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Optimal design and dynamic impact tests of removable bollards

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 793-802页

作者： Chen Suwen Liu Tianyi Li Guoqiang Liu Qing sun jianyun State Key Laboratory for Disaster Reduction in Civil Engineering Shanghai 200092China College of Civil Engineering Tongji UniversityShanghai 200092China China State Construction Engineering Corp.Ltd.Beijing 101300China

Anti-ram bollard systems, which are installed around buildings and infrastructure, can prevent unauthorized vehicles from entering, maintain distance from vehicle-borne improvised explosive devices （VBIED） and reduce the corresponding damage. Compared with a fixed bollard system, a removable bollard system provides more flexibility as it can be removed when needed. This paper first proposes a new type of K4-rated removable anti-ram bollard system. To simulate the collision of a vehicle hitting the bollard system, a finite element model was then built and verified through comparison of numerical simulation results and existing experimental results. Based on the orthogonal design method, the factors influencing the safety and economy of this proposed system were examined and sorted according to their importance. An optimal design scheme was then produced. Finally, to validate the effectiveness of the proposed design scheme, four dynamic impact tests, including two front impact tests and two side impact tests, have been conducted according to BSI Specifications. The residual rotation angles of the specimen are smaller than 30~ and satisfy the requirements of the BSI Specification.

关键词： removable anti-ram bollards optimal design orthogonal design method dynamic impact test

Effects of Boundary Conditions on the Design of Anti-Ram Bollards

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Transactions of Tianjin University 2008年第5期14卷 384-386页

作者： LIU Chunlin LI Guoqiang PHANG Siew Kheong sun jianyun K＆C Protective Technologies Pte Ltd. 1 59361 Singapore School of Civil Engineering Tongji University Shanghai 200092 China

Anti-ram bollards used in perimeter protection are tested to meet performance requirements of established standards such as the US Department of State Specification SD-STD-02.01. Under these standards, tests are conducted in prescribed conditions that should be representative of the service installation. In actual project, conditions encountered on site may vary from the test environment and it would be expensive and time consuming to validate each deviation with a physical test. High-fidelity physics-based (HFPB) finite element modeling can provide precise simulations of the behavior of anti-ram bollards. This paper presents the use of HFPB finite element modeling, using LS-DYNA, in an actual project to evaluate the performance of an anti-ram bollard design subjected to various boundary conditions representing the physical conditions encountered on site. The study shows that boundary conditions can have a significant influence on the performance of the anti-ram bollards. This suggests that anti-ram bollards must be designed and engineered according to actual conditions that are found on site. It also shows that HFPB modeling can be an effective tool that supplements physical testing of anti-ram bollards.

关键词： anti-ram bollards perimeter protection high-fidelity physics-based modeling LS- DYNA boundary conditions

Introduction to Enhanced Protective Film Systems

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Transactions of Tianjin University 2008年第B10期14卷 491-494页

作者： LIU Chunlin DAVID Palermo LI Guoqiang sun jianyun CHEN Suwen K＆C Protective Technologies（KCPT） Singapore 1 59361 Colleague of Civil Engineering Tongji University Shanghai 200092 China Sherwin-Williams Company South Holland IL 60473 USA

An explosive blast mitigation alternative has increased the safety of structures by using " catcher" systems. These systems " catch" or repel the failure of the window or in-fill wall pro-tecting life and property from ballistic shards or fragments. They can be designed to be stand-alone in new construction and structural retrofits or used to augment structural hardening tech-niques. Cables, fabrics, and thin gauge sheet steel are examples of catcher systems used in the past. A new and evolving category of catcher systems are based on polymeric materials that can be used for both wall and window upgrades. These products are a proven blast mitigation concept and K&C Protective Technologies Pte Ltd (KCPT) together with Sherwin-Williams(SW) use KCPT′s blast engineering capacity and SW′s material engineering principles to create engineered systems for even greater in-use performance.

关键词： explosion blast mitigation catcher system protective film systems

Hybrid Post-Processing Procedure for Displacement-Based Plane Elements

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Journal of Applied Mathematics and Physics 2013年第6期1卷 15-19页

作者： Xiaoming Chen Song Cen jianyun sun Yungui Li China State Construction Technical Center Beijing China Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing China

In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produced by wall holes and the loss of precision induced by using differential method to derive strains, the displacement-based elements cannot always present accuracy enough for design. In this paper, the hybrid post-processing procedure based on the Hellinger-Reissner variational principle is used for improving the stress precision of two quadrilateral plane elements. In order to find the best stress field, three different forms are assumed for the displacement-based plane elements and with drilling DOF. Numerical results show that by using the proposed method, the accuracy of stress solutions of these two displacement-based plane elements can be improved.

关键词： Finite Element Displacement-Based Plane Element Hybrid Post-Processing Procedure

A Parallel FEA Computing Kernel for Building Structures

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Journal of Applied Mathematics and Physics 2013年第6期1卷 26-30页

作者： Jin Duan Yungui Li Xiaoming Chen Hu Qi jianyun sun China State Construction Technical Center Beijing China

With the rapid development of high-rise buildings and long-span structures in the recent years, high performance com- putation (HPC) is becoming more and more important, sometimes even crucial, for the design and construction of com- plex building structures. To satisfy the engineering requirements of HPC, a parallel FEA computing kernel, which is designed typically for the analysis of complex building structures, will be presented and illustrated in this paper. This kernel program is based on the Intel Math Kernel Library (MKL) and coded by FORTRAN 2008 syntax, which is a parallel computer language. To improve the capability and efficiency of the computing kernel program, the parallel concepts of modern FORTRAN, such as elemental procedure, do concurrent, etc., have been applied extensively in coding and the famous PARDISO solver in MKL has been called to solve the Large-sparse system of linear equations. The ultimate objective of developing the computing kernel is to make the personal computer have the ability to analysis large building structures up to ten million degree of freedoms (DOFs). Up to now, the linear static analysis and dynamic analysis have been achieved while the nonlinear analysis, including geometric and material nonlinearity, has not been finished yet. Therefore, the numerical examples in this paper will be concentrated on demonstrating the validity and efficiency of the linear analysis and modal analysis for large FE models, while ignoring the verification of the nonlinear analysis capabilities.

关键词： High Performance Computing Finite Element Analysis Building Structure PARDISO

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滑坡涌浪对坝面冲击压力的影响因素研究

水利学报 2018年第2期49卷 232-240页

作者：李静陈健云徐强孙迅大连理工大学建设工程学部辽宁大连116024

库区边坡在强震、暴雨等作用下发生的滑坡失稳破坏会对挡水大坝形成巨大的涌浪冲击作用。本文针对库区滑坡涌浪对坝面的冲击压力问题,采用光滑粒子水动力学(SPH)方法研究了涌浪生成传播过程以及坝面涌浪冲击压力的分布形式,分析了滑坡... 详细信息

库区边坡在强震、暴雨等作用下发生的滑坡失稳破坏会对挡水大坝形成巨大的涌浪冲击作用。本文针对库区滑坡涌浪对坝面的冲击压力问题,采用光滑粒子水动力学(SPH)方法研究了涌浪生成传播过程以及坝面涌浪冲击压力的分布形式,分析了滑坡体宽度、入水速度以及库区水深等因素对滑坡涌浪波高、坝面冲击压力的影响。结果表明,随着滑坡体宽度的增加,最大浪高降低,但是稳定波高增加,坝面冲击压力增大;随着滑坡入水速度的增加,波浪高度增加,但当入水速度增加到一定程度后,坝面冲击压力变化不明显;随着库区水深的增加,首浪高度降低,坝面最大冲击压力以及距离水面的相对作用位置基本不变。

关键词： SPH方法滑坡涌浪混凝土坝冲击压力

基于可变下垂线的变速风电机组参与微网频率调节控制

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中国电机工程学报 2016年第24期36卷 6751-6758页

作者：由蕤柴建云孙旭东青岛大学自动化与电气工程学院山东省青岛市266071 电力系统及发电设备控制和仿真国家重点实验室(清华大学) 北京市海淀区100084

随着风电在电网中所占比例的提高,当电网频率变化过大时希望风电机组改变输出功率参与电网频率调节,改善频率的动态特性。为了应用电力系统中广泛采用的有功功率–频率下垂控制策略,依据风电机组输出功率和微网频率为风电机组参与频率... 详细信息

随着风电在电网中所占比例的提高,当电网频率变化过大时希望风电机组改变输出功率参与电网频率调节,改善频率的动态特性。为了应用电力系统中广泛采用的有功功率–频率下垂控制策略,依据风电机组输出功率和微网频率为风电机组参与频率调节构筑下垂线,当风速变化引起风电机组输出功率变化时下垂线随之改变。微网频率在正常范围内波动时风电机组采用常规最大功率点跟踪或者限功率模式运行,频率变化过大时风电机组切换至频率支撑控制模式,频率支撑期间风电机组输出功率目标值基于构筑的下垂线根据微网频率计算求得,频率支撑结束后,通过逐渐改变风电机组输出功率使机组恢复至频率支撑前的正常运行模式。采用HAWC2和MATLAB/Simulink搭建包含变速风电机组的集成仿真模型,仿真结果对所提出控制策略的有效性进行验证,并且对执行提出的控制策略对风电机组结构载荷的影响进行分析。

关键词：变速恒频风电机组微网可变下垂线频率支撑频率动态特性

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分离式型钢混凝土柱抗震性能试验研究

建筑结构学报 2024年第3期45卷 123-135页

作者：赵航黄刚范峰包联进孙建运孙飞飞中建工程产业技术研究院有限公司北京101300 哈尔滨工业大学黑龙江哈尔滨150001 同济大学土木工程学院上海200092 华东建筑设计研究院有限公司上海200011

实腹式型钢混凝土柱被广泛应用于超高层建筑的巨型柱构件中。由于截面巨大和吊装额度限制,实腹式型钢柱段内的多条现场焊缝对巨柱的整体性和延性造成不利影响。为解决这一问题,采用彼此独立的型钢替换实腹式型钢,增加起吊段的长度,从而... 详细信息

实腹式型钢混凝土柱被广泛应用于超高层建筑的巨型柱构件中。由于截面巨大和吊装额度限制,实腹式型钢柱段内的多条现场焊缝对巨柱的整体性和延性造成不利影响。为解决这一问题,采用彼此独立的型钢替换实腹式型钢,增加起吊段的长度,从而达到减少柱段内型钢焊缝的目的。为研究分离式型钢混凝土柱的抗震性能,对实腹式和分离式型钢混凝土柱试件进行拟静力加载,分析试件在轴力和弯矩共同作用下的承载能力、变形能力、耗能性能和刚度退化。试验结果显示:分离式型钢试件的最大水平剪力和极限变形能力与实腹式型钢试件基本相同,且具有良好的滞回耗能性能;分离式型钢试件在达到峰值剪力后抗侧刚度并未大幅衰减;在偏心率达到20%时,分离式型钢试件的截面应变分布基本满足平截面假定。

关键词：型钢混凝土柱分离式型钢拟静力试验抗震性能平截面假定

爆炸冲击荷载作用下SRC柱等效单自由度模型

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振动与冲击 2007年第6期26卷 82-89页

作者：孙建运李国强陆勇中建八局技术中心上海200135 同济大学土木工程学院南洋理工大学土木与环境工程学院新加坡639798

爆炸冲击荷载作用下结构构件的反应分析方法常用的是等效单自由度模型,在现有的有关资料中,等效单自由度模型主要用于钢筋混凝土构件和钢构件。等效单自由度模型的关键是确定等效弹性位移、破坏位移和屈服强度。以通用有限元分析软件LS-... 详细信息

爆炸冲击荷载作用下结构构件的反应分析方法常用的是等效单自由度模型,在现有的有关资料中,等效单自由度模型主要用于钢筋混凝土构件和钢构件。等效单自由度模型的关键是确定等效弹性位移、破坏位移和屈服强度。以通用有限元分析软件LS-DYNA为基础,研究了钢骨混凝土(SRC)柱在爆炸冲击荷载作用下的反应特征,确定出了等效单自由度模型的等效弹性位移和破坏位移;以常规SRC柱设计理论为基础,提出了等效单自由度模型的等效屈服强度计算公式。最后用所建立的等效单自由度模型和LS-DYNA软件分别对8根SRC柱共48种爆炸冲击荷载工况进行对比分析,验证了所提出的等效单自由度模型。

关键词：爆炸钢骨混凝土柱等效单自由度模型