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Syzygy Effects Studies Performed Simultaneously with Foucault Pendulums and Torsinds during the Solar Eclipses of 13 November 2012 and 10 May 2013 被引量:2
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作者 Dimitrie Olenici Alexander F. Pugach +5 位作者 Ilie Cosovanu Cezar Lesanu Jean-Bernard Deloly Danil Vorobyov Alexander Delets Stefan-Bogdan Olenici-Craciunescu 《International Journal of Astronomy and Astrophysics》 2014年第1期39-53,共15页
Several simultaneous observations are presented of Syzygy effects during two solar eclipses, performed with torsinds and Foucault pendulums. The experiments/measurements were of a simple nature, conducted in several o... Several simultaneous observations are presented of Syzygy effects during two solar eclipses, performed with torsinds and Foucault pendulums. The experiments/measurements were of a simple nature, conducted in several of places in Romania and Ukraine. It is shown that during Syzygy effects both the torsind and the Foucault pendulum exhibit specific reactions: the torsind’s disk is rotated, whereas the direction of the swing plane, the period, the eccentricity and the chirality of the ellipse of oscillation of the Foucault pendulum are all altered. We term all these perturbations “Syzygy effects” and found that they take place even when the devices are in locations where the eclipse is not visible and even when they are underground. An unusual time shifts?between the responses of the devices and the maximum phase of the eclipse is detected. The importance of simultaneous simple observations of astronomical phenomena using these two devices of fundamentally different types is emphasized. 展开更多
关键词 Paraconical pendulum Antieclipse effect Torsind
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Astral Actions on Allais’ Pendulum Apparently Inexplicable by Classical Factors: A Point of the Situation
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作者 Jean-Bernard Deloly 《Journal of Modern Physics》 2024年第9期1375-1408,共34页
1) The observation by Allais of the precession of pendulums from 1954 to 1960 highlighted regularities of astral origin an in-depth analysis of which showed that, apparently, no classical phenomenon can explain them. ... 1) The observation by Allais of the precession of pendulums from 1954 to 1960 highlighted regularities of astral origin an in-depth analysis of which showed that, apparently, no classical phenomenon can explain them. These regularities were diurnal waves whose periods are characteristic of astral influence (the main ones being 24 h and 24 h 50 min), annual and semi-annual components, and a multi-annual component of approximately 6 years, an influence of Jupiter being a very good candidate to explain it. 2) Allais had experimentally established that all these astral influences were expressed globally on the pendulum by an action tending to call back its plane of oscillation towards a direction variable in time, and which ovalized its trajectory. In 2019 the observation of 2 pendulums in Horodnic (Romania), thanks to the use of an automatic alidade, made it possible to identify the main mechanism that, very probably, acted on the pendulum to achieve this result. This perturbation model, called “linear anisotropy”, is characterized by its “coefficient of anisotropy” η, and by the azimuth of its “direction of anisotropy”. The composition of 2 linear anisotropies is always a linear anisotropy. 3) In the search for the phenomena which could be at the origin of all what precedes, the fact that they must create an ovalization immediately eliminates some of them. 4) We have calculated the values of η corresponding to the 24 h and 24 h 50 min waves both for the observations in Horodnic and the Allais observations. The order of magnitude (some 10−7) is effectively the same in both cases. 5) Mathematically, the regularities discovered may result of a new force field but also, as Allais proposes, from the creation, under the astral influences, of a local anisotropy of the medium in which the pendulum oscillates. In the first case the length of the pendulum is involved, in the second one not. The data available do not make it possible to decide. 6) The joint exploitation, in mechanics and optics, of Allais observations and of observations by other experimenters provides additional information: a) Allais, and after him several other scientists, discovered also marked anomalies in the precession of pendulums during certain eclipses, and maybe certain other syzygies. For the few eclipses for which both something was observed and sufficient data were available (one of them being a lunar eclipse for which nothing had been published until now), it was always the above perturbation model which acted on the pendulum, but sometimes with quite exceptional magnitude. b) There are quite possible links with optics. During the observation campaign of August 1958, which had implemented both two pendulums and an optical device, all the 24 h 50 min waves were almost in phase. In the precession of the Allais pendulum, in Miller’s interferometric observations in Mont Wilson, and in Esclangon’s observations in Strasbourg, a same peculiarity is found: the extrema of the annual influence are at the equinoxes, not at the solstices. 展开更多
关键词 Allais effect pendulum Lunisolar Influence Jupiter Influence Lunar and Solar Eclipses SYZYGIES SUNSPOTS Solar Cycles
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Inexplicable Multi-Annual Astral Action on the Precession of Allais Pendulum: An Influence of the Solar System (and Especially of Jupiter?)
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作者 Jean-Bernard Deloly 《Journal of Modern Physics》 CAS 2023年第6期953-988,共36页
Between 1954 and 1961, Allais conducted 6 one-month observations of the azimuth of the plane of oscillation of a pendulum installed in his laboratory. That of 1958 also implemented a second pendulum, identical to the ... Between 1954 and 1961, Allais conducted 6 one-month observations of the azimuth of the plane of oscillation of a pendulum installed in his laboratory. That of 1958 also implemented a second pendulum, identical to the first, located 6 km away in an underground quarry. Although, over these 6 years, the average azimuth of each observation, the amplitude of the 24 h 50 min and 24 h waves, as well as certain other quantities, have evolved considerably, in 1958 their values were very close to those of the second pendulum. The analysis shows that these evolutions could only result from an action external to the pendulum, that no classical phenomenon seems to be able to explain, and which appears, at least mainly, to be an astral action. The evolution of the average azimuth of the pendulum and of the amplitudes of the 24 h and 24 h 50 min components can be decomposed into a component associated with the annual revolution of the Earth around the Sun, and a multi-annual component, whose harmonic 1 has a period which was estimated to 5.74 years. An action of Jupiter is an excellent candidate to explain a large part of the multi-annual action: everything happens as if there were an important action of the modulus of its declination on the multi-annual component, and an important daily action of its hour angle on the azimuth of the pendulum. We cannot exclude an action of the solar cycle, whose period was then about 11 years. The main results were obtained by Allais himself, but this was only published in his book “The Anisotropy of Space”, and remained very little known. Starting from the raw data of Allais, the author of this article found them again, and completed them on certain points. 展开更多
关键词 Allais effect pendulum Lunisolar Influence Jupiter Influence
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Confirmation of 24 h 50 min Lunar Periodicity, Apparently Inexplicable by Classical Factors, in Precession of Allais Pendulum
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作者 Thomas Goodey Dimitrie Olenici +1 位作者 Jean-Bernard Deloly René Verreault 《Journal of Modern Physics》 CAS 2022年第12期1598-1634,共37页
During 36 days the motion of two pendulums, which were restarted every hour, was continuously recorded. 869 “runs” were thus made, providing each time the precession during the run, as well as other parameters of th... During 36 days the motion of two pendulums, which were restarted every hour, was continuously recorded. 869 “runs” were thus made, providing each time the precession during the run, as well as other parameters of the motion. Spectral analysis of precession and ellipticity revealed a lunar component of 24 h 50 min, which can only result from an astral action, through mechanisms yet to be discovered. Indeed, an analysis was carried out of the influence of all classical perturbing factors: direct or indirect action of classical gravity, temperature, Earth’s magnetic field, etc.… None of them can explain this component, given its amplitude and phase. Its amplitude excludes also an explanation by general relativity. This is consistent with a major result that Allais claimed to have obtained during each one of the six continuous one-month-long experiments he carried out from 1954 to 1960. The numerous and very precise data provided by an automatic alidade give additional information to those gathered by Allais. All that confirms all the scientific interest that there would be to resume long-duration pendulum observations on a much more important scale: continuous observations for at least 2 years, and if possible more. 展开更多
关键词 Allais effect pendulum 24 h 50 min Period Lunisolar Influence
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Link between Allais Effect and General Relativity’s Residual Arc during Solar Eclipse
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作者 Russell Bagdoo 《Journal of Modern Physics》 2020年第10期1620-1638,共19页
The purpose of this article is to establish a relation between two gravitational anomalies: one that has attracted part of the scientific community, the Allais effect that occurs during solar eclipse;the other, notice... The purpose of this article is to establish a relation between two gravitational anomalies: one that has attracted part of the scientific community, the Allais effect that occurs during solar eclipse;the other, noticed but forgotten by the whole scientific community, the General Relativity’s residual arc of the curvature of rays of light in the solar gravitational field during the same eclipse. There is a systematically observed deflection about 10% larger than the theoretical value of General Relativity, which coincides with the “eclipse effect” found by Maurice Allais, thrown aside because it upsets the established truths. These corresponding anomalies were never explained by any theories and turn out to be new gravitational physics. 展开更多
关键词 Allais effect Paraconical pendulum General Relativity Eclipse Experience PARALLAX Arc Residue Interferometry
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铁路标准桥梁典型减隔震体系响应行为与谱分析方法
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作者 管仲国 苏伟 +2 位作者 李晓波 王雨权 国巍 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期1097-1104,共8页
基于铁路标准桥梁3种典型减隔震设计体系,分析了结构的地震响应行为,重点研究了墩身质量的动力效应和减隔震体系的振型效应.结果显示:铁路标准桥梁墩身质量对桥墩的地震响应存在显著的动力效应,忽视该效应会导致墎顶位移和墎底弯矩的平... 基于铁路标准桥梁3种典型减隔震设计体系,分析了结构的地震响应行为,重点研究了墩身质量的动力效应和减隔震体系的振型效应.结果显示:铁路标准桥梁墩身质量对桥墩的地震响应存在显著的动力效应,忽视该效应会导致墎顶位移和墎底弯矩的平均相对误差约达11%~32%,对主梁的地震位移影响较小,平均相对误差不超过5%;桥墩的地震响应主要受计算方向上的前2阶振型控制,其中第2阶振型以桥墩自振形态为主,振型阻尼可偏于安全地按结构阻尼比考虑;基于2阶振型效应的SRSS组合可以较好地考虑减隔震铁路标准桥梁的墩身质量动力效应,其预测墩底弯矩平均相对误差可下降至7.5%;AASHTO规范建议的多振型反应谱法适用于铁路标准桥梁典型减隔震体系的地震响应分析. 展开更多
关键词 铁路标准桥梁 摩擦摆减隔震支座 钢阻尼器 桥墩质量动力效应 谱分析方法
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基于柔性铰链结构的大口径压电快摆镜
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作者 王强 时运来 +2 位作者 孙海超 李兴 刘伟 《压电与声光》 CAS 北大核心 2024年第1期73-78,共6页
为了解决压电作动器驱动的快速反射镜因压电作动器伸长量较小,导致快速反射镜偏转角过小的问题,该文提出了一款新型快速反射镜设计方案。采用三级杠杆式柔性铰链放大机构实现压电作动器位移的放大,采用柔性轴承作为快摆镜的运动关节实... 为了解决压电作动器驱动的快速反射镜因压电作动器伸长量较小,导致快速反射镜偏转角过小的问题,该文提出了一款新型快速反射镜设计方案。采用三级杠杆式柔性铰链放大机构实现压电作动器位移的放大,采用柔性轴承作为快摆镜的运动关节实现快摆镜的大角度定轴偏转。通过理论推导和有限元仿真对快摆镜的最大偏转角度、等效应力、谐振频率以及振型进行分析。实验结果表明,所设计的快摆镜可以实现大于2 mrad的镜面偏转,满足大范围、高精度的光束定位要求。 展开更多
关键词 柔性铰链 逆压电效应 压电作动器 大口径压电快摆镜 位移放大机构
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双摆起重机系统的预设性能自适应跟踪控制
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作者 唐鹏 刘汉忠 +2 位作者 朱晓春 田昭 万锦旗 《南京工程学院学报(自然科学版)》 2024年第2期22-30,共9页
针对塔式起重机在工程应用中因多种因素影响经常表现双摆特性问题,本文设计一种预设性能自适应跟踪控制器,在保证台车和起重臂快速定位的同时抑制吊钩和负载的摆动,且跟踪误差限制在设计的时变界内.通过李雅普诺夫方法和拉塞尔不变性原... 针对塔式起重机在工程应用中因多种因素影响经常表现双摆特性问题,本文设计一种预设性能自适应跟踪控制器,在保证台车和起重臂快速定位的同时抑制吊钩和负载的摆动,且跟踪误差限制在设计的时变界内.通过李雅普诺夫方法和拉塞尔不变性原理证明本文控制器的稳定性.与LQR、ESC控制器进行仿真对比,并对起重机搬运的连贯动作(变负载)进行测试,结果表明本文控制器具有良好的定位精度和抗摆动能力. 展开更多
关键词 李雅普诺夫函数 双摆效应 轨迹跟踪 塔式起重机
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基于摩擦摆支座的高速铁路简支梁桥减隔震效果分析
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作者 朱海龙 张永亮 +1 位作者 周友权 刘海涛 《工程抗震与加固改造》 北大核心 2024年第1期69-76,共8页
为研究摩擦摆支座在高速铁路简支箱梁桥的减隔震效果,以24、32、40m典型跨径高速铁路简支梁桥为研究对象,采用MIDAS/Civil有限元软件分别建立传统抗震体系和减隔震体系模型进行非线性动力时程分析,研究桥梁墩高、桥梁跨径和地震动峰值... 为研究摩擦摆支座在高速铁路简支箱梁桥的减隔震效果,以24、32、40m典型跨径高速铁路简支梁桥为研究对象,采用MIDAS/Civil有限元软件分别建立传统抗震体系和减隔震体系模型进行非线性动力时程分析,研究桥梁墩高、桥梁跨径和地震动峰值加速度(PGA)等因素对简支梁桥地震响应的影响。研究结果表明:桥墩墩高和截面形式对墩底内力和墩顶位移的减震效果有较大影响,但在5~20m墩高内受墩高的影响更为显著;墩高从5m增加到20m时,墩底内力减震率分别为80%、35%,墩高从25m增加到45m时,墩底内力减震率分别为46%、37%;桥梁跨径对结构减震率有一定影响,但在10%以内;PGA对墩底内力和墩顶位移的减震率总体上影响较小;墩高和PGA对FPB支座位移影响较大,PGA影响更为显著,支座位移增大倍数明显大于对应的PGA增加倍数。 展开更多
关键词 高速铁路 简支梁桥 摩擦摆支座 减隔震效果 影响因素
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基于自适应滑模控制的异轴两轮自平衡车
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作者 叶青 田杰 《计算机测量与控制》 2024年第11期169-176,共8页
对异轴两轮自平衡车(DATWSBV)进行了研究,将其简化为具有陀螺效应的倒立摆系统(IPS),采用拉格朗日方程建立非线性数学模型,并设计了滑模控制器(SMC)和自适应滑模控制器(ASMC);对无控制、SMC控制以及ASMC控制的3种模型分别进行仿真,结果... 对异轴两轮自平衡车(DATWSBV)进行了研究,将其简化为具有陀螺效应的倒立摆系统(IPS),采用拉格朗日方程建立非线性数学模型,并设计了滑模控制器(SMC)和自适应滑模控制器(ASMC);对无控制、SMC控制以及ASMC控制的3种模型分别进行仿真,结果表明,无控制的异轴两轮自平衡车仅在陀螺仪的作用下无法恢复直立和完成转向;相较于SMC,ASMC能使IPS直行受到干扰时更快地恢复直立,且能达到期望的侧倾角以实现转向;此外,在BikeSim中建立了DATWSBV的实车模型,验证了此Bikesim模型和IPS数学模型的一致性,并基于BikeSim和Matlab/Simulink的联合仿真进一步验证了ASMC的控制效果;结果表明,ASMC能够保证异轴两轮自平衡车辆的抗干扰能力和转向能力。 展开更多
关键词 异轴两轮自平衡车 陀螺效应 倒立摆 滑模控制 自适应滑模控制
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多跨连续梁拱组合体系桥梁抗震性能分析
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作者 王坤林 付旺旺 +2 位作者 席利飞 袁少洋 周俊福 《公路交通技术》 2024年第5期47-54,共8页
为了解相邻结构、行波效应和减隔震体系对多跨连续梁拱组合体系桥梁内力的影响,以某连续梁拱组合体系桥梁为实例,通过有限元软件建立抗震计算模型,并采用反应谱法和动力时程分析法对其进行地震反应分析。结果表明:1)连续梁拱组合体系桥... 为了解相邻结构、行波效应和减隔震体系对多跨连续梁拱组合体系桥梁内力的影响,以某连续梁拱组合体系桥梁为实例,通过有限元软件建立抗震计算模型,并采用反应谱法和动力时程分析法对其进行地震反应分析。结果表明:1)连续梁拱组合体系桥梁在顺桥向地震作用下2种分析方法的计算结果大致相同,前者计算结果略大于后者,反应谱法的计算结果偏于安全;2)相邻结构对过渡墩的内力影响较大,对其他墩柱的内力影响较小,建议考虑相邻结构的影响;3)考虑行波效应后,各孔控制截面的位移、弯矩有少量增大,固定墩的内力显著增大,且随着波速的增大,结构的地震响应逐渐趋于一致激励下的地震响应;4)采用摩擦摆隔震支座后,结构的内力和位移响应均大幅降低,且各墩的受力更加均匀,建议大跨径桥梁采用减隔震体系,以降低结构的地震响应。 展开更多
关键词 梁拱组合体系桥 抗震分析 反应谱法 动力时程分析法 相邻结构 行波效应 摩擦摆隔震支座
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基于霍尔效应的角度传感器的设计与研究
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作者 董宇杰 谢茂盛 +1 位作者 冯卓宏 周大进 《大学物理实验》 2024年第2期44-48,共5页
针对现有霍尔式角度传感器所存在测量精度低等问题。基于对霍尔效应原理的探究,以霍尔电压与磁场方向的关系为基础,设计了一种基于霍尔效应的角度传感器。自制了小型亥姆霍兹线圈以提供稳定磁场,将霍尔探头固定于支撑架上,通过测量霍尔... 针对现有霍尔式角度传感器所存在测量精度低等问题。基于对霍尔效应原理的探究,以霍尔电压与磁场方向的关系为基础,设计了一种基于霍尔效应的角度传感器。自制了小型亥姆霍兹线圈以提供稳定磁场,将霍尔探头固定于支撑架上,通过测量霍尔探头旋转不同角度后的霍尔电压实现角度的高精度测量,在旋转角度不大于75°的情况下,最大测量误差为0.1°。将该传感器应用于探究复摆运动,得到复摆角位移与时间关系图像,实现复摆运动状态的准确测量,所测定的摆动周期与理论值的误差仅为2.0%,证明了该装置能够实现快速响应的高精度角度测量。 展开更多
关键词 霍尔效应 亥姆霍兹线圈 角度传感器 复摆运动
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计及横向边缘效应的摆式差动电容倾角传感器输出特性
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作者 周江 王福谦 《宇航计测技术》 CSCD 2024年第4期64-71,共8页
为了研究计及极板横向边缘效应的摆式差动电容倾角传感器的输出特性,利用保角变换法和格林函数法,讨论电容式倾角传感器的电场,得到其电容量随角位移的变化关系,通过MATLAB软件绘制出该传感器输出特性曲线,并对影响该传感器输出特性的... 为了研究计及极板横向边缘效应的摆式差动电容倾角传感器的输出特性,利用保角变换法和格林函数法,讨论电容式倾角传感器的电场,得到其电容量随角位移的变化关系,通过MATLAB软件绘制出该传感器输出特性曲线,并对影响该传感器输出特性的因素做了定量分析。仿真模拟结果显示,在传感器的动极板的宽度小于静极板时,增大两极板的宽度差,再适度增大极板的间距,并减小极板直缝隙的宽度,可提高该传感器灵敏度及线性度,改善其输出特性。 展开更多
关键词 摆式差动电容倾角传感器 保角变换 格林函数法 边缘效应 输出特性
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形变超晶格的位错模型与粒子的退道效应 被引量:32
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作者 罗诗裕 周小方 +2 位作者 林钧锋 马如康 邵明珠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第5期485-489,共5页
引入位错模型讨论粒子的退道效应 .把超晶格的沟道偏折等效为位错引起的沟道弯曲 ,并对刃型位错的退道行为作了具体分析 .利用正弦平方势 ,把粒子运动方程化为具有外力矩的摆方程 ,用能量法分析了系统的相平面特征 ,导出了系统的退道系数 .
关键词 超晶格 位错模型 退道效应 沟道弯曲 摆方程
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带有状态约束的双摆效应吊车轨迹规划 被引量:27
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作者 孙宁 方勇纯 钱彧哲 《控制理论与应用》 EI CAS CSCD 北大核心 2014年第7期974-980,共7页
对于欠驱动吊车而言,已有方法大都将负载摆动视为单摆进行处理.然而当吊钩质量相比负载质量不可忽略或负载体积较大时,负载会绕吊钩产生第二级摆动,出现双摆效应,使系统的摆动特性更为复杂,欠驱动度更高,其控制更具挑战性;此外,现有方... 对于欠驱动吊车而言,已有方法大都将负载摆动视为单摆进行处理.然而当吊钩质量相比负载质量不可忽略或负载体积较大时,负载会绕吊钩产生第二级摆动,出现双摆效应,使系统的摆动特性更为复杂,欠驱动度更高,其控制更具挑战性;此外,现有方法均无法保证系统的暂态控制性能.针对这些问题,本文提出了一种基于轨迹规划的消摆定位控制方法.具体而言,本方法所规划的台车轨迹具有解析表达式,且充分考虑系统安全性(摆动幅值)及台车运动的物理约束;通过构造新颖的平坦输出信号,将施加在台车运动和两级摆动上的约束/指标转化为对平坦输出的约束,从而将轨迹规划转化为凸优化问题.该方法能够保证整个过程中系统两级摆动的角度、角速度,台车的速度、加速度、加加速度均保持在设定范围内.通过与已有方法进行仿真对比,可见本方法不仅简单易行,且在工作效率与摆动抑制方面均具有更为良好的控制性能. 展开更多
关键词 吊车 双摆效应 轨迹规划 状态约束
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形(应)变超晶格的沟道效应与系统的相平面特征 被引量:20
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作者 罗诗裕 马如康 邵明珠 《原子核物理评论》 CAS CSCD 北大核心 2002年第4期407-410,共4页
利用正弦平方势,把粒子运动方程化为具有δ力矩的摆方程.分析了无扰动系统的相平面特征,计算了扰动系统的退道效应.讨论了退道系数与晶格形变之间的关系.
关键词 沟道效应 相平面特征 摆方程 力矩 退道效应 能带结构 形变超晶格 应变超晶格 半导体 无扰动系统 带电粒子
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钟摆效应?抑或融合效应?——从新公共管理到新公共服务的价值变迁 被引量:5
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作者 刘耀东 施雪华 《晋阳学刊》 CSSCI 2010年第5期25-28,共4页
从新公共管理到新公共服务的范式转变实质上是管理主义价值到宪政主义价值的变迁。一方面,从哲学基础和主导价值来看,两大范式存在着从工具理性向价值理性的钟摆式效应,从效率、经济、效能为主导的管理主义价值到以公平、公正、民主为... 从新公共管理到新公共服务的范式转变实质上是管理主义价值到宪政主义价值的变迁。一方面,从哲学基础和主导价值来看,两大范式存在着从工具理性向价值理性的钟摆式效应,从效率、经济、效能为主导的管理主义价值到以公平、公正、民主为主导的宪政主义价值的钟摆式效应;另一方面,从二元价值的交叉与整合来看,两大范式又存在着融合式效应。公共行政既是管理问题,又是宪政问题,只有把两种认知结合起来,才能理解公共行政,进而有效地解决公共行政的现实问题。 展开更多
关键词 新公共管理 新公共服务 钟摆效应 融合效应
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摩擦摆基础隔震结构双向地震反应分析 被引量:18
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作者 王建强 管品武 李大望 《世界地震工程》 CSCD 北大核心 2005年第3期11-15,共5页
采用双向耦合力学模型模拟摩擦摆支座的双向耦合效应,对摩擦摆基础隔震结构进行了单向和双向地震反应对比分析,分析表明在双向地震作用下结构各层的加速度反应较小,隔震层的层间位移较大,而上部结构的层间位移较小,并且在双向地震作用下... 采用双向耦合力学模型模拟摩擦摆支座的双向耦合效应,对摩擦摆基础隔震结构进行了单向和双向地震反应对比分析,分析表明在双向地震作用下结构各层的加速度反应较小,隔震层的层间位移较大,而上部结构的层间位移较小,并且在双向地震作用下,支座的最大位移明显大于单向地震作用时的支座最大位移,因而应考虑双向地震作用对摩擦摆基础隔震结构地震反应和隔震支座性能的影响。 展开更多
关键词 摩擦摆 双向耦合作用 地震反应
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采用摩擦摆支座的超大跨连续梁桥隔震效果 被引量:4
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作者 张超 刘涛 +1 位作者 余立 颜学渊 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2017年第3期449-455,共7页
为了研究超大跨连续梁桥采用摩擦摆支座的隔震效果,以某主跨为240 m的七跨钢-混凝土连续梁桥为工程背景,建立桩土相互作用动力分析模型,采用非线性连接单元模拟盆式滑动支座及摩擦摆支座的非线性受力性能.非线性地震响应分析结果表明:... 为了研究超大跨连续梁桥采用摩擦摆支座的隔震效果,以某主跨为240 m的七跨钢-混凝土连续梁桥为工程背景,建立桩土相互作用动力分析模型,采用非线性连接单元模拟盆式滑动支座及摩擦摆支座的非线性受力性能.非线性地震响应分析结果表明:采用传统抗震体系时,超大跨连续梁桥的固定墩及其桩基础的内力需求非常大;采用摩擦摆支座的隔震体系可以减少固定墩及其桩基础内力约40%,并显著改善其他桥墩的地震力分配.摩擦摆支座对超大跨连续梁桥的减震机理主要体现为:延长结构自振周期、减小固定墩有效振动质量、改变地震力传递途径、增强附属装置耗能,从而显著地改善了超大跨连续梁桥的地震响应. 展开更多
关键词 超大跨度 连续梁桥 摩擦摆支座 隔震效果
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利用解析法计算倒垂孔有效孔径及中心的改进方法 被引量:2
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作者 金鑫 饶学宾 保其长 《水力发电》 北大核心 2010年第10期96-100,共5页
解析法在计算倒垂孔有效孔径及中心时逐步受到重视。通过对倒垂孔有效孔径的求解过程进行几何分析和理论归纳,提出一种改进的计算倒垂孔有效孔径和中心的解析方法,并给出基于Visual Basic计算机语言的算法框图。根据该方法开发了一套实... 解析法在计算倒垂孔有效孔径及中心时逐步受到重视。通过对倒垂孔有效孔径的求解过程进行几何分析和理论归纳,提出一种改进的计算倒垂孔有效孔径和中心的解析方法,并给出基于Visual Basic计算机语言的算法框图。根据该方法开发了一套实用性强的计算程序,可以快速、精确地计算有效孔径和中心,并已在工程实际应用中得到验证,取得了良好效果。 展开更多
关键词 倒垂孔 有效孔径 解析法 VISUAL Basic
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