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二○一六年度索阅申请表
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《测控技术》 CSCD 2016年第1期50-,共1页
为使《测控技术》更好地为科研生产、经营管理和教学服务,减少不必要的损失,尤其是把因工作变动,迁址等因素造成的浪费减少到最低,现对"《测控技术》读者关系数据库"的赠阅名单进行重新登记。请愿继续获取《测控技术》的热心... 为使《测控技术》更好地为科研生产、经营管理和教学服务,减少不必要的损失,尤其是把因工作变动,迁址等因素造成的浪费减少到最低,现对"《测控技术》读者关系数据库"的赠阅名单进行重新登记。请愿继续获取《测控技术》的热心读者认真填写下表,并在1个月内寄回我社(通信地址见背面),即可不定期获得增刊。 展开更多
关键词 关系数据库 工作变动 度索 经营管理 铝氧
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丰都长江大桥悬索桥索股矢度调整技术 被引量:1
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作者 曾东明 《桥梁建设》 EI CSCD 北大核心 1997年第1期58-59,共2页
悬索桥的大缆是承重结构,大缆矢度直接影响到全桥线性。本文介绍了丰都悬索桥矢度调整技术,该技术简便易行。
关键词 股失 调整 丰都长江大桥
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寒区高强钢丝索体内外温度相关性的研究
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作者 刘兴国 陶成云 黄巍 《山西建筑》 2023年第10期1-4,共4页
为解决高寒地区高强钢丝索体内部温度测试问题,选取三跨系杆拱桥中吊杆进行温度测试。基于现场实测数据,采用相关性理论确定吊杆内外温度间的关系,建立“吊杆钢丝温度-防护罩表面温度-有效距离”的回归模型,从而实现间接测试吊杆内部钢... 为解决高寒地区高强钢丝索体内部温度测试问题,选取三跨系杆拱桥中吊杆进行温度测试。基于现场实测数据,采用相关性理论确定吊杆内外温度间的关系,建立“吊杆钢丝温度-防护罩表面温度-有效距离”的回归模型,从而实现间接测试吊杆内部钢丝温度,得出以下结论:吊杆横断面径向温度呈非线性分布,且吊杆横断面各测点温度及温度梯度均表现出随时间呈周期为24h的波浪状曲线变化。建立了吊杆内外温度与有效距离的关系函数。吊杆横断面中心与R/2处钢丝预估与实测最大温差分别为0.6℃和0.7℃,说明该函数可有效解决吊杆内部温度的测试问题,为后续吊杆索力中温度的测试及修正提供参考和解决办法。 展开更多
关键词 桥梁吊杆 体温 测试 多元回归模型
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An Adaptive Spectral Conjugate Gradient Method with Restart Strategy
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作者 Zhou Jincheng Jiang Meixuan +2 位作者 Zhong Zining Wu Yanqiang Shao Hu 《数学理论与应用》 2024年第3期106-118,共13页
As a generalization of the two-term conjugate gradient method(CGM),the spectral CGM is one of the effective methods for solving unconstrained optimization.In this paper,we enhance the JJSL conjugate parameter,initiall... As a generalization of the two-term conjugate gradient method(CGM),the spectral CGM is one of the effective methods for solving unconstrained optimization.In this paper,we enhance the JJSL conjugate parameter,initially proposed by Jiang et al.(Computational and Applied Mathematics,2021,40:174),through the utilization of a convex combination technique.And this improvement allows for an adaptive search direction by integrating a newly constructed spectral gradient-type restart strategy.Then,we develop a new spectral CGM by employing an inexact line search to determine the step size.With the application of the weak Wolfe line search,we establish the sufficient descent property of the proposed search direction.Moreover,under general assumptions,including the employment of the strong Wolfe line search for step size calculation,we demonstrate the global convergence of our new algorithm.Finally,the given unconstrained optimization test results show that the new algorithm is effective. 展开更多
关键词 Unconstrained optimization Spectral conjugate gradient method Restart strategy Inexact line search Global convergence
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IMPROVED ACO SCHEDULING ALGORITHM BASED ON FLEXIBLE PROCESS 被引量:3
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作者 冷晟 魏孝斌 张文艺 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期154-160,共7页
An improved ant colony optimization (ACO) algorithm is utilized in cell scheduling of the flexible manufaturing process for considering the instrument constraint, manufacturing cost and time. Firstly, the initial we... An improved ant colony optimization (ACO) algorithm is utilized in cell scheduling of the flexible manufaturing process for considering the instrument constraint, manufacturing cost and time. Firstly, the initial weighted directional diagram is set up. Secondly, the algorithm based on the dynamic pheromone updating ensures the quick convergence and the optimal solution, thus improving the feasibility and the stability of the schedule system. Aiming at reducing collaboration with external partners, decreasing the total cost and balancing the production process, the algorithm is efficient in supporting the management process of the manufacturing cell and in strengthening the information arrangement capabitity of the scheduling system. Finally, experimental results of the improved algorithm are compared with those of other algorithms. 展开更多
关键词 manufacturing cell cell scheduling ACO PHEROMONE
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纳米氧化镁制备和表面改性研究 被引量:5
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作者 胡章文 郑龙金 《安徽工程科技学院学报(自然科学版)》 2006年第4期4-7,共4页
以MgCl2.6H2O和NH3.H2O为原料,乙醇和吐温80为分散剂,采用均匀沉淀法制备氢氧化镁,经水洗、醇洗、干燥、煅烧得到纳米氧化镁粉体。实验确定制备纳米氧化镁的工艺条件为:反应配比MgCl2.6H2O∶NH3.H2O(摩尔比)为1∶2,反应温度45℃,反应时... 以MgCl2.6H2O和NH3.H2O为原料,乙醇和吐温80为分散剂,采用均匀沉淀法制备氢氧化镁,经水洗、醇洗、干燥、煅烧得到纳米氧化镁粉体。实验确定制备纳米氧化镁的工艺条件为:反应配比MgCl2.6H2O∶NH3.H2O(摩尔比)为1∶2,反应温度45℃,反应时间40 min,陈化时间2 h,氢氧化镁在900℃下煅烧3 h。以亲油化度为考察指标,通过单因子实验和正交实验,确定了纳米氧化镁表面改性的最佳工艺条件为:硬脂酸0.02 g,改性温度80℃,改性时间2 h.在优化条件下,改性后的纳米氧化镁的亲油化度达到27.7%.用透射电镜(TEM)对改性前后的纳米氧化镁粉体进行了表征,TEM表明所制备的样品为纳米级,改性前后氧化镁粒子尺寸基本没有变化,但改性后的纳米氧化镁分散性明显变好. 展开更多
关键词 纳米氧化镁 表面改性 油化
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Damage warning of suspension bridges based on neural networks under changing temperature conditions 被引量:2
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作者 丁幼亮 李爱群 耿方方 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期586-590,共5页
This paper aims at successive structural damage detection of long-span bridges under changing temperature conditions.First,the frequency-temperature correlation models of bridges are formulated by means of artificial ... This paper aims at successive structural damage detection of long-span bridges under changing temperature conditions.First,the frequency-temperature correlation models of bridges are formulated by means of artificial neural network techniques to eliminate the temperature effects on the measured modal frequencies.Then,the measured modal frequencies under various temperatures are normalized to a reference temperature,based on which the auto-associative network is trained to monitor signal damage occurrences by means of neural-network-based novelty detection techniques.The effectiveness of the proposed approach is examined in the Runyang Suspension Bridge using 236-day health monitoring data.The results reveal that the seasonal change of environmental temperature accounts for variations in the measured modal frequencies with averaged variances of 2.0%.And the approach exhibits good capability for detecting the damage-induced 0.1% variance of modal frequencies and it is suitable for online condition monitoring of suspension bridges. 展开更多
关键词 structural damage detection modal frequency temperature neural network suspension bridge
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Extraction of cable forces due to dead load in cable-stayed bridges under random vehicle loads 被引量:6
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作者 刘小玲 黄侨 +2 位作者 任远 樊叶华 陈平 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期407-411,共5页
To extract the cable forces due to dead load in cable-stayed bridges from the monitoring data,the effects of various factors are eliminated step by step by different statistical methods.The information of cable tensio... To extract the cable forces due to dead load in cable-stayed bridges from the monitoring data,the effects of various factors are eliminated step by step by different statistical methods.The information of cable tension sensors recorded by the health monitoring system of Nanjing No.3 Yangtze River Bridge is taken as an example. Temperature effects are eliminated by linear fitting analysis;a 5-level wavelet de-noising method is applied to eliminate the noise signal by the wavelet basis function of DB8.The rest cable force data is tested by the method of extreme-value type-Ⅲ distribution, and the fitted location parameter is selected as the cable force due to dead load.The results show that the cable force has a linear relationship with temperature. Sometimes, the temperature effect is significant.Noise effect accounts for a small percentage,and the vehicle loads effect has twice the temperature effect on the traffic volume in 2007. The calculation results of other stay cables verify the reliability and validity of the proposed method. 展开更多
关键词 cable force health monitoring temperature effect distribution fitting
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一种新的半模糊化聚类方法
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作者 闫德勤 迟忠先 《计算机应用与软件》 CSCD 北大核心 2003年第8期72-73,共2页
本文对模糊聚类方法进行了分析 ,讨论了截集参数与FCM方法中参数m的关系及参数选取的依据。提出了一种上下截集半模糊聚类方法 (UD -SFCM) 。
关键词 半模糊化聚类方法 隶属矩阵元 数据集合 模糊集
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Detection and Analysis of Squalene in Oil from Olive Fruits of Different Varieties and of Different Degrees of Maturity 被引量:2
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作者 耿树香 宁德鲁 +2 位作者 张艳丽 陈海云 李勇杰 《Agricultural Science & Technology》 CAS 2013年第10期1482-1485,共4页
[Objective] This study aimed to identify the difference in squalene content among different olive varieties and the law of squalene content change in the same olive variety of different degrees of maturity, with the o... [Objective] This study aimed to identify the difference in squalene content among different olive varieties and the law of squalene content change in the same olive variety of different degrees of maturity, with the objective to provide technical support for the harvest and processing of olive fruits. [Method] Taking 13 introduced olive varieties including three varieties of eight different grades of maturity, fat acid w3s first extracted by Soxhlet extraction and then squalene was quantitatively and qualitatively analyzed by gas chromatography-mass spectrometry (GC-MS) method. [Result] The results showed that squalene content was the highest in CG-32, and the lowest in Leccino among the 13 olive varieties. And squalene content increased with the degree of maturity in the three olive varieties including CG-32, Frantoio and Ascolana Tenera. [Conclusion] A more simple and rapid method for the determina- tion of squatene content was established. 展开更多
关键词 OLIVE Olive oil Determination of squalene content GC-MS method
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Synthetical condition assessment of long span suspension bridge based on closeness degree and FAHP 被引量:1
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作者 郭彤 李爱群 +1 位作者 赵大亮 王浩 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期261-265,共5页
Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a math... Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a mathematical model of a multi-objective assessment of a long span suspension bridge is set up. An example is given to show the procedure in the synthetical condition assessment of the Runyang Suspension Bridge, which includes the hierarchical division, the definition of factor weights and fuzzy membership functions, and the calculation of closeness degrees, etc. The assessment combines both the data from the health monitoring system and the manual tests. The classification of evaluation items as well as the calculation of deterministic and nondeterministic items is presented. Compared with the traditional method of point rating, this method can better describe the discreteness of monitoring data and the fuzziness in the condition assessment. 展开更多
关键词 pattern recognition fuzzy analytic hierarchy process closeness degree synthetical condition assessment suspension bridge
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Ontology-based similarity measure for text clustering 被引量:1
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作者 颜端武 李晓鹏 +1 位作者 王磊 成晓 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期389-393,共5页
A method that combines category-based and keyword-based concepts for a better information retrieval system is introduced. To improve document clustering, a document similarity measure based on cosine vector and keywor... A method that combines category-based and keyword-based concepts for a better information retrieval system is introduced. To improve document clustering, a document similarity measure based on cosine vector and keywords frequency in documents is proposed, but also with an input ontology. The ontology is domain specific and includes a list of keywords organized by degree of importance to the categories of the ontology, and by means of semantic knowledge, the ontology can improve the effects of document similarity measure and feedback of information retrieval systems. Two approaches to evaluating the performance of this similarity measure and the comparison with standard cosine vector similarity measure are also described. 展开更多
关键词 similarity measure text clustering ONTOLOGY information retrieval system
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打退与嚇退
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作者 宋民政 《今日中国》 1989年第1期71-72,共2页
古之用兵者,皆知「打退不如嚇退」之妙。赵云以寡遇众,便偃旗息鼓,大开营门,使曹操疑有伏兵,引军而走。张飞独自断后,横戈立马,一声大喝,曹军将士心胆欲裂,落荒而逃。然而,观之一些「嚇退」的战例,皆为行险履薄,不得已而为之。所谓「设... 古之用兵者,皆知「打退不如嚇退」之妙。赵云以寡遇众,便偃旗息鼓,大开营门,使曹操疑有伏兵,引军而走。张飞独自断后,横戈立马,一声大喝,曹军将士心胆欲裂,落荒而逃。然而,观之一些「嚇退」的战例,皆为行险履薄,不得已而为之。所谓「设疑以却敌」。倘若被对方探知为「诈」,则不但难收「嚇退」之故,恐怕还会为敌所擒。故而实力雄厚,胜券稳操者,大多不用「嚇退」,而用「打退」。 展开更多
关键词 设疑 大阴 今日中国 劳燕 心腹大患 度索 服重 海内外人士
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Multiple vehicle routing problem integrated reverse logistics with fuzzy reverse demands
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作者 李建 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期222-227,共6页
A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in t... A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in the demands of the clients. The deliveries of every client as uncertain parameters are expressed as triangular fuzzy numbers. In order to describe MVRPRL, a multi-objective fuzzy programming model with credibility measure theory is constructed. Then the simulationbased tabu search algorithm combining inter-route and intra-route neighborhoods and embedded restarts are designed to solve it. Computational results show that the tabu search algorithm developed is superior to sweep algorithms and that compared with handling each on separate routes, the transportation costs can be reduced by 43% through combining pickups with deliveries. 展开更多
关键词 reverse logistics pickup and delivery credibility measure theory tabu search algorithm fuzzy simulation
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Study on Dragline-Bulldozer Operation with Variations in Coal Seam Thickness 被引量:10
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作者 ZHOU Wei CAI Qing-xiang CHEN Shu-zhao 《Journal of China University of Mining and Technology》 EI 2007年第4期464-466,共3页
The dragline is one of the most promising surface mining machines in China. This paper studies the interac-tion between the working bench advancing speed and the stripping volume with variation in coal seam thickness.... The dragline is one of the most promising surface mining machines in China. This paper studies the interac-tion between the working bench advancing speed and the stripping volume with variation in coal seam thickness. Ad-justing the bulldozing volume (depth) and/or changing the dragline bench height are proposed as means to ensure a smooth and economical mining operation. When the coal seam is getting thicker it is recommended to reduce the bull-dozing volume (depth) for a higher dragline efficiency. When the coal seam is getting thinner it is recommended to in-crease the bulldozing volume (depth) to ensure the dragline can work at the proper bench height. 展开更多
关键词 open pit coal thickness variation DRAGLINE ADAPTABILITY BULLDOZER
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REASONS FOR THE LATE ONSET AND ANOMALOUS SOUTHWARD PERSISTENCE OF THE SOUTH CHINA SEA SUMMER MONSOON IN 2005 被引量:4
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作者 鲍媛媛 琚建华 +1 位作者 金荣花 康志明 《Journal of Tropical Meteorology》 SCIE 2010年第1期27-34,共8页
Features of atmospheric circulation and thermal structures are discussed using the NCAR/NCEP data to reveal the reasons for the late onset and anomalous southward persistence of the South China Sea Summer Monsoon(SCSS... Features of atmospheric circulation and thermal structures are discussed using the NCAR/NCEP data to reveal the reasons for the late onset and anomalous southward persistence of the South China Sea Summer Monsoon(SCSSM) in 2005.The results show that three factors are crucial.First,a strong Arabian High overlaps with a high-latitude blocking high and channels strong cold air to southern Asia.Second,the Tibetan Plateau has a bigger snow cover than usual in spring and the melting of snow cools down the surface.Third,the Somali Jet breaks out at a much later date,being not conducive to convection over Indochina.The former two factors restrict atmospheric sensible heating over the Tibetan Plateau and nearby regions while the third one limits latent heating over Indochina.All of the factors slow down atmospheric warming and postpone the onset of SCSSM.Long after the onset of SCSSM,strong cold air over India advances the Southwest Monsoon northward slowly,resulting in weaker convection and latent heating over the Tibetan Plateau and nearby areas.The negative feedback conversely inhibits further northward movement of Southwest Monsoon. 展开更多
关键词 South China Sea summer monsoon Arabian High Somali Jet snow cover
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Retrieval and Analysis of Coal Fire Temperature in Wuda Coalfield, Inner Mongolia, China 被引量:7
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作者 JIANG Weiguo ZHU Xiaohua +3 位作者 WU Jianjun GU Lei MA Guobin LIU Xiaochen 《Chinese Geographical Science》 SCIE CSCD 2011年第2期159-166,共8页
Coal fire burning around the world is an environmental catastrophe characterized by the emission of noxious gases, particulate matter, and condensation by-products. In this study, coal fire temperature is retrieved ba... Coal fire burning around the world is an environmental catastrophe characterized by the emission of noxious gases, particulate matter, and condensation by-products. In this study, coal fire temperature is retrieved based on Landsat 5 TM images and Generalized Single-Channel Algorithm (GSCA), in Wuda coalfield, Inner Mongolia, China. Then coal fire zones are extracted by Jenks′ natural breaks and threshold methods based on temperature images. Changes of coal fire zones are analyzed from 1989 to 2008. The results are summarized as follows: 1) The coal fire temperature retrieval method based on Landsat 5 TM and the GSCA model is effective and feasible, because the temperature error is relatively small (from –2.9℃ to +2.6℃) between the measured temperature and the retrieved temperature. 2) The accuracy is relatively high to extract coal fire zones through the Jenks′ natural breaks and threshold methods, because 83.56% of surveyed area is located in the coal fire zones extracted in 2005. 3) The coal fire area increased 9.81 × 10 5 m 2 from 1989 to 2005, and the annual growth is about 6.1 × 10 4 m 2 , with an annual increasing rate of 2.48%. The area of coal fire decreased by 8.1 × 10 5 m 2 from 2005 to 2008. 展开更多
关键词 coal fire temperature retrieving Generalized Single-Channel Algorithm Landsat 5 TM Wuda coalfield Inner Mongolia
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A Sensitive High-Performance Liquid Chromatography Coupled with Solid- Phase Extraction for Determination of Fexofenadine in Beagle Plasma 被引量:2
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作者 马雷 殷莉莉 +1 位作者 孙进 何仲贵 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期246-249,共4页
Introduction Fexofenadine, the primary metabolite of terfenadine, is a selective and peripherally acting Hl receptor antagonist and has been developed as a non-sedating H1 antihistaminic drug. In clinical studies, it ... Introduction Fexofenadine, the primary metabolite of terfenadine, is a selective and peripherally acting Hl receptor antagonist and has been developed as a non-sedating H1 antihistaminic drug. In clinical studies, it is used for the treatment of seasonal allergic rhinitis and chronic urticaria without producing sedation. 展开更多
关键词 RP-HPLC FEXOFENADINE beagles PLASMA solid-phase extraction
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Influence of central buckle on suspension bridge dynamic characteristics and driving comfort 被引量:3
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作者 王达 邓扬 刘扬 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3108-3115,共8页
The central buckle, which is often used in a suspension bridge, can improve bridges' performance in the actual operation condition. The influence of the central buckle on natural vibration characteristics and brid... The central buckle, which is often used in a suspension bridge, can improve bridges' performance in the actual operation condition. The influence of the central buckle on natural vibration characteristics and bridge-deck driving comfort of a long-span suspension bridge is studied by using a case study of Siduhe Suspension Bridge in China. Based on the finite element software ANSYS and independently complied program, the influence of the central buckle on the structure force-applied characteristics of a long-span suspension bridge has been explored. The results show that the huge increases of natural frequencies can result in the presence of central buckles because of the increases of bending and torsional rigidities. The central buckle basically makes the stiffening girders and cables within the triangular area covered as a relatively approximate rigid area. Hence, the central buckle can reduce the torsional displacement of the main girder. However, the increases of bending and torsional rigidities have little influence on the impact factor, which is obtained by using vehicle-bridge coupled vibration analysis. This means that the central buckle has little effect on the comfort indices. In addition, it is found that the central buckle can enhance the bridge deck's driving stability due to the decrease of the torsional displacements of the main girder. 展开更多
关键词 suspension bridge central buckle dynamic characteristic separation method impact factor
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Influence of rigid central buckle on seismic response of long-span suspension bridges 被引量:2
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作者 王浩 Li Aiqun Jiao Changke Zou Keguan 《High Technology Letters》 EI CAS 2011年第2期214-219,共6页
A rigid central buckle is employed in Runyang Suspension Bridge (RSB) to replace commonly used short suspenders in the main span. Based on the seismic waves with 2% probabilities of exceedance, the nonlinear seismic... A rigid central buckle is employed in Runyang Suspension Bridge (RSB) to replace commonly used short suspenders in the main span. Based on the seismic waves with 2% probabilities of exceedance, the nonlinear seismic response time-domain analysis are then conducted and influence of central buckles on seismic response of long-span suspension bridge is specially studied. Analysis resuits show that the central buckle can effectively control the longitudinal floating vibration mode of the deck, and therefore reduce earthquake-excited longitudinal displacement at the end of the deck. However, the central buckle may cause increment of longitudinal displacement at the top of main tower and bending moment at the bottom of the main tower, which should be paid special attention to. Results provide references for anti-earthquake analysis and design of long-span suspension bridges using rigid central buckles. 展开更多
关键词 suspension bridge central buckle seismic response time-history analysis ANSYS
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