the foams. 展开更多
关键词 Ti35Nb foams fatigue properties powder metallurgy
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Analysis on seismic performance of a new type of joint in steel structures 被引量:1
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作者 Li Xiaodong Ma Guangtian Yan Yinji 《Journal of Southeast University(English Edition)》 EI CAS 2021年第3期290-298,共9页
To examine the seismic performance of a newly fabricated weakened joint at the beam end position,four groups of energy-consuming steel plates with different weakening depths and thicknesses were subjected to horizonta... To examine the seismic performance of a newly fabricated weakened joint at the beam end position,four groups of energy-consuming steel plates with different weakening depths and thicknesses were subjected to horizontal cyclic reciprocating loading tests on beam ends.The tests were designed to evaluate the beams'hysteresis curve,skeleton curve,bearing capacity degradation curve,stiffness degradation curve,and ductility and the nodes'energy dissipation capacity.The test results show that a newly fabricated joint will not undergo brittle damage when the beam-column joint is welded at a displacement of 105 mm.Thus,the hysteresis curve will show an inverse S shape,and an obvious slip phenomenon will occur,which is mainly due to splicing.The diameter of the bolt connecting the slab to the beam flange is slightly smaller than the aperture.Due to the existence of slippage,the skeleton curve has no evident yield point.The joint ductility coefficient is less than 3.0,and the initial rotational stiffness of the joint is also small.The buckling of the splicing panel causes a rapid decrease in the joint bearing capacity.The main approaches,appropriately reducing the weakening depth and increasing the thickness of the splicing plate,can delay the occurrence of buckling and improve the ductility of the joint. 展开更多
关键词 steel structure energy-dissipating members weakened joint seismic performance cyclic loading tests
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一种K波段波纹馈源的结构工艺研究
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作者 杨邦宏 程海平 +1 位作者 李德义 刘晶晶 《电子世界》 2018年第6期188-189,共2页
为了满足一种高带宽K波段波纹馈源的电性能指标,针对具有环加载槽馈源加工难度大、成型复杂的特点,本文介绍了一种K波段馈源的结构工艺方法。通过分片加工、叠片套装的成型方法,降低馈源的加工难度,并解决了环加载槽的加工问题。通过对... 为了满足一种高带宽K波段波纹馈源的电性能指标,针对具有环加载槽馈源加工难度大、成型复杂的特点,本文介绍了一种K波段馈源的结构工艺方法。通过分片加工、叠片套装的成型方法,降低馈源的加工难度,并解决了环加载槽的加工问题。通过对K波段波纹喇叭的测试,馈源基本满足预期指标要求,验证了馈源结构工艺设计的合理性。 展开更多
关键词 馈源喇叭 K波段 叠片套装
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Load compensation research on twicetension for loop anchor cable of inner lining in Yellow River-crossing tunnel 被引量:3
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作者 Yin Juan Cao Shengrong +1 位作者 Qin Gan Yang Fan 《Engineering Sciences》 EI 2014年第1期77-86,共10页
The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loo... The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loop anchorage prestressing loss(PL) values of inner lining(IL)in Yellow River-crossing tunnel under two anchorage systems,including twice- tension anchorage system and HM(Chinese transliteration is huanmao)anchorage system,are introduced. The software ANSYS is selected to realize the three-dimensional(3D) finite element modeling to accomplish simulation and calculation works under the two anchorage systems,respectively. Stress processes of IL under the two working conditions,of which one is completed cable tensioning(CCT) and the other is water in the tunnel with the designed water pressure(DWP),are contrasted and analyzed. Impacts of prestressing forces of anchor cables on structural safety under the two anchorage systems are contrasted. The calculation results show that the twice-tension anchorage system can reduce PL effectively and then increase prestresses of wall concrete(WC). Meanwhile,the anchorage system has the advantages of improving security and stability of tunnel structure,reducing project costs and saving steel consumption. The research work is available to related design and construction of anchor cable,and is worthy of promotion and application. 展开更多
关键词 loop anchorage prestressing loss twice-tension load compensation nonlinear finite element Yellow River-crossing tunnel
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4330和17-4PH钢在HCl溶液中的应力腐蚀行为 被引量:1
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作者 刘震 高安阳 +3 位作者 赵士光 潘爱胜 江济 邢学强 《安徽工业大学学报(自然科学版)》 CAS 2020年第4期314-320,共7页
对石油压裂泵阀箱用4330和17-4PH钢进行C环应力腐蚀试验,研究4330和17-4PH钢在质量分数为20%HCl溶液中的应力腐蚀性能,采用Abaqus有限元软件计算模拟C环应力分布,验证恒位移加载后C环环向中心位置可产生的最大应力。结果表明:4330和17-... 对石油压裂泵阀箱用4330和17-4PH钢进行C环应力腐蚀试验,研究4330和17-4PH钢在质量分数为20%HCl溶液中的应力腐蚀性能,采用Abaqus有限元软件计算模拟C环应力分布,验证恒位移加载后C环环向中心位置可产生的最大应力。结果表明:4330和17-4PH钢在质量分数为20%HCl溶液、加载应力120 MPa的环境中具较好的抗应力腐蚀性能,能满足工件300 h不产生应力腐蚀裂纹的工作要求;两种钢应力腐蚀行为均表现为全面腐蚀,17-4PH钢中低C和高Cr、Ni、Cu含量是导致其比4330钢具更优抗应力腐蚀能力的关键因素;将腐蚀应力提高到400 MPa时,17-4PH钢同样展现较好的抗预制裂纹扩展能力。 展开更多
关键词 4330钢 17-4PH钢 C应力 应力腐蚀行为
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Static compressive properties and damage constitutive model of rubber cement mortar with dry-and wet-curing conditions 被引量:1
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作者 YANG Rong-zhou XU Ying +1 位作者 CHEN Pei-yuan GONG Jiu 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第7期2158-2178,共21页
To investigate the static compressive properties and mechanical damage evolution of rubber cement-based materials(RCBMs) with dry-and wet-curing conditions, uniaxial compression and cyclic loading-unloading tests were... To investigate the static compressive properties and mechanical damage evolution of rubber cement-based materials(RCBMs) with dry-and wet-curing conditions, uniaxial compression and cyclic loading-unloading tests were carried out on rubber cement mortar(RCM). The mechanical properties of the uniaxial compression specimens cured at 95%(wet-curing) and 50%(dry-curing) relative humidities and cyclic loading-unloading specimens cured at wet-curing were analyzed. Under uniaxial compression, the peak stress loss ratio is higher for dry-curing than for wet-curing. The peak strain decreases with the increase of rubber content, and the peak strain increases with the decrease of curing humidity. Under cyclic loading-unloading, the variation trends of residual strain differences of the normal cement mortar and RCM at each cyclic level with the number of cycles are basically the same, but the failure modes are different. The analysis of the internal mesostructure by a scanning electron microscope(SEM) shows that initial damage is further enhanced by reducing curing humidity and adding rubber aggregate. The damage constitutive model based on strain equivalence principle and statistical theories was used to describe the uniaxial compression characteristics of RCM, and the law of mechanical damage evolution was predicted. 展开更多
关键词 curing humidity rubber cement mortar uniaxial compression cyclic loading-unloading mesoscopic damage constitutive model
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The Life Predictions in Whole Process Realized with Different Variables and Conventional Materials Constants for Elastic-Plastic Materials Behaviors under Unsymmetrical Cycle Loading 被引量:1
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作者 Yangui Yu 《Journal of Mechanics Engineering and Automation》 2015年第4期241-250,共10页
Author researches a lot of the mathematical models and the related conventional material constants in the traditional and the modem mechanics; to adopt two types of variables a and D, for the fatigue-damage-fracture b... Author researches a lot of the mathematical models and the related conventional material constants in the traditional and the modem mechanics; to adopt two types of variables a and D, for the fatigue-damage-fracture behaviors to elastic-plastic steels contained flaws, to put forward several calculation models, which are the driving force and the life prediction expressions at each stage and in whole process; for the key parameters .A1 and ,A2 in two stages, there are functional relation with other conventional material constants σF,m1 and M2,λ2, they are defined as the new calculable comprehensive material constants, and indicate their physical and geometrical meanings. In addition, for conversion methods between two types of variables, relevant calculating example is provided. Thereby, make a linking between the fracture mechanics and the damage mechanics, communicating their relationships. This works for saving man powers and funds on fatigue-damage-fracture testing that will be having practical significance. 展开更多
关键词 Life in whole process variables of two types driving force elastic-plastic materials conventional material constants.
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