Dynamic Inelastic Numerical Simulation for a Shaking Table Test of a Full Scale Steel Moment Frame Structure based on OpenSEES
Chen Xuewei Han Xiaolei Jack CHEANG Lin Shengyi Mao Guiniu

ABSTRACT :
This paper presents a Dynamic nonlinear numerical simulation of a 4-story full-scale steel moment frame structure based on OpenSEES. Fiber model which has fewer DOFs is used for structure member simulation.
The responses of the structure under frequent, moderate and severe ground motions are predicted prior to the full-scale shake-table test. Correlated with the experimental results, the analytical results confirm the accuracy of the numerical simulation method, in both representing the inelastic behavior and the failure mechanism. The seismic responses and the collapse moment under severe ground motion are precise predicted. The study establishes the validity of the inelastic analysis method of overall structure based on fiber model, which is suitable for seismic analysis of overall structure.

KEYWORDS: Inelastic Time-History Analysis, Steel Frame, Full Scale Specimen, Shaking Table Test, Blind Analysis

Download:Dynamic Inelastic Numerical Simulation for a Shaking Table Test of a Full Scale Steel Moment Frame Structure based on OpenSEES

Numerical Analysis of Cyclic Loading Test of Shear Walls based on OpenSEES
Han Xiaolei Chen Xuewei Jack CHEANG Mao Guiniu Wu Peifeng

ABSTRACT :
Neither the original structure nor the altered structure of the Garden Hotel in Guangzhou accords with the ductile details of seismic design based on current Chinese codes. In order to explore the seismic performance of the original shear wall structure and the altered shear wall structure, the cyclic loading testes of the shear walls with different reinforcement ratio and constructional details are carried out. This paper presents the numerical analysis of the cyclic loading testes of shear walls with SWNA (Shear Wall Nonlinear Analysis) program. SWNA program is secondary developed based on OpenSEES and MVLEM. Compare with the testes, the numerical results confirmed the accuracy of this analysis procedure in representing the nonlinear behavior of the shear wall, such as the shifting of natural axis, shear deformation, local collapse and collapse mechanism. The analysis procedure based on MVLEM, which saves the calculating cost due to fewer DOFs, can stimulate the nonlinear behavior of the shear wall, and fit for global inelastic analysis and performance based design of tall building structure.

KEYWORDS: Shear wall, Cyclic loading test, OpenSEES, MVLEM, Nonlinear analysis

Download:Numerical Analysis of Cyclic Loading Test of Shear Walls based on OpenSEES.pdf

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2008年10月13日至17日，在北京市九华山庄召开了第十四届世界地震工程大会。大会分keynote, oral presentation, poster presentation and exhibition 四个环节。各个环节都很精彩，可是我分身乏术，我只能参加我感兴趣的几个section，如数值分析方法，混凝土结构及倒塌分析等。在会中见到很多国际知名的结构分析专家，如我的偶像而未曾见过面的，曾经帮过我很大忙的Matej Fischinger教授，kasai教授，Hikino博士等等。而且与久仰的结构大师Kabeyasawa见面及合照。
通过这个会议认识了很多大牛，还有认识了一个志同道合的Berkeley的学生，在coffee shop聊opensees的开发聊了很久，这个会议是国际地震工程学术的交流平台。在presentation里面，学到很多国际先进的试验及分析技术。我在POSTER里面宣讲我的两篇关于OPENSEES的论文，呵呵，在宣讲时也认识了一些朋友。这个会议太难忘了，于是如无意外，我会继续参加15wcee的。
The 14th conference of earthquake engineering is hold in Qiuhua hotel in Beijing on 13th October 2008. The conference for engineers work on earthquake is just like the Olympic game for athlete. The engineers and researchers form many countries has come here to discuss, to communicate, to learn and to see. The conference is made up by four parts: Keynote, oral Presentation, Poster Presentation and Exhibition. Every part of it is very wonderful. oral presentation and Poster Presentation are parallel, but I cannot divide myself into two parts, so I could only join several sections which I am very interested in. For example, simulation methods, concrete structure and collapse analysis. In the conference, I meet a lot of famous researchers such as Prof. Matej Fischinger who had help me a lot in my research but we just contact by Email. After the conference I had meet some new friend, some PhD students, such as Mr. Andreas. We meet in the coffee shop of the hotel. We talked about the technical problem about “OpenFresco” in the evening. The conference is the best communicate platform for academe of earthquake engineering. In the Presentation I have learned a lot of advanced technology of analysis and experiment. I also have an opportunity to show my two research papers. The conference is so great, and thenI think I will join the next world conference of earthquake engineering (15WCEE).

Research On The Seismic Design Of Transfer-Storey Structures Based On Philosophy Of Capacity Design Under Severe Earthquake
Jack CHEANG Han Xiaolei  Tang JianQiu   Chen Xuewei

ABSTRACT :
Both theoretical analysis and engineering applications of the transfer-storey structures are mostly limited in elastic stage under frequent earthquakes; the structural behavior after yielding under severe earthquake need to be studied by elastic-plastic analysis. And there is no specific and quantitative method to ensure that transfer structures can “resist severe earthquake without collapse”.  In this paper, the philosophy of capacity design is introduced into the design of transfer-storey structures and a practical design method for transfer structures under severe earthquake is presented. Through push-over analysis, various limit states of coupled shear walls are disclosed. Parameters that influence significantly the structure behavior such as integer coefficient of coupled shear walls, reinforcement ratio of coupling beams and height-width ratio of shear walls are highlighted. The shear overstrength of the coupling beams under the ideal limit state is reduced with reduction coefficient K. Overstrength of shear walls is derived by ultimate state analysis, which considers the axial forces increment of shear walls caused by shear overstrength of coupling beams. On this basis, mechanical characteristics and capacity based seismic design method of transfer storey under severe earthquake are studied by elastic-plastic analysis. A series of nonlinear dynamic time-history analysis has been completed, which considers the influence of varied parameters including the stiffness and mass of transfer structures, seismic protected intensity and the position of transfer storey. Moreover, the simplified formulas and the detail procedure for capacity design of transfer structures are presented.

KEYWORDS: philosophy of capacity design, design of transfer-storey, structural overstrength, push-over analysis, nonlinear dynamic time-history analysis, severe earthquake

Download:RESEARCH ON THE SEISMIC DESIGN OF TRANSFER-STOREY STRUCTURES BASED ON PHILOSOPHY OF CAPACITY DESIGN UNDER SEVERE EARTHQUAKE

Current version is: 2.0.0

Your last download was on Thu Jan 10 07:29:54 2008,
and the version was 1.7.5.

OpenSees executables for Windows 98/2000/NT/XP/Vista are available for download. The current version of OpenSees has been tested and is generally stable. However, users may encounter problems when running a new problem for the first time. For that reason we we strongly encourage you to participate in the various message boards hosted by OpenSees. And please report any bugs you find! That, of course, is the whole reason we make these binaries available.
OpenSees uses Tcl/Tk, a general purpose scripting language that we have extended with commands for OpenSees. It is necessary to download a DLL for the Tcl/Tk interpreter.
The first step is download the two files below. The first file a zip file containing the OpenSees executable. The second file is a self-installing executable for Tcl/Tk.
Note that for those of you who have downloaded before, YOU WILL HAVE TO INSTALL Tcl/Tk LIBRARIES AND HEADER FILES AGAIN. This is because we have upgraded to Tcl/Tk Version 8.4.6

After downloading the Tcl/Tk executable you will need to run it to install the DLL's on your computer. As can be seen in the downloading section of the Getting Started Manual you will be asked were to install the files. Currently the default is C:\tcl. It is essential that you change this to "C:\Program Files\Tcl" during the course of the installation. If when you start OpenSees, you see an error message to the effect, "Cannot find tcl84.dll", you have skipped this step and must reinstall tcl. Note that you wil probably have to uninstall the version you just installed first.

Finally, locate the opensees.exe in a convenient directory. It is advisable to execute OpenSees from a DOS shell and you are ready to go!

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我校学生在国际结构振动台分析竞赛中获得第三名
2008年10月09日 10:32:23 浏览次数：1840

获奖证书

    近日，土木与交通学院博士研究生陈学伟、硕士研究生彭樵斌在韩小雷教授的指导下，参加国际结构振动台分析比赛并在比赛中获得3D科研组第三名的好成绩。
    该比赛由Blind Analysis Contest第14届世界地震工程会议和日本防灾科学技术研究所兵库抗震工学研究中心联合举办。比赛分四个组：3D科研组、3D工程组、2D科研组及2D工程组，要求对一全尺寸钢框架结构进行地震台试验前期分析，提交分析结果(包括地震响应及倒塌时间)并与震动台试验结果进行对比，以结果的准确性作为评选的标准。
    来自中国、日本、美国、新西兰、意大利、英国等国家和地区的47支队伍参加了本次比赛，其中包括多所在工程抗震领域有前沿性科研贡献的日本及美国的著名大学和研究所，代表了工程抗震的结构非线性领域的最高水平。
    本次比赛结果将于2008年10月在北京举办的第14届世界地震工程会议上宣布并展示抗震分析最新成果。 获奖名单及比赛情况可访问本次活动的网站：http://www.blind-analysis.jp/。（图文/通讯员 陈昕 土木与交通学院  编辑/龚华萍）
Today, my name is appear on the website of the university news. The news is about the award I get recently. The award I mentioned is the third place of the blind analysis contest. Let me introduce the contest. Blind analysis contest is hold in Japan in 2007, organize by 14th world conference of earthquake engineering and NIED which is a research institute in Japan. The content of the contest is asking the researcher to do analysis of a real steel frame structure before the shaking table test. Before the test, researcher should hand in the report of the response of the structure under an simulated earthquake named “Takatori”. The team whose result is close to the test result will win the award. Many researchers form many countries (China, Japan, United States, New Zealand, Italy, United Kingdom), 47 teams are join into the contest. All these teams represent the new technology and advance method in structure seismic analysis. After a few months, the contest result come out, and we got the third place and it’s broadcasted on the internet. I felt so happy and couldn’t sleep at night.
转载网址：http://202.38.194.228:8880/newsDetail.jsp?id=52884

DinoPTESAP v1.0 常应力(应变)单元有限元程序的开发

DinoPTESAP v1.0 这是我本科时候的作品，与Dino Sap v1.0 一样通过编程的方法去了解及体会静力学有限元方法的基本原理，通过一些美术功底与前后处理技术，并参考美国的SAP4源程序（我认为学生有限元的学生一定要看的源代码）开发的第二个有限元程序，当然第一个是DINOSAP，这两个程序是练手之作来的。常应变(应力)三角形单元CST的原理在有限元法一书（王勖成）或弹性力学（徐芝纶）一书都有介绍，原理与编制过程我就不详细阐述，学习有限元的学生通过编写这个程序会基本了解弹性静力学有限元的基本过程。在sap2000，ANSYS等程序中，都已经没有CST单元了，基本上最小阶次的单元都是二次元，教师在用ANSYS教学有限元时，往往不能SHOW一下常应变(应力)三角形单元的不足之处。这个程序就可以能过图形直观了体现常应变(应力)单元的性态了。

结构有限元模型采用3DSMAX建模后导入，3DSMAX有部分插件是可以实现网格划分的。导入后，在DINO PTESAP中建立约束，荷载，厚度弹性模量等信息后进行静力分析，最后结果可以显示变形及应力（应变）云图。

点击下载Dino PteSap v1.0

程序界面图（结构变形图）

结构应力 stress-y 图

以前在www.okok.org 上发表过的，求解一些不规则空间曲面有用到的程序，Dino Area Calculator 程序，原理与有限元的基本原理一样，求面积的过程是积分，积分的求解可以是通过公式来求出解析解计算得到，但对于复杂曲面，描述的公式可以很复杂，因此可以选择离散法，先将曲面离散成很多三角或四边面，然后以求和代替求积分。

软件操作说明：
1.用3DSMAX对计算的模型进行建模,细分网格;
2.输出ASCII文件,后辍为*.ASE,精度为七位;
3.打开面积求解器,计算表面积与重心;

点击下载：

在3dsmax建立半椭球表面并细分网格

在Dino Area Calculator 计算表面积

珠海天朗海峰国际中心_基于性能抗震分析

珠海天朗海峰相关网站：http://www.zhtlhf.com/

2008年8月完成了珠海天朗海峰国际中心的超限初步设计，采用了PERFORM-3D对其进行了弹塑性时程分析及基于性能的抗震评估。由于PERFORM-3D的建模非常复杂，所以我开发了一个ETABS TO PERFORM-3D的前处理，可以实现在ETABS建立几何模型，再通过我开发的前处理系统输入配筋与纤维截面划分，再导入PERFORM-3D完成非线性模型。PERFORM-3D 上述基于纤维模型（PERFORM-3D）的弹塑性分析的研究已初步完成论文《基于纤维模型的超高层钢筋混凝土结构弹塑性时程分析及工程应用》，正准备发表！PERFORM-3D是一个很不错的软件，可以输出大量工程关心的结果，塑性铰转角及能量耗散情况。

PERFORM-3D三维模型

PERFORM-3D前处理系统 ETP(ETABS TO PERFORM-3D)程序

DinoSap v1.0 算例2

算例2：《结构力学教程(I)》例题8-4,试求图所示吊桥结构的内力图，吊桥的EA等于横梁EI的1/20m-2

图 吊桥结构图

①打开DinoSap V1.0程序,点击按钮 打开显示控制对话框,在Userinterface选择Paper_Style;Grid_Size选5.0,Pressure_Dens填2.0,Force-Length 填50;如图所示选择;

图 显示设置

②这时每个单元格代表5m×5m,点击 增加结点,按结构形状增加6个结点;
③点击增加材料按扭如图,增加两种材料一种是梁,一种是拉杆,梁E=1,I=20,A=-1,拉杆E=1,I=-1,A=1;(-1代表无穷大);

图 修改材料属性

④点击增加单元按钮,修改两端约束与材料,点击始点与终点,建立模型;
⑤点击增加支座按钮增加拉杆的支座,再点击 增加梁端固接支座;
⑥点击增加线性荷载 ,增加桥面的10kN/m均布荷载
最终结构计算简图如图所示;
点击绘制内力图的三个按钮 得到全部内力图

 
弯矩图(kNm)

剪力图(kN)

轴力图(kN)

结果与课本手算是一致的。可见软件计算精确性。DINOSAP V1.0具有一个非常实用的功能是在同一个界面可以建出几个独立的结构模型，计算内力做比较。如图所示。