弧型网架的动力特性研究

根据建筑物造型的要求,江苏大学体育馆的屋盖网架设计成了弧形,造型别致,但是对网架的设计,尤其是抗震设计提出了更高的要求。在网架设计相关资料的基础上,对其进行了抗震分析。应用振型分解反应谱法和时程分析法对网架结构分别在小震、大震下的地震反应进行了二阶段设计与验算,分析表明网架满足强度、刚度及抗震设防要求。     

高层建筑顶部塔形网架的设计与抗震分析

本文结合一工程实例，对位于高层建筑顶部的塔形网架的设计与地震反应进行了分析。在按照简化方法［１］进行抗震设计后，应用时程分析法和振型分解反应谱法进行了抗震验算，验证了该简化方法的安全性。讨论了塔形网架的自振特性和抗震性能，并得出了一些有益的结论。     

波浪形网架结构的动力特性研究

天津大学游泳馆屋盖网架,根据其使用功能设计成波浪形,造型独特、新颖,很好地满足了建筑外观的要求。本文在对该波浪形网架进行设计的同时,采用振型分解反应谱法和时程分析法对其进行了竖向及水平地震反应分析,并通过与平板网架的抗震设计方法的比较,对该类波浪形网架的动力特性进行了研究。     

确定楼面反应谱的简化方法

楼面反应谱一般是指楼层质点加速度反应谱,它是对设置在楼面上的设备和管道进行抗震分析的地震输入。为了解决计算楼面反应谱的实用问题,本文提出一种由地面反应谱直接估计楼面反应谱的方法。该方法以建筑结构抗震验算的基底剪力法及相应的放大曲线为基础,具有简单实用的特点。文中最后给出与时程分析途径估计楼面反应谱方法比较的算例,结果表明,对于基底剪力法适用范围内的结构,由简化方法确定的楼面反应谱是可以满足工程要求的。     

非结构构件抗震设计研究

结合非结构构件的分类和抗震设防目标,介绍了非结构构件抗震设计的两种计算方法：等效侧力法和楼面反应谱法,并着重对非法结构构件中隔墙、女儿墙等的抗震设计加以说明,以期指导实际工程中非结构构件的设计。     

建筑抗震支吊架地震作用计算方法评述

准确计算建筑抗震支吊架的地震作用是其抗震设计的基础问题。本文介绍了建筑抗震支吊架的三种地震作用计算方法——等效侧力法、楼面反应谱法和时程分析法的基本原理和应用现状。从计算精度、计算效率和工程实用性等方面详细阐述了三种计算方法的优势和存在的问题,给出了有待进一步研究的课题。     

上海易初摩托厂网架抗震分析

对上海易初摩托厂3．5万m2网架进行了抗震分析，认为对于大型复杂网架抗震计算应采用反应谱法和时程方法进行分析比较．     

斜搁四角锥三层网架的竖向地震响应分析

以振型迭加反应谱法为理论依据,用Fortran 90语言编写了三层网架的竖向地震反应分析程序.对形式新颖的斜搁四角锥三层网架进行了分析.结果表明:这种形式的三层网架杆件受力均匀,具有良好的抗震性能.     

浅析建筑物抗震设计方法

为了更好地从结构抗震原理上认识和理解结构抗震设计方法,分别对静力法、反应谱法、基于反应谱和构造保证延性的设计方法、基于损伤和能量的设计方法、能力设计方法、基于性能/位移的抗震设计方法进行了详细阐述.     

地震反应谱理论在建筑抗震设计中的应用

剖析了目前在建筑抗震设计中广泛采用的地震反应谱法的基本概念及理论方法,并通过与国外抗震规范中设计反应谱的比较,对我国抗震规范中的一些问题进行了讨论。     

预应力锚索抗滑桩结构稳健优化设计

稳健优化设计是稳健设计与最优化技术、计算机技术的结合,当前已成为工程稳健设计研究的一个热点。按照这种方法进行预应力锚索抗滑桩设计,既能在设计阶段保证工程质量的稳健性,又能利用优化设计中众多数学模型和成熟的求解方法,更好地解决多变量、多目标、带约束问题的求解。针对正交设计的不足,用均匀设计代替正交设计,应用专业软件模拟计算不同工况下预应力锚索抗滑桩结构顶部水平位移,通过多元回归分析,用回归模型y(xi)代替函数模型y(xi)作为目标函数,设计参数作为优化变量,规范及合同要求作为约束条件,提出一种预应力锚索抗滑桩结构稳健优化设计方法。以昆洛路K1+440～K1+780边坡为例,阐述用MATLAB语言进行预应力锚索抗滑桩稳健优化设计的方法。     

Buckling analysis design of steel frames

Steel design codes do not provide sufficient information for the efficient design of steel structures against out-of-plane failure, and what is provided is often overly conservative. The method of design by buckling analysis (DBA) specified in one code corrects this situation for beams, but the extension of this method to columns is only referred to, while there is no guidance on how to apply this method to the design of beam-columns and frames.Beam DBA uses the design code formulation for the member nominal design strengths in terms of the section moment capacities and the maximum moments at elastic buckling, accurate predictions of which may be determined by computer programs. Column DBA is similar, in that it uses the design code formulation for the column nominal design strengths in terms of the section compression capacities and accurate predictions of the elastic buckling.However, design codes do not provide formulations for the direct buckling design of beam-columns, but instead use the separate results of beam design and column design in interaction equations. The further extension to frames is not directly possible, because frames are not designed as a whole (except through the rarely used methods of advanced analysis), but as a series of individual members. This paper shows how the method of DBA can be used to design beam-columns and frames as well as beams and columns. Two example frames are designed and very significant economies are demonstrated when the DBA method is used.     

独立基础优化设计及应用

在分析目前常规设计存在的一些缺陷基础上,给出一种独立基础优化设计新方法,有效地解决了现行规范存在的诸如强度和变形影响无法同时考虑等问题。导出了偏心荷载作用下的独立基础底面尺寸设计及独立基础设计的优化数学模型,并编制了求其优化解的复合形法和罚函数法的最优化算法程序及独立基础设计绘图程序。通过算例分析表明,将最优化方法用于基础设计会交大的经济效益。     

A simulation-based method for reliability based design optimization problems with highly nonlinear constraints

Reliability-based design optimization (RBDO) is a topic of interest in the design of economical structures. It allows designers to effectively reach a balanced cost-safety configuration in the design of structures. In this study, a simulation-based method is presented for RBDO problems in which the design variables are treated as random variables. The method works by uniformly distributing samples in the design space and employing a feature that allows the designer to obtain the optimum design solution by performing only one simulation run. Moreover, the proposed feature also helps the designer to use the results of aforementioned run to provide multi-level design solutions when the arrangement of the design problem is changed. The robustness and accuracy of the method are examined by solving design problems with highly nonlinear constraints and comparing with the results of common RBDO methods. The results confirm the robustness of the method for highly nonlinear problems with different design arrangements.     

岩石地下工程锚喷支护设计的人工智能方法及其集成

提出了一种可用于岩石地下工程锚喷支护设计的人工智能综合设计方法。这种方法是首先采用专家系统、人工神经元网络和案例设计3种人工智能方法对同一岩石工程分别进行支护设计，然后再用分区多专家决策算法将所得3种设计结果加以综合，形成最终设计方案，它充分利用了各种人工智能方法的特长，有效地避免了单一方法所容易出现的偏见。应用表叫，人工智能综合设计方法能把工程类比法提高到一个新高度。     

Optimization of structures under stochastic loads

The objective of this study is to develop a method for design under multiple stochastic loads based on optimization. The objective function, such as cost, is minimized under the constraint that the probabilities of various limit states being reached are within allowable limits. The loads are treated as random processes and their combined effects evaluated by the load coincidence method. The limit states considered are either yielding or first plastic hinge at the member level or plastic collapse at the system level. A penalty function approach and a Sequential Unconstrained Minimization method are used. Sensitivity studies with respect to the load parameters are carried out. The dependence of the resultant optimal design on the constraints used, e.g. at the member or system level, is investigated. The proposed approach to the problem is shown to be a viable method and the design using bi-level (member and system) reliability constraints is shown to yield more risk-consistent results.     

Seismic performance of eccentrically braced frame with vertical link using PBPD method

There are special guidelines to design the structures resistant to earthquake forces; parameters such as conditions of the site, seismicity of the site, importance of the structure and the type of the structure are the main effective factors. Consideration of these parameters in calculation and distribution of the earthquake forces are significantly different in various design codes. In most of these design codes, the computation and distribution of earthquake forces are based upon the elastic structural analysis. In this approach, the real behavior of structure is not considered and it may consequently sustain big displacements and irretrievable damages. Therefore, a new design method has been utilized in this paper by which the base shear and its distribution in the height of the structure are calculated according to the plastic behavior of structure and takes advantage of energy balance. The latter is known as performance‐based plastic design method. The study of the behavior of eccentrically braced frames with vertical links while undertaking earthquake loads using performance‐based plastic design method is the main purpose of this study. It is also worthy of notion that the frames are designed using a capacity design method. In addition, the results are compared with those of the International Building Code 2009 method; the results demonstrate that the plastic hinges, the interstory drifts and plastic rotation of links are distributed more uniformly in the height of frames designed by the suggested method compared to International Building Code 2009. Copyright © 2012 John Wiley & Sons, Ltd.     

分布荷载作用下桁架的有效整体设计方法

适当考虑加载区域,对分布荷载作用下桁架的半确定性拓扑及几何学设计的一种有效方法进行介绍。受荷节点不能看作基本节点处理,这些节点的数量和位置作为设计变量来考虑。这些量对桁架及其分布的荷载区域均有影响。在介绍一种新的参数指标的基础上,提出分布荷载作用下桁架的整体设计方法,这一参数可以作为桁架设计中的附加设计目标或约束,它也可以很好地替代半确定性整体设计中的加载域目标。通过一个研究实例验证了该设计方法的有效性。     

门式刚架轻型房屋钢结构防(抗)火设计及计算

介绍了火灾对门式刚架的危害和抗火设计的意义，分析了传统的门刚结构抗火设计方法和基于计算的现代门刚结构抗火设计方法以及存在的问题，对钢结构防火保护和防火涂料的选用进行了评述。