Integrating existing liquid storage and supply tanks in buildings with tuned liquid dampers (TLDs) are significant for reducing the effective cost of TLDs. However, existing water supplement devices for fire-suppression liquid tanks may overfill with water, which leads to TLD mistuning. To overcome this problem, a passive liquid control system named TLD with a stable replenishment sub-tank system (TLD-SRS) is proposed. The system, which consists of an additional sub-tank connected to the main tank and a floating ball, replenishes liquid in the TLD automatically. The system can avoid vibration interference and maintain the normal operation of the passive replenishment system under usual wind loads. According to the studies of tuned liquid column dampers (TLCD), the proposed TLD with a stable replenishment sub-tank system (TLD-SRS) uses simple devices to ensure that the liquid level in the TLD is steady at the target liquid level with a floating ball. The TLD-SRS is verified on a large-scale TLD shaking table experiment. The overshoot, which is the percentage of liquid that exceeds the target volume of TLD is calculated during sloshing with wind loads. Compared with TLD installed with a regular liquid replenishment device, the proposed TLD-SRS significantly reduces the overshoot of liquid and acceleration on the roof of the building.

In order to study the lift coefficient and Strouhal number of high flexible structures with a circular-section under high Reynolds numbers, the wind pressure and wind speed of a 210 meter high concrete chimney were measured. On the basis of the field measured data of this study and the relevant existing research, the reasons for the significant differences in the field measured data by different scholars were compared and analyzed, the variation characteristics of parameters such as the RMS lift coefficient and Strouhal number under different Reynolds numbers and turbulence intensities were studied, and the empirical formula of lift coefficient was established. This study shows that the lift coefficient caused by turbulence is approximately 0.4 times that of along-wind turbulence destiny, and the lift coefficient caused by vortex shedding shows a trend of ‘stable-rising-decreasing-stable’ with the increase of Reynold number. The Strouhal number is mainly concentrated around 0.22 and generally independent of the turbulence intensity and the Reynold number.

A fire-suppression water tank is usually required at the top of a tall building. It would be economical to design a fire-suppression tank as a tuned liquid damper (TLD) during preliminary building design. A TLD has obvious advantages in terms of economy, maintenance, and damping efficiency with small vibrations. The sloshing nonlinearity of a TLD increases design difficulty. The purpose of this study is to investigate the nonlinear dynamic response of a large-scale TLD and provide an equivalent model for the TLD under small excitation suitable for the vibration comfort control of tall buildings. The nonlinear dynamic response was investigated through shaking table experimental results. An experiment was conducted with a TLD with a rectangular tank size of 2500 mm x 1750 mm and a sloshing period of 3.2-6.2 s. A series of TLD tests were performed with different flow-damping devices, water depths, and excitations. The time history of the water sloshing wave height was obtained using a video recognition method; the base shear force of the tank was measured simultaneously. A new nonlinear stiffness and damping model (NSD-h) was proposed that simplified the TLD as a nonlinear tuned mass damper (TMD) to predict the tank base force. In the NSD-h model, the equivalent wave height was introduced to describe the sloshing amplitude of the TLD. The nonlinear frequency and damping ratio of the TLD were calculated using the equivalent wave height. Verified in wind conditions, the NSD-h model demonstrated significantly higher accuracy than the nonlinear stiffness and damping model (NSD) with similar simple equations.

本文分析了浅水水箱调谐液体阻尼器(TLD)系统非线性晃动致刚度硬化和水深控制偏差两种导致TLD系统自振频率偏差的因素.以某250m高层建筑为研究对象,分析了这两种频率偏差因素导致的TLD系统减振率下降幅度.给出提高TLD系统阻尼比和双水箱联合控制两种提高TLD系统减振率鲁棒性的措施.结果表明,提高TLD系统阻尼比和合理设计的双水箱联合控制均可以有效提高TLD系统减振鲁棒性.当双水箱TLD系统两个水箱水深符合独立正态分布时,为达到相同的最低减振率保证率目标,设置两个水箱水深期望值0.8和1.2,比两个水箱水深期望值均为1.0,前者所需控制的水深偏差更小,水深控制难度更小.

Damage and ultimate failure of cladding elements may play an important part in the wind-resistant performance of structural system. Particularly for those claddings made from lightweight and flexible materials, they are more sensitive and vulnerable to wind excitation. This study proposes an approach of reducing the design wind loads for the local flexible cladding of structures, where the significant geometric nonlinear effect of the cladding is considered. In the light of stress equivalence principle and finite element analysis, the equivalent design wind load for the local flexible cladding is presented with consideration of reducing extreme wind pressure which is usually used for the design of rigid cladding and resulted from statistical analysis of experimental pressure measurement. In view of characteristics of wind pressure distribution on local flexible cladding units, the reduction coefficient of extreme wind pressure at varying wind directions is also given to build wind load evaluation system for the flexible cladding. The effects of wind pressure gradient and correlation on determining the design wind loads are respectively quantified by fluctuating factor and synchronous factor in order to further explore their action mechanism. Moreover, a case study is performed to examine the effectiveness and reliability of this proposed approach in actual application, where the results of extreme wind pressure, reduction coefficient and relevant influencing parameters are analyzed. It proves that this evaluation system is not limited by the external geometry of structures, and can help to optimize the wind-resistant design of the cladding economically, especially for the local flexible cladding susceptible to variation of fluctuating wind pressures.

现行《建筑结构荷载规范》(GB 50009-2012)风荷载计算公式基于规范所给定的基本振型形式进行推导,背景分量因子的部分参数则是基于规范振型直接积分获得,当实际振型与规范振型差异较大时,基于规范参数的计算风荷载可能与实际风荷载差异较大.从等效风振力法出发,针对结构沿高质量、受风面积、阻力系数不变情况,采用指数形式的振型,研究了高层及高耸建筑振型变化对顺风向风荷载的影响,并基于规范公式形式拟合了背景因子计算公式.研究表明:反映结构顶点位移的IΦ随振型指数增加而增加;但结构基底响应随着振型指数增加而减小;现行规范给定的振型函数可用指数函数替代,其中高层建筑振型指数为0.9;高耸建筑振型指数为1.5;当高层建筑振型指数低于0.9时,采用规范振型计算结果与实际结果相比偏小;当高层建筑振型指数高于0.9时,采用规范振型计算结果与实际结果相比偏大;对大部分超高层建筑,采用规范振型的顺风向风荷载比实际振型计算结果大,设计偏于安全.当高耸建筑振型指数低于1.5时,采用规范振型计算结果与实际结果相比偏小;当高耸建筑振型指数高于1.5时,采用规范振型计算结果与实际结果相比偏大.

Wind tunnel test by aero-model is an accurate way to evaluate the performance of high-flexible structures under wind load, and the fabrication of aero-model is an important step in this work. Taking a circular section industrial chimney as an example, this study introduces a new method for making the aero-model with continuous shell. The continuous model in this paper is made by DEVCON plastic steel liquid, and the main fabrication process can be briefly summarized in the following steps. Firstly, the inner mold is made with gypsum and the outer mold is carved out of Plexiglas, with the gap width between the inner and outer mold precisely designed in this step. Secondly, the DEVCON liquid is infused into the gap; and finally, the molds are removed after the glue cured, and the aero-elastic model is now complete. Structural dynamic properties, such as frequencies, mode shapes and damping ratio, were measured after making the aero-model. Test results show that the model's dynamic properties are consistent with the actual chimney. After the continuous model is made, the wind-induced response can be simulated by conducting a reasonable wind tunnel test. The advantages of the proposed method are a short fabrication period, low cost, and high precision. Moreover, this method is applicable to a variety of cross-sections of high chimneys, regardless of whether the section shape is circular or not. This study can provide a new method for the design and fabrication of continuous aero-model of high chimneys.

为了消除露井联采回填区沉降及采空区突然垮塌对上方光伏基地地基稳定性造成的安全隐患,首先采用综合物探、钻探及钻孔电视等勘查方法,查清回填区赋存状况及深部采空区范围,然后设计采用浅部回填区注浆与深部采空区注浆相结合的地基整体加固方案,优化注浆物理力学参数和施工工艺,最后采用多种方法进行注浆加固效果检测.结果表明:采用单点地震法、地质雷达法和瞬变电磁法的综合物探勘查方法并布置钻探验证孔,可查清浅部回填区与深部空洞分布范围;浅部回填区采用1:1为主的单液水泥浆,深部采空区采用1:0.3:0.9为主的水泥粉煤灰浆液,经过优化注浆物理力学参数和施工工艺,可以实现露井联采回填区和采空区的注浆加固;采用物探、钻孔取芯漏失液观测、波速测试以及地表沉降观测的方式进行注浆效果检测,实现浅部、深部注浆效果的全覆盖检测,通过检测得到回填区和采空区空洞、裂隙注浆效果良好,消除了光伏地基隐患.

为了评估煤矸石回填区光伏建设场地地基稳定性,在分析煤矸石回填层变形特性的基础上,提出了弹性力学模型和开尔文模型相结合计算煤矸石回填层地表残余沉降变形的技术思路.研究结果表明,考虑回填时间和回填厚度因素的煤矸石回填层残余沉降变形计算方法简单实用,能够满足工程需要,计算结果可为光伏设备基础设施建设提供设计依据.

回顾了国家标准《建筑结构荷载规范》编制修订的发展历程,总结归纳各版本的主要内容及技术特点.该规范自20世纪50年代诞生以来共有5个主要的修订版本.1954年发布的最初版本(结规-1-54)以引进吸收国外标准为主.我国自主研编的1974年版本(TJ 9-74)内容基本本地化且较为完整.1987年版本(GBJ 9-87)采纳基于概率的极限状态设计方法,并进行了大规模的荷载调查和活荷载组合方法研究,使本标准进入国际先进标准的行列.现行的2012年版本(GB 50009-2012)不仅针对大跨和超高层建筑结构设计需求补充完善了大量风荷载、雪荷载内容,还新增了温度作用和偶然荷载,规范的适应性和技术水准显著提升.根据国家工程标准改革的部署,该规范内容将纳入正在编制中的全文强制规范中,适用范围扩展到工程结构,取值水准也将适当提高,以提升我国的结构可靠性水准,并与国际标准接轨.

采煤沉陷区上兴建光伏设备不可避免的会存在地表变形造成设备的损坏问题.为了保证光伏设备的安全运行,光伏设备下的采空区进行治理是必须的.通过对各种采空区治理方法的对比分析,认为注浆充填法是采空区治理的一种有效的方法.结合曹家沟汇集站的情况,提出合理治理角,确定治理范围,在保证汇集站的安全运行条件下又减少了工程造价.

回顾了中国建筑科学研究院近年来在风工程领域取得的重要研究进展.风荷载研究方面,在提出风振计算广义坐标合成法基础上,建立了基于响应时程的结构等效静风荷载计算体系,开展了复杂高层建筑风致振动的系统研究,探明了高层建筑弯扭耦合风振响应的基本规律,提出了高层建筑横风向响应的反应谱方法.风环境研究方面,提出了平衡边界层新的理论解释和数学模型,以及植被和绿化带数值模拟的附加源/汇数学模型.提出了考虑地貌修正的气象资料修正方法,建立了基于日最大风速记录的风环境评估体系,开展了列车风和烟囱效应等特殊风环境的研究.雪荷载研究方面,开展了雪荷载风洞试验和数值模拟技术的研究,提炼了雪荷载风洞试验模拟的核心相似参数,阐明了风致积雪飘移的流动机理,开发了CFD数值模拟的相关程序.团队研究成果在重大工程中得以广泛应用,部分成果被纳入国家和行业标准规范.

In order to ensure photovoltaic facilities good condition ,it is necessary to reinforce the coal mine goal below the base .Taking 110 kV collecting station as an example ,the stability of the foundation is evaluated based on the analysis of the coal mine goal .According to the geological conditions and the evaluation results of the stability of goaf ,the grouting technology is adopted to reinforce the goaf below the collecting station .The paper puts forward the grouting treatment scheme .After grouting ,the reinforcement effect is tested .The results show that the grouting reinforcement scheme is reasonable and effective .

To ensure the safety of the construction of photovoltaic plant in coal mining subsidence area,it is very necessary to carry out the evaluation of foundation stability and goaf treatment.Taking the photovoltaic project in Datong city of Shanxi province as an example,project profile for the construction of photovoltaic plant in subsidence area was introduced.Based on the theory and practice of coal mining subsidence and coal mines in Datong city,according to the demand for different stages of photovoltaic project,the responding foundation stability evaluation were finally carried out.Some technical measures for goaf treatment were proposed for the construction of photovoltaic plant.

结合风洞同步测压试验,利用高效的广义坐标合成法分析了某连体高层空中连廊的风振特性.采用塔楼-连廊的整体结构模型进行计算,可充分考虑塔楼运动对连廊的影响.计算结果表明,连廊的运动主要是由于塔楼主体运动引起的,连廊自身风压对其风致响应的贡献极小;两座塔楼的相对运动与横梁的轴力有很强的相关性,是造成横梁受拉压的主要因素.分析表明,不管连廊与主体之间采用何种连接方式,都不宜将空中连廊作为独立结构计算其风振特性.采用的整体分析方法对于分析连体高层主体及连廊的风致振动具有普遍的适用性.

Across wind load,torsional wind load and interference effect from next buildings may induce great responses on high-rise buildings. The paper introduced characters of wind loads on high-rise buildings, and countermeasures are recommended according to control responses. Research and result of project case showed that modification of building shape and dynamic property were effective methods to improve wind environment and decease wind induced responses of high-rise buildings.

采用风洞试验方法,对北京某商业中心行人风环境进行研究,通过对行人活动区域测点风速的统计分析,得到该区域16个风向角下的行人高度风速分布.结合气象资料,利用针对不同行人活动类型的大概率发生事件的行人风环境评估标准,对该商业中心的风环境品质进行定量评估,并对可能造成行人不舒适或危险的区域提出改善建议.

通过风洞试验和数值模拟,对成都来福士广场建筑群分别进行了表面风压测试试验及行人高度风环境的模拟研究.通过刚性模型测压试验得到了建筑群复杂外形的表面平均和极值风压分布,可用于主体结构设计和幕墙设计;通过对行人高度风环境的数值模拟研究得到了建筑群间不同区域的行人高度风速分布,并结合研究结果给出改善建议.

基于CFD数值模拟方法,采用“动网格”技术,对列车高速过站(80 km/h)风环境进行数值模拟,给出高速列车开始驶入、完全驶入和驶离车站时,站台区域行人高度风速变化情况.在站台行人区域布置63个风速测点,对列车风的影响进行定量评估,并结合评定人员活动的风环境舒适度评估标准,划定站台区域人员活动安全和舒适范围,为站台区域设计提供建议.

对深圳湾体育中心进行了测压试验、风环境试验和风振响应分析.着重研究了屋盖悬挑部分上、下表面脉动风压的相关性,指出相关系数对合压力脉动强度有重要影响.并通过对比测压试验,评估了周边建筑对屋盖平均风压和脉动风压分布的影响.周边建筑的存在使得平均风压幅值降低,而脉动风压明显增大.根据风环境试验结果,分析了体育场内部风场的分布,对当地主导风向进行评价,并提出针对性建议.最后,基于同步测压试验结果,对屋盖结构进行了基于时程方法的风致响应计算,得到了动力风荷载作用下的位移响应特征.