摘要：Global failure mechanism, i.e., the strong-column weak-beam mechanism, can provide higher total energy dissipation capacity with less ductility demand on components than other failure modes, and results in a more uniform story drift distribution and higher resistance to earthquake loads at the system level. However, the current code-based elastic design method cannot guarantee the global failure mechanism of frame structures under severe earthquakes. In this paper, a simple, but practical design procedure is proposed to ensure the global failure mechanism of reinforced concrete(RC) frame structures by redesigning the columns using the column tree method(CTM). CTM considers the yield limit state of all beams and column bases. The code-based design is firstly carried out to determine the section information of all beams and base columns. Then, the internal force demands applied on the column tree can be derived. Lastly, the column moments, shear forces and axial forces are determined according to the free-body diagram of CTM to finish the column redesign. Two RC frame structures with 6 and 12 stories are illustrated to verify the design procedure. The analytical results demonstrate the proposed approach can realize the global failure mechanism.

摘要：In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed： （1） active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; （2） the linear quadratic regulator （LQR）-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and （3） the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called ＂design principle＂. The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the c

摘要：Wind loading is one of the most significant factors in civil engineering that influences the structural design *** this paper,a group of manufacturing equipments for downburst simulation based on impinging jet model was developed for investigating the wind loads on structures:including the centrifugal air bellows to generate airflow,a movable platform to realize multiple locations of the building and a freely rotatable turntable to implement alterable building *** of transducers were used to measure the wind action on all surfaces of the *** pressure coefficients calculated from the observed data were utilized to evaluate the downburst wind *** distributions on three prism-shaped building models with different placements and angles were investigated to obtain the maximum wind action and mean pressure *** results showed that the maximum pressure coefficient would reach 1.0 on the top surface if the downburst just broke out over the *** that the building was in the developing field of the downburst,the top and the front surfaces would be under high wind pressure and only the back surface would endure wind *** the downdraft happens away from the prismatic building,all surfaces,except the front surface,would subject to suction with different *** was also found that the pressure coefficient on the right surface would get its negative peak at first and then go straight up to 0.6 as the angle changed from 0°to 45°and the wind pressure on the front surface would decrease slightly through the whole *** assertive results provide elemental data for structural wind-resistant design in civil engineering for the downburst-prone areas.

摘要：Based on the principle of turned mass damper(TMD) systems,the conceptual design of semi-submersible platform with a moveable heave-plate(MHS) has been put *** heave motion response amplitude operator(RAO) and viscous damping of the MHS platform are calculated by iteration,and the coupling stiffness between the MHS hull and the heave-plate is optimized to decrease the maximum heave motion response of the MHS hull under 10-year survival conditions in the South China *** nu-merical results indicate that the heave motion RAO of the MHS hull can be decreased in the range of predominant wave frequencies,which may provide some reference to the heave motion control of offshore platforms.

摘要：采用“斜拉桥结构健康监测系统的设计与实现(I)-系统设计”中所建立的设计方法,分别为两座大型斜拉桥设计并实现长期实时健康监测系统和定期实时健康监测系统:滨州黄河公路大桥长期实时健康监测系统和哈尔滨松花江大桥定期实时健康监测系统。研究两座大型斜拉桥结构健康监测系统的总体设计方案、子系统的设计方案和硬软件设备及其实现、系统的集成技术及其实现方法;分析两套健康监测系统在成桥试验和运营中监测的桥梁结构荷载和静动力反应。结果表明,两座斜拉桥结构健康监测系统均能协调运行,实现了预期设计功能;系统中布设的光纤光栅应变和温度传感器测试精度高、耐久性好、抗电磁干扰性能强;系统中建立的远程无线微波通讯系统可以实时传输和再现监测信号。

摘要：结合GB 50009—2012《建筑结构荷载规范》中的等效静风荷载计算方法,研究设置主被动可切换的混合调谐质量阻尼器(TMD/ATMD)的规则高层建筑结构的风振分析与实用设计方法。将控制系统的风振控制效果按照风振响应方差相等的原则归结为对受控结构的附加等效阻尼比,推导了控制系统最优参数和附加等效阻尼比的计算公式,给出了惯性质量平均最大行程比、主动控制力和额定功率的简化计算方法;并讨论了主动/被动控制模式的切换准则。最后给出以风振控制Benchmark结构模型为对象的受控结构及混合调谐质量阻尼系统的设计算例。算例分析表明:建议的设计方法可以方便地进行受控结构响应分析和控制系统参数设计;混合调谐质量阻尼器可以有效减小设计等效静风荷载和结构的动力响应。

摘要：采用ANSYS有限元软件建立某大跨度斜拉桥试验室物理模型的三维有限元模型。基于灵敏度分析,选取模型待修正参数和用于模型修正的特征量。采用实验设计方法生成参数样本,通过有限元分析提取对应的特征量信息,进而建立待修正参数与特征量关系的径向基函数响应面模型。通过对响应面模型的拟合误差分析,确定径向基函数的最优形状参数。以斜拉桥自振频率和静态索力构建目标函数。基于建立的响应面模型,采用遗传优化算法进行有限元模型修正。结果表明,采用径向基函数响应面模型拟合斜拉桥设计参数与特征量之间的隐式关系有较高的精度;基于仿真数据的模型修正有较高的精度,基于试验数据的模型修正能得到合理的结果,该方法可有效地修正复杂桥梁结构有限元模型。

摘要：介绍了适合混凝土结构局部压应力、压应变状态监测的嵌入式炭纤维水泥石压敏传感器的概念及其传感原理,并研究了环境温度和湿度两个因素对炭纤维水泥石压敏传感器零点输出的影响;同时从传感器电路设计角度探讨了温度、湿度的补偿方法及其在结构中的应用方式。研究表明:炭纤维水泥石压敏传感器的零点输出对环境温度、湿度的变化比较敏感,温度、湿度的最大影响分别约为6%和200%;对炭纤维水泥石压敏传感器采用“测试-补偿”对耦设置构成的补偿电路可以消除因环境温度、湿度以及极化作用产生的噪声信号对传感器零点输出的影响。

摘要：针对高层结构罕遇地震作用下局部集中损伤破坏易导致整体倒塌的问题,及超静定次数消耗集中且不充分的结构地震失效本质,确定了高层结构耗能构件分批次充分消耗超静定次数的多阶段塑性发展路径,提出了高层结构塑性发展充分、失效方向可控、失效路径延长的渐进地震失效模式。同时,考虑结构多阶段塑性发展过程中地震作用的往复特性、高阶振型影响和非线性内力重分布特点,建立基于多阶段振型组合的标准地震作用,给出了多阶段塑性发展的抗震性能量化需求,建立了基于渐进地震失效模式的高层结构抗罕遇地震设计方法。该方法将高层结构渐进地震失效全过程的复杂设计简化为有限塑性阶段的分段抗罕遇地震设计,解决了高层结构难于抗罕遇地震量化设计的难题。为验证该设计方法的有效性,对一幢10层高层结构进行了抗罕遇地震设计,通过非线性时程分析方法验证了按所提方法设计的结构能够实现结构渐进地震失效模式以及结构抗震性能目标,并对比分析了按所提方法设计的结构与按现行规范方法设计的结构的抗震性能,得到按所提方法设计的结构在地震动峰值加速度为0.22g作用下耗能提高了57%,在非线性静力推覆作用下非线性抗力(基底剪力)最大值提高了15.59%。

摘要：本文首先经过2次等效将土与结构相互作用的多自由度体系等效为单自由度体系,并给出了修正反应谱和等价能力谱的确定方法,进而提出了基于能力谱法考虑土与结构动力相互作用(SSI)效应的结构体系pushover分析方法(SSIPA);然后对3种不同高度考虑SSI效应的结构体系在5条地震动作用下采用本文提出的方法进行了算例分析,将结果与非线性时程分析的结果进行了比较,研究了本方法的适用性和准确性;最后,与建筑抗震设计规范的设计反应谱相结合,对9层考虑SSI效应的钢结构用本文提出的方法进行了弹塑性地震反应分析,根据我国抗震设计规范的规定进行抗震性能的评估验证了本方法的可行性。