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LINEAR ACTIVE STRUCTURES AND MODES (Ⅰ) —BASIC CONCEPTS AND PROPERTIES

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Applied Mathematics and mechanics(English Edition) 2004年第8期25卷 845-853页

作者：张景绘龚靖school of civil engineering and mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China Department of civil engineering Northeast China Institute of Electric Power Jilin 132012 P.R.China 王永刚school of civil engineering and mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China school of Science Chang'an University Xi'an 710064 P.R.China school of civil engineering and mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China

Some basic concepts about the active structures were firstly explained, and the main subjects to study in the field of active structure dynamics were synthesized. For the linear active structures, the annotations on the modes were done in detail. The physical meanings of the right and left eigenvectors were explained. The right eigenvectors are the modal shapes and the modal responses of an active structure depend on the left ones. The adjoint structure of an active structure was defined and the reciprocity theorem was interpreted. For two active structures, which are adjoint to each other and with the reciprocal gain-matrices, the right and left eigenvector are reciprocal. The relationship between an active structure and the corresponding passive structure is expressed with the transfer functions, which is employed to resolve the estimation problems.

关键词： active structure vibration control smart structure mode

STABLE OR UNSTABLE CRACK GROWTHSIN THIN ROCK PLATE UNDER COMPRESSION FOR PREDICTING BUCKLING ROCKBURST

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岩石力学与工程学报 2003年第12期22卷 2011-2018页

作者： Liu Xiaoming (school of civil and Architecture engineering,Wuhan University, Wuhan 430072 China) school of civil and Architecture engineering Wuhan University Wuhan 430072

Underground cavern opening can cause the surrounding rock tangential compressive stress to raise rapidly. Such high compressive stress increase can result in some original pre-existing cracks growing parallelly to the free surface of the remaining rock. This paper presents a model of crack stable or unstable propagation under compressive stress in thin layers that are separated from the main rock mass due to crack growth. Based on this analysis of flat plate buckling,a rock burst mechanism is presented. Immediate and delayed rock burst mechanism are proposed to explain time dependency in brittle rock sub-critical crack growth under compression. Influence of free surface on the surface-parallel crack growth is also discussed.

关键词：岩爆屈曲失稳机制粗糙度矿物

基于有效惯性矩的钢纤维高强混凝土梁刚度计算方法

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中国公路学报 2013年第5期26卷 62-68,139页

作者：高丹盈张明郑州大学土木工程学院河南郑州450002 安阳师范学院建筑工程学院河南安阳455000

在13根钢纤维高强混凝土梁等幅疲劳试验基础上，探讨了等效应力比、铜纤维类型、钢纤维体积率、铜纤维掺入范围和混凝土强度对钢纤维高强混凝土梁挠度和刚度的影响，建立了基于有效惯性矩的钢纤维高强混凝土梁刚度计算模型及公式。结果... 详细信息

在13根钢纤维高强混凝土梁等幅疲劳试验基础上，探讨了等效应力比、铜纤维类型、钢纤维体积率、铜纤维掺入范围和混凝土强度对钢纤维高强混凝土梁挠度和刚度的影响，建立了基于有效惯性矩的钢纤维高强混凝土梁刚度计算模型及公式。结果表明：在高强混凝土梁中掺入钢纤维提高了梁的截面刚度，使疲劳荷载作用下高强混凝土梁跨中挠度减小15％～61％；基于有效惯性矩的钢纤维高强混凝土梁挠度和刚度计算结果与试验结果吻合较好。

关键词：桥梁工程高强混凝土梁疲劳试验钢纤维挠度刚度

NUMERICAL MODELLING OF ROCK FALL USING EXTENDED DDA

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岩石力学与工程学报 2003年第6期22卷 926-931页

作者： Chen Guangqi (Graduate school of civil and Structural engineering, Kyushu University, Fukuoka 816-8581 Japan) Graduate school of civil and Structural engineering Kyushu University 日本 Fukuoka

The reasonable design of protective structures to mitigate the hazards from rock fall depends on the knowledge of motion behaviors of falling stones,such as the falling paths,velocities,jump heights and *** simulation is an effective way to gain such kind of knowledge,In this paper,the discontinuous deformation analysis (DDA) is applied to rock fall *** order to obtain more reliable results,the following improvements and extensions are made on the original DDA.(1)Solve the problem of block expansions due to rigid body rotation error.(2) Add the function of modeling the drag resistance from air and plants so that the velocities of falling stones obtained by simulations are good enough in agreement with those by experiments in situ.(3)Add the capability to consider energy loss due to block collisions so that the jumping heights and distances obtained by simulations are good enough in agreement with thos by experiments even for the slope with very soft layer on its *** of application examples is presented to show that the extended DDA is very effective and useful in rock fall ***,the presented method is expected to be put into wide use in slop stability analysis.

关键词：岩石力学 DDA 落石运动岩石力学能量损耗 DDA 边坡

Stress-dependent undrained shear behavior of remolded deep clay in East China

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2015年第3期16卷 171-181页

作者： Xiang-yu SHANG Guo-qing ZHOU Yong LU State Key Laboratory for Geomeehanics and Deep Underground engineering China University of Mining and Technology Xuzhou 221116 China school of mechanics & civil engineering China University of Mining and Technology Xuzhou 221116 China school of civil engineering Suzhou University of Science and Technology Suzhou 215009 China

Consolidated-isotropically undrained triaxial compression （CIUC） tests were performed on the reconstituted deep clay from a mine in East China. It was consolidated to maximum stresses in the range of 0.3-2.6 MPa. The test results show that the stress-strain-strength properties of the clay during undrained shear are significantly stress-dependent. In particular, in the case of high consolidation pressure, the post-peak drop in strength on stress-strain curves and shear plane in soil specimens are more evident, the peak stress ratio and the axial strain at which this ratio was reached are smaller, and the relationship between pore pressure and axial strain is also significantly different from that for the case of low consolidation pressure. The environmental scanning electron microscope observations and micro analysis lead to an understanding of the physical mechanisms underlying the above stress-dependent mechanical behavior. In addition, the CIUC behaviors of the studied clay are discussed in the context of critical state soil mechanics.

关键词： Deep clay High pressure Undrained triaxial compression Stress-dependent behavior

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复合材料层合厚板后屈曲

上海交通大学学报 1998年第11期32卷 78-83页

作者：沈惠申上海交通大学建筑工程与力学学院

基于Ｒｅｄｄｙ高阶剪切变形板理论，给出复合材料层合厚板在单向压缩作用下的后屈曲分析．分析中应用了由该理论导出的广义大挠度Ｋａｒｍａｎ型方程，考虑两种面内边界条件并计及板的初始几何缺陷．采用摄动法确定板的屈曲载荷和后屈... 详细信息

基于Ｒｅｄｄｙ高阶剪切变形板理论，给出复合材料层合厚板在单向压缩作用下的后屈曲分析．分析中应用了由该理论导出的广义大挠度Ｋａｒｍａｎ型方程，考虑两种面内边界条件并计及板的初始几何缺陷．采用摄动法确定板的屈曲载荷和后屈曲平衡路径，给出四边简支反对称角铺设和对称正交铺设层合板的数值结果，同时讨论了横向剪切变形、长宽比、铺层数、面内边界条件和初始几何缺陷等各种参数变化的影响．

关键词：屈曲后屈曲厚板剪切板理论复合材料层合板

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基于逆有限元的应变模态损伤检测方法

振动．测试与诊断 2017年第1期37卷 147-152页

作者：杨海峰吴子燕孙蓬张坤西北工业大学力学与土木建筑学院西安710129 西北工业大学计算机学院西安710129

基于光纤光栅传感器(fiber Bragg grating,简称FBG)逆有限元方法(inverse finite element method,简称iFEM),仅利用有限测点的应变数据进行全域应变场重构,得到近似完全测量应变模态,提高了直接采用实测应变数据来构建应变模态损伤指标... 详细信息

基于光纤光栅传感器(fiber Bragg grating,简称FBG)逆有限元方法(inverse finite element method,简称iFEM),仅利用有限测点的应变数据进行全域应变场重构,得到近似完全测量应变模态,提高了直接采用实测应变数据来构建应变模态损伤指标的实用性。利用基于损伤应变模态差分原理的损伤指标法,只需用损伤后应变模态数据即能定位损伤,并给出了损伤指标数学模型。计算结果表明,基于光纤光栅传感器和逆有限元方法可以快速进行全域应变场重构,为基于应变模态的损伤检测提供数据保障,而应变模态差分曲线只在损伤处发生剧烈变化,损伤程度不同,曲线突变程度略有不同但规律一致。最后以某板的实验结果证明了该方法的有效性。

关键词：逆有限元法损伤检测应变模态光纤光栅传感器

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火箭弹发射过程冲击流场压力和温度实验测量

推进技术 2003年第6期24卷 514-516,520页

作者：徐强南京理工大学机械工程学院江苏南京210094

考虑燃气流场的冲击效应,根据冲击特点对燃气作用区域的装置结构和强度进行合理的设计,以获得有效的导流和防护效果。实验对火箭发射阶段管后冲击流场在平面斜钢板上的流动参数进行了测量。得到了火箭燃气射流对倾斜钢板热冲击的最大滞... 详细信息

考虑燃气流场的冲击效应,根据冲击特点对燃气作用区域的装置结构和强度进行合理的设计,以获得有效的导流和防护效果。实验对火箭发射阶段管后冲击流场在平面斜钢板上的流动参数进行了测量。得到了火箭燃气射流对倾斜钢板热冲击的最大滞止压力和温度,以及冲击流场的压力与温度分布,并确定了管后燃气冲击流场的危险区域。

关键词：火箭发动机燃气流冲击影响压力测量温度测量

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频率测量模式在薄板分层损伤探测中的应用

振动．测试与诊断 2015年第3期35卷 535-540,595页

作者：成鑫磊肖光宏 Kennedy D 成培江重庆交通大学土木建筑学院重庆400074 卡迪夫大学工程学院后勤工程学院土木工程系重庆401311

分层损伤是复合材料的主要破坏形式之一,该类损伤发展到一定程度时,不仅会导致结构承载力降低,更有可能因结构失效而引起灾难性破坏。针对此问题,基于固有频率易于测量、测量精度高的特点,将正交化后的固有频率变化量应用于含有分层损... 详细信息

分层损伤是复合材料的主要破坏形式之一,该类损伤发展到一定程度时,不仅会导致结构承载力降低,更有可能因结构失效而引起灾难性破坏。针对此问题,基于固有频率易于测量、测量精度高的特点,将正交化后的固有频率变化量应用于含有分层损伤的复合材料薄板结构中,提出了一种新型反向确定结构损伤位置的理论方法。该方法应用于无损检测中,作为结构损伤定量检测的前期工作,在定量无损检测之前,可以一定范围内准确地预测分层损伤的位置,提高检测效率。利用该方法对复合材料薄板分层损伤位置进行了探测,并与试验结果进行了对比分析。结果表明,该方法具有较好的精确性,实施步骤简单、可靠,并具有一定的抗噪性。

关键词：固有频率薄板结构分层损伤位置预测