检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

采用Kalman滤波器的实时混合试验方法

结构工程师 2011年第B1期27卷 52-56页

作者：史鹏飞吴斌 billie f. spencer, jr. Brian M. Phillips Chia-Ming Chang 哈尔滨工业大学土木工程学院黑龙江哈尔滨150090 美国伊利诺伊大学香槟建筑与环境工程学院伊利诺伊61801

等效力控制方法采用力反馈控制代替隐式积分方法中的迭代过程,从而使等效力控制方法在避免隐式积分方法的迭代过程的同时仍具有隐式积分方法的无条件稳定性。利用该力反馈控制,等效力控制方法还具有对实时子结构试验中的时滞进行补偿的... 详细信息

等效力控制方法采用力反馈控制代替隐式积分方法中的迭代过程,从而使等效力控制方法在避免隐式积分方法的迭代过程的同时仍具有隐式积分方法的无条件稳定性。利用该力反馈控制,等效力控制方法还具有对实时子结构试验中的时滞进行补偿的作用。但是,在实际的实时子结构试验中,能够影响等效力控制方法时滞补偿效果的因素有很多,噪声就是其中之一。本文研究了噪声对等效力控制方法稳定性的影响。提高等效力PID控制器的比例增益可对系统时滞起到补偿作用,但是当比例增益较大时,等效力反馈中的噪声会降低等效力控制方法的稳定性。为了对等效力反馈中的噪声进行滤波,本文采用了基于作动器模型设计的Kalman滤波器,并通过实时子结构实验方法对其滤波效果进行研究。研究结果表明此滤波器能够有效地过滤噪声,消除噪声对等效力控制方法稳定性的影响。

关键词：实时子结构实验等效力控制 Kalman滤波器磁流变阻尼器

Model-based f.amework f.r multi-axial real-time hybrid simulation testing

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2017年第4期16卷 671-691页

作者： Gaston A.f.rmandois billie f.spencer,jr. Department of.Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

Real-time hybrid simulation is an ef.icient and cost-ef.ective dynamic testing technique f.r perf.rmance evaluation of.structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit signif.cant dynamic coupling of.the actuators and suf.er f.om time lags that are associated with the dynamics of.the servo-hydraulic system, as well as control-structure interaction （CSI）. One approach to reducing experimental errors considers a multi-input, multi-output （MIMO） controller design, yielding accurate ref.rence tracking and noise rejection. In this paper, a f.amework f.r multi-axial real-time hybrid simulation （maRTHS） testing is presented. The methodology employs a real-time f.edback-f.edf.rward controller f.r multiple actuators commanded in Cartesian coordinates. Kinematic transf.rmations between actuator space and Cartesian space are derived f.r all six-degrees-of. f.eedom of.the moving platf.rm. Then, a f.equency domain identif.cation technique is used to develop an accurate MIMO transf.r f.nction of.the system. f.rther, a Cartesian-domain model-based f.edf.rward-f.edback controller is implemented f.r time lag compensation and to increase the robustness of.the ref.rence tracking f.r given model uncertainty. The f.amework is implemented using the 1/5th-scale Load and Boundary Condition Box （LBCB） located at the University of.Illinois at Urbana- Champaign. To demonstrate the ef.icacy of.the proposed methodology, a single-story f.ame subjected to earthquake loading is tested. One of.the columns in the f.aane is represented physically in the laboratory as a cantilevered steel column. f.r real- time execution, the numerical substructure, kinematic transf.rmations, and controllers are implemented on a digital signal processor. Results show excellent perf.rmance of.the maRTHS f.amework when

关键词： real-time hybrid simulation multiple actuators dynamic coupling kinematic transf.rmations model-basedcompensation

在线全文

学校读者我要写书评

暂无评论

f.om the editors

Earthquake Engineering and Engineering Vibration 2024年第2期23卷 I0002-I0002页

作者： Qi Xiaozhai George C.Lee billie f.spencer IEM UB UIUC

Dear Members of.the Editorial Board, Contributors and f.iends of.the journal,This issue of.Earthquake Engineering and Engineering Vibration(Vol. 23, No. 2) includes f.ve papers in a special section entitled “Wave-Based Nondestructive Testing and Evaluation Methods in Civil Engineering”. The special section aims to present recent developments and applications of.wave-based nondestructive testing and evaluation research. We thank the guest editors, Prof. Nenad Gucunski of.Rutgers University, USA, Prof. Lin Shibin of.Jianghan University, China and Prof. Chen Hongbing, University of.Science and Technology Beijing, China, f.r their hard work and dedication.

关键词： Earthquake journal section

TopSTO:a 115-line code f.r topology optimization of.structures under stationary stochastic dynamic loading

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2023年第4期22卷 1081-1100页

作者： Sebastian Pozo f.rnando Gomez Thomas Golecki Juan Carrion billie f.spencer jr. Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbana 61801ILUSA College of.Science and Engineering Universidad San Francisco de QuitoDiego de Robles y Vía InteroceanicaQuitoEcuador Skidmore Owings&MerrillLLPChicago 60604ILUSA Department of.Civil Engineering University of CuencaCuencaEcuador

The use of.topology optimization in structural design under dynamic excitation is becoming more prevalent in the *** many such applications utilize f.equency or time domain f.rmulations,relatively f.w consider stochastic dynamic *** paper presents an ef.icient and compact code called TopSTO f.r structural topology optimization considering stationary stochastic dynamic loading using a method derived f.om random vibration *** theory,described in conjunction with the implementation in the provided code,is illustrated f.r a seismically excited *** work demonstrates the ef.iciency of.the approach in terms of.both the computational resources and minimal amount of.code *** code is intended to serve as a baseline f.r understanding the theory and implementation of.this topology optimization approach and as a f.undation f.r additional applications and developments.

关键词： topology optimization stochastic dynamics matlab python

Development of.a building inf.rmation model-guided post-earthquake building inspection f.amework using 3D synthetic environments

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2023年第2期22卷 279-307页

作者： Nathaniel M.Levine Yasutaka Narazaki billie f.spencer Department of.Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Zhejiang University-University of.Illinois at Urbana-Champaign Institute Zhejiang UniversityHaining 314400China

Computer vision-based inspection methods show promise f.r automating post-earthquake building *** methods survey a building with unmanned aerial vehicles and automatically detect damage in the collected ***,assessing the damage′s impact on structural saf.ty requires localizing damage to specif.c building components with known design and *** paper proposes a BIM-based automated inspection f.amework to provide context f.r visual surveys.A deep learning-based semantic segmentation algorithm is trained to automatically identif. damage in *** BIM automatically associates any identif.ed damage with specif.c building ***,components are classif.ed into damage states consistent with component f.agility models f.r integration with a structural *** demonstrate the f.amework,methods are developed to photorealistically simulate severe structural damage in a synthetic computer graphics environment.A graphics model of.a real building in Urbana,Illinois,is generated to test the f.amework;the model is integrated with a structural analysis to apply earthquake damage in a physically realistic manner.A simulated UAV survey is f.own of.the graphics model and the f.amework is *** method achieves high accuracy in assigning damage states to visible structural *** assignment enables integration with a perf.rmance-based earthquake assessment to classif. building saf.ty.

关键词： computer vision earthquake engineering building inf.rmation model physics-based graphics model synthetic environment

Damper placement f.r seismic control of.super-long-span suspension bridges based on the f.rst-order optimization method

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2010年第7期53卷 2008-2014页

作者： billie f.spencer Department of.Civil and Environmental Engineering University of Illinois at Urbana-Champaign

To ensure the anti-earthquake perf.rmances of.super-long-span suspension bridges, ef.ective devices should be employed to control the seismic response of.key sections. In this paper, f.ur kinds of.assessment f.nctions f.r seismic response control ef.ect are f.rmulated based on the mechanism of.seismic response control with dampers and the seismic response characteristics of.long-span suspension bridges. A new optimal placement method of.dampers using penalty f.nction and f.rst-order optimization theory is then proposed. Runyang suspension bridge (RSB) with a main span of.1490 m is then taken as an example. Af.er seismic response time-history analyses on RSB using dif.erent placements of.dampers, the analysis results are optimized by employing the optimal placement method and the optimal placements of.dampers with the f.ur assessment f.nctions are then achieved respectively. Comparison of.the f.ur optimal control ef.ects show that dif.erent assessment f.nctions can lead to dif.erent optimal placements when the number of.dampers is certain, but all placements of.dampers can reduce the seismic response of.RSB signif.cantly. The selection of.assessment f.nctions and damper optimal placement should be determined by the structural characteristics and by what is considered in the structures. Results also show that the f.rst-order optimization is an ef.ective method on determining the optimal placement of.dampers.

关键词： suspension bridge seismic control damper placement control ef.ect assessment f.rst-order optimization method

数据-物理耦合驱动的剪力墙结构响应模拟方法

在线全文

学校读者我要写书评

暂无评论

数据-物理耦合驱动的剪力墙结构响应模拟方法

A phased approach to enable hybrid simulation of.complex structures

第33届全国结构工程学术会议

作者：翟光浩严金辉 billie f.spencer 徐永嘉伊利诺伊大学厄巴纳香槟分校土木与环境工程学院浙江大学-伊利诺伊大学厄巴纳香槟分校联合学院

在土木工程领域中,准确高效的结构响应模拟对于规划、设计、建造和维护等各个环节至关重要。物理驱动和数据驱动方法在该领域都得到了广泛的应用。不过,传统的物理驱动的结构响应模拟方法存在难以逾越的"精度-效率"均衡瓶颈,而数据驱动... 详细信息

在土木工程领域中,准确高效的结构响应模拟对于规划、设计、建造和维护等各个环节至关重要。物理驱动和数据驱动方法在该领域都得到了广泛的应用。不过,传统的物理驱动的结构响应模拟方法存在难以逾越的"精度-效率"均衡瓶颈,而数据驱动方法在泛化性、可靠性和数据方面的高需求限制了其推广与工程应用。因此,亟需开发新颖的方法,实现高精度-高效率的结构响应模拟。为解决上述问题,本研究将创新性的提出"数据-物理耦合驱动的结构响应模拟方法"。具体而言,本研究首先讨论了耦合模拟的基本概念与框架。随后,构建了注意力增强的堆叠回归神经网络(ASRNN)架构并提出了相应的数据增广方法。最后基于典型框架-剪力墙结构案例开展了案例分析,验证了方法在精度-效率平衡方面的显著优势。

关键词：数据物理耦合驱动注意力增强的堆叠回归神经网络 OpenSeesPy 结构响应模拟框架-剪力墙结构

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 63-77页

作者： billie f.spencer jr. Chia-Ming Chang Thomas M.f.ankie Daniel A.Kuchma Pedro f.Silva Adel E.Abdelnaby Department of.Civil Engineering University of Illinois at Urbana-Champaign Nathan M.& Anne M.Newmark Endowed Chair Earthquake Engineering Research &Test Center Guangzhou University Associate Prof.ssor Wiss JanneyElstner AssociatesInc. Department of.Civil and Environmental Engineering University of Illinois at Urbana-Champaign Department of.Civil and Environmental Engineering George Washington University Department of.Civil Engineering University of Memphis Assistant Prof.ssor

Hybrid simulation has been shown to be a cost-ef.ective approach f.r assessing the seismic perf.rmance of.structures. In hybrid simulation,critical parts of.a structure are physically tested,while the remaining portions of.the system are concurrently simulated computationally,typically using a f.nite element model. This combination is realized through a numerical time-integration scheme,which allows f.r investigation of.f.ll system-level responses of.a structure in a cost-ef.ective manner. However,conducting hybrid simulation of.complex structures within large-scale testing f.cilities presents signif.cant challenges. f.r example,the chosen modeling scheme may create numerical inaccuracies or even result in unstable simulations; the displacement and f.rce capacity of.the experimental system can be exceeded; and a hybrid test may be terminated due to poor communication between modules(e.g.,loading controllers,data acquisition systems,simulation coordinator). These problems can cause the simulation to stop suddenly,and in some cases can even result in damage to the experimental specimens; the end result can be f.ilure of.the entire experiment. This study proposes a phased approach to hybrid simulation that can validate all of.the hybrid simulation components and ensure the integrity largescale hybrid simulation. In this approach,a series of.hybrid simulations employing numerical components and small-scale experimental components are examined to establish this preparedness f.r the large-scale experiment. This validation program is incorporated into an existing,mature hybrid simulation f.amework,which is currently utilized in the Multi-Axial f.ll-Scale Sub-Structuring Testing and Simulation(MUST-SIM) f.cility of.the George E. Brown Network f.r Earthquake Engineering Simulation(NEES) equipment site at the University of.Illinois at Urbana-Champaign. A hybrid simulation of.a f.ur-span curved bridge is presented as an example,in which three piers are experimentally controlle

关键词： hybrid simulation seismic perf.rmance evaluation phased approach curved bridge MUST-SIM f.cility

在线全文

学校读者我要写书评

暂无评论

基于SDLV方法的弹性薄板损伤识别

应用基础与工程科学学报 2016年第5期24卷 995-1005页

作者：逯静洲 billie f.spencer'jr 烟台大学土木工程学院山东烟台264005 伊利诺伊大学香槟分校土木与环境工程系美国伊利诺伊61801

Bernal通过对DLV(Damage Locating Vector)方法的改进,提出了SDLV(Stochastic Damage Locating Vector)方法,较好解决了环境激励下未知输入的DLV法应用问题.本文以两边简支的弹性矩形薄板为研究对象,采用弹性模量降低模拟损伤,基于SDLV... 详细信息

Bernal通过对DLV(Damage Locating Vector)方法的改进,提出了SDLV(Stochastic Damage Locating Vector)方法,较好解决了环境激励下未知输入的DLV法应用问题.本文以两边简支的弹性矩形薄板为研究对象,采用弹性模量降低模拟损伤,基于SDLV方法对弹性薄板在4种损伤工况下的损伤识别进行数值模拟研究,对比分析了各类损伤指标对识别精度的影响.工况1:靠近支座处的一个单元损伤;工况2:跨中处一个单元损伤;工况3:靠近支座处两个相邻单元损伤;工况4:跨中处2个相邻单元损伤.数值模拟结果验证了SDLV方法应用于弹性薄板损伤识别的可行性,损伤所在位置、损伤单元的数目以及损伤指标的选择对损伤识别精度有一定影响.基于SDLV方法弹性薄板的损伤识别指标可以有规则化主应力、内力和应变能3种选择,如果联合运用多种损伤指标,可以更准确地定位弹性薄板的损伤.

关键词：损伤识别随机损伤定位向量(SDLV) 弹性薄板柔度矩阵