Vibration Control of a High-Rise Building Structure:Theory and Experiment

In this study,an innovative solution is developed for vibration suppression of the high-rise building.The infinite dimensional system model has been presented for describing high-rise building structures which have a large inertial load with the help of the Hamilton’s principle.On the basis of this system model and with the use of the Lyapunov’s direct method,a boundary controller is proposed and the closed-loop system is uniformly bounded in the time domain.Finally,by using the Smart Structure laboratory platform which is produced by Quancer,we conduct a set of experiments and find that the designed method is resultful.

Safety analysis of optimal outriggers location in high-rise building structures

This paper presents the restraining moments of outriggers acting on the core wall and the equation of the horizontal top deflection based on a simplified outrigger model. The deformation compatibility conditions between outriggers and core wall as well as the finite rigidities of outriggers are also considered. One case study was carried out to analyze the horizontal top deflection and the mutation of the restraining moments caused by the variation of outrigger location. The results showed that the method adopted in the paper is simple and reasonable. Some conclusions are valuable to the safety design of high-rise building structures.

Research of CBR, DM and smart algorithms based design methods for high-rise building structure form-selection

First, the high-rise building structure design process is divided into three relevant steps, that is, scheme generation and creation, performance evaluation, and scheme optimization. Then with the application of relational database, the case database of high-rise structures is constructed, the structure form-selection designing methods such as the smart algorithm based on CBR, DM, FINS, NN and GA is presented, and the original forms system of this method and its general structure are given. CBR and DM are used to generate scheme candidates; FINS and NN to evaluate and optimize the scheme performance; GA to create new structure forms. Finally, the application cases are presented, whose results fit in with the real project. It proves by combining and using the expert intelligence, algorithm intelligence and machine intelligence that this method makes good use of not only the engineering project knowledge and expertise but also much deeper knowledge contained in various engineering cases. In other words, it is because the form selection has a strong background support of vast real cases that its results prove more reliable and more acceptable. So the introduction of this method provides an effective approach to improving the quality, efficiency, automatic and smart level of high-rise structures form selection design.

Discussion on seismic design of high-rise building structure in China

With the rapid development of China＇s economy, the modernization drive and the process of urbanization continue to advance, land for urban construction is becoming more and tenser and land prices are rising steadily, there are more and more high-rise buildings, its density is also increasing. With the increasing number trend of high-rise building development, anti-seismic building requirement as an important part of architectural design is worthy of our exploration and study. Seismic resistance has become an important subject of engineering design. This paper will discuss the technical principle of seismic design in building structure design, so as to optimize the seismic design of high-rise building structure better.

Quantitative investigation on collapse margin of steel high-rise buildings subjected to extremely severe earthquakes

Reponses of structures subjected to severe earthquakes sometimes significantly surpass what was considered in the design.It is important to investigate the failure mechanism and collapse margin of structures beyond design,especially for high-rise buildings.In this study,steel high-rise buildings using either square concrete-filled-tube（CFT） columns or steel tube columns are designed.A detailed three-dimensional（3 D） structural model is developed to analyze the seismic behavior of a steel high-rise towards a complete collapse.The effectiveness is verified by both component tests and a full-scale shaking table test.The collapse margin,which is defined as the ratio of PGA between the collapse level to the design major earthquake level（Level 2）,is quantified by a series of numerical simulations using incremental dynamic analyses（IDA）.The baseline building using CFT columns collapsed with a weak first story mechanism and presented a collapse margin ranging from 10 to 20.The significant variation in the collapse margin was caused by the different characteristics of the input ground motions.The building using equivalent steel columns collapsed earlier due to the significant shortening of the locally buckled columns,exhibiting only 57% of the collapse margin of the baseline building.The influence of reducing the height of the first story was quite significant.The shortened first story not only enlarged the collapse margin by 20%,but also changed the collapse mode.

Structural form selection of the high-rise buildingwith the improved BP neural network

As civil engineering technology development,the structural form selection is more and more critical in design of high-rise buildings.However,structural form selection involves expertise knowledge and changes with the environment which makes the task arduous.An approach utilizing improved back propagation(BP)neural network optimized by the Levenberg-Marquardt(L-M)algorithm is proposed to extract the main controlling factors of structural form selection.Then,an intelligent expert system with artificial neural network is constructed to design high-rise buildings structure effectively.The experiment tests the model in 15 well-known architecture samples and get the prediction accuracy of 93.33%.The results show that the method is feasible and can help designers select the appropriate structural form.

Study on Steel Bar Construction Technology of Frameshear Wall in High-Rise Buildings

The development of the construction sector is rapidly growing,which induce competition at global level.In order to achieve the current economic development,more high-rise buildings construction projects were commenced without considering importance of the land to human and other living organism.On the other hand,the quality and safety aspect of the engineering technology used must be analyzed carefully and to be the primary aim for engineers to reduce any risk of harm in future.Many of the high-rise buildings in China consist of a frame or skeleton of reinforced concrete wall which need to be strengthened with shear walls to improve the stability and safety of the structures.According to practical work experience and relevant theoretical knowledge,the researcher introduced the reinforcement construction technology of frame-shear wall for high-rise buildings in depth from aspects like the arrangement of steel bar,construction preparation,steel bar anchorage,precautions to follow for the related work in future.

Discussion on Construction Technology and Welding Deformation of High-Rise Steel Frame Structure

Because of urbanization,land resources in China’s cities has become increasingly scarce.Therefore,modern buildings are becoming taller,making high-rise steel frame structures the new favorite of the construction industry.However,the construction of high-rise steel frame structures requires advanced technology.If the construction technology is effectively implemented and the welding techniques of the construction personnel align with the requirements for high-rise steel frame structures,it can help mitigate deformations in the steel structure,thus preserving the overall construction quality of high-rise steel frame structures.To enhance the applicability of steel frame structures in high-rise buildings,this paper focuses on analyzing the optimization path for the construction process of high-rise steel frame structures.It introduces a tailored approach to control welding-induced deformations in steel frame structures,aiming to make a valuable contribution to the advancement of China’s construction industry.

INVESTIGATION OF LOW CYCLE FATIGUE BEHAVIOROF BUILDING STRUCTURAL STEELS UNDEREARTHQUAKE LOADING

Based on the failure model of building structural steels under earthquake loading, the low cycle fatigue test at constant strain, the stochastical fatigue test under real earthquake load spectrum and the structural fatigue test are carried out. The experimental results show that microalloying of V Ti and Nb can improve the anti-seismic propersties of steel bars. In the high strain and shori life range, both the static strength and ductility of steels are very important to increasing the low cycle fatigue resistance of steels.

Optimum structural design of full-scale steel buildings using drift-tribe-charged system search

In this paper,the potential of utilizing improved metaheuristic approaches in optimal design of building structures is concerned.In this regard,the drift-tribe-charged system search algorithm is proposed that the position and velocity updating processes of the charged system search is developed by implementing the mathematical presentation of the free-electron model utilized for metal conductors.In addition,the searching phase of the developed algorithm is also divided into three separate phases in order to improve the convergence capability of the algorithm.By means of these modifications,the exploitation and exploration rates of the standard algorithm are enhanced.In order to determine the ability of the proposed improved metaheuristic method considering some complex optimization problems,a 10-story steel building structure with 1026 structural members alongside a 60-story structure with 8272 members are utilized as numerical examples.The overall capability of the developed metaheuristic approach is compared with other metaheuristics.A total number of 30 independent runs have been conducted for each of the standard and proposed methods while a statistical analysis is also conducted for comparative purposes.The obtained optimum results demonstrated that the proposed metaheuristic approach is capable of preparing better outcomes than other metaheuristics.

High-Rise Residential Reinforced Concrete Building Optimisation

In the last few decades structure optimisation has become a main task in a civil engineering project. As a matter of fact, due to the complexity and particularity of every structure, the great amount of variables and design criteria to considerate and many other factors, a general optimisation’s method is not simple to formulate. As a result, this paper focuses on how to provide a successful optimisation method for a particular building type, high-rise reinforced concrete buildings. The optimization method is based on decomposition of the main structure into substructures: floor system, vertical load resisting system, lateral load resisting system and foundation system;then each of the subsystems using the design criteria established at the building codes is improved. Due to the effect of the superstructure optimisation on the foundation system, vertical and lateral load resisting system is the last to be considered after the improvement of floor. Finally, as a case example, using the method explained in the paper, a 30-story-high high-rise residential building complex is analysed and optimised, achieving good results in terms of structural behaviour and diminishing the overall cost of the structure.

Research on ETABS Steel Tower atop Building Structural System

Equipping steel tower atop building structural system at the top of high-rise buildings is applied increasingly. However, the earthquake disasters indicate that under seismic effect, the tower on the roof reacts strongly to the earthquake, and the gazebo is damaged greatly under the condition that major structure has no earthquake damage. Based on analyzing the characteristics and application methods of ETABS software, for engineering projects, the paper uses ETABS software and simplified calculation method to calculate and make comparison analysis on steel tower atop building structure. The analysis results indicate that the method established in the paper has higher accuracy, which can meet the engineering requirements.

Research and Implementations of Structural Monitoring for Bridges and Buildings in Japan

This paper provides a review on the development of structural monitoring in Japan, with an emphasis on the type, strategy, and utilization of monitoring systems. The review focuses on bridge and building structures using vibration-based techniques. Structural monitoring systems in Japan historically started with the objective of evaluating structural responses against extreme events. In the development of structural monitoring, monitoring systems and collected data were used to verify design assumptions, update speci cations, and facilitate the ef cacy of vibration control systems. Strategies and case studies on monitoring for the design veri cation of long-span bridges and tall buildings, the performance of seismic isolation systems in building and bridges, the veri cation of structural retro t, the veri cation of structural control systems (passive, semi-active, and active), structural assessment, and damage detec- tion are described. More recently, the application of monitoring systems has been extended to facilitate ef cient operation and effective maintenance through the rationalization of risk and asset management using monitoring data. This paper also summarizes the lessons learned and feedback obtained from case studies on the structural monitoring of bridges and buildings in Japan.

The Structural Behavior of Low/Medium/High Rise Concrete Office Buildings in Kuwait

The main concern of this paper is to provide an extensive study for the structural behavior of low/medium/high rise office buildings aiming to deepen structure and architect designers understanding for such type of buildings. The study is performed on reinforced concrete and emphasized only on Kuwait city conditions for wind. Regular layout plan building with different heights ranging from five to fifty typical office stories are investigated in this study. Three dimensional finite element techniques through ETABS software are used in conducting analysis for structures presented here-in. A serviceability study is performed to ensure that buildings have sufficient stability to limit lateral drift and peak acceleration within the acceptable range of occupancy comfort. In addition, an ultimate strength study is carried out to design and verify that all the structural elements are designed to withstand factored gravity and lateral loadings in a safe manner according to the international building codes. The building slenderness ratio and the building core size and location are the studied parameters since they are the key drivers for the efficient structural design. Analysis results are presented and discussed and finally conclusions are summarized as guidelines for designers of concrete office buildings in Kuwait.

基于Tekla Structures的三维仿真技术应用研究

【目的】针对复杂的装配式钢结构建筑,为了保证工程质量,提高施工效率,需要对三维仿真技术的工程应用进行研究。【方法】以郑州市某装配式钢结构工程为例,利用Tekla Structures内置的三维碰撞分析模块,对碰撞问题进行优化,并进行精细化三维仿真模拟,对屋面工程的第一榀~第四榀主桁架、次桁架的施工全过程进行仿真分析,确定合理的施工方案。【结果】发现一处钢梁加劲肋与水平支撑的碰撞问题,并进行了优化设计。通过三维仿真模拟,确定了合理的屋面桁架施工方案,保证了施工质量,明显加快了工程进度。【结论】三维仿真技术对于装配式建筑的发展具有重大意义,在施工过程中应加强三维碰撞分析、三维仿真模拟,从而确保工程质量和工期进度,研究成果可为类似工程的三维仿真技术应用提供一定的参考。

Elastic-plastic study on high building with SRC transferring story

A new type of transferring structure for steel reinforced concrete (SRC) beams is used in high building. The pushover analysis method was used to study the failure mechanism and ductility of SRC transferring structure through consulting pseudo-static test results for the structure. And, the occurrence order and position of the plastic hinge, the weak story and seismic capacity of high building with SRC transferring story were also studied through consulting shaking table test results for the high building, showing that the seismic behavior of high building with SRC transferring story is good.

Recent progress of seismic research on tall buildings in China Mainland

As a result of rapid economic growth and urbanization in the past two decades,many tall buildings have been constructed in China Mainland,offering researchers and practitioners an excellent opportunity for research and practice in the field of structural engineering. This paper reviews progress by researchers throughout China Mainland on the seismic research of tall buildings,focusing on three major topics that impact the seismic performance of tall buildings. These are:(1) new types of steel-concrete composite structural members such as steel-concrete composite shear walls and columns,(2) earthquake resilient shear wall structures such as shear walls with replaceable structural components,self-centering shear walls and rocking walls,and(3) performance-based seismic design,including seismic performance index,performance level and design method. The paper concludes by presenting future research needs and directions in this field.

Decentralized damage diagnostic technique for tall buildings using VARMAX model

Civil infrastructure,especially buildings,are becoming more slender,tall,and multipurpose,creating a need to continuously monitor their health to ensure the safety and security of human lives and assets.While the majority of structural health monitoring techniques use measurements from the entire structure,in this study,an output-only damage diagnostic technique using a decentralized concept(subdomain-based)for tall buildings and employing a vector form of the autoregressive moving average with exogenous input(VARMAX)model is proposed,which offers reduced instrumentation and data handling requirements.Unlike other decentralized approaches,this technique predicts more than one DOF at a time so the number of subdomains required for the diagnosis of the complete structure is minimized.The proposed subdomain-based damage diagnostic algorithm works with ambient loads and does not require any correlated numerical models since it is solely based on measured data.The proposed algorithm can identify the time instant of damage,spatial location(s)and characterize the damage intensity.Efforts have been made to account for confounding factors such as environmental and operational variabilities separate from measurement noise to avoid false positive alarms.The effectiveness of the proposed technique is illustrated using synthetic time history responses from a twenty-story framed structure under ambient loading and an experimental study on a ten-story framed structure.Both numerical and experimental investigations confirm the effectiveness of the method and its robustness to environmental/operational variabilities and measurement noise.

基于钢结构BIM模型的结构分析数据转换和软件开发

为解决当前在钢结构建筑信息模型(building information modeling,BIM)与结构分析模型之间进行数据转换时存在的关键技术问题,本文在分析工业基础类(industry foundation classes,IFC)标准表达方法的基础上,以ABAQUS为结构分析平台,开发了钢结构BIM模型数据转换算法,运用C#语言和Xbim工具包,实现了结构构件信息提取、构件空间位置调整和分析数据自动添加,并形成了相应的转换软件;通过钢框架结构实例分析验证了该软件的可靠性和准确性,并将其应用于安阳市游客集散中心的BIM模型转换和结构分析。结果表明,所开发的算法和软件解决了生成的结构分析模型节点不连接和人工添加分析数据工作量大等问题,实现了BIM中的钢结构设计模型或深化设计模型向ABAQUS结构分析模型数据的准确转换。与传统的在ABAQUS中直接建立结构分析模型相比,本文提出的方法能大大提高复杂钢结构的结构分析建模速度和效率。

大型履带吊上楼面板施工过程有限元分析

珠海某项目由框架、核心筒及双层交叉桁架结构体系组成,采用在地下室顶板上铺设路基箱的加固方式,部分构件先地面拼装再吊装等施工工艺,同时对履带吊行走路线进行严格的规划。在现有结构上进行钢结构吊装,对下部混凝土结构影响较大,采用MIDAS GEN有限元分析软件对下部混凝土结构的裂缝和应力变化情况进行有限元分析,模拟履带吊全施工过程。分析结果表明:在地下室顶板上铺设路基箱的加固方式,可以有效降低下部混凝土结构的最大变形及应力,满足国家规范要求。