基于振型损伤的高层建筑结构地震破坏准则

针对高层建筑结构在地震作用下的地震损伤现象,参考国内外房屋建筑结构的损伤分析模型,本文以地震作用下高层建筑结构各阶振型对应的损伤指数为基础,建立了新的高层建筑结构地震破坏准则,通过这些准则计算分析了国内21幢高层建筑结构模拟地震振动台试验模型,并结合振动台试验结果划定了按这些准则进行计算时各种结构破坏状态对应的破损指数范围。探讨了在基于性能的抗震设计中如何应用这些准则的原理与方法,并以日美联合足尺实验模型为例作了说明与论证。     

含裂隙类岩石材料的局部化渐进破损模型研究

结合含裂隙类岩石材料模型试验观测结果，从含裂隙类岩石材料破坏过程和破坏机制出发，将表征体单元（RVE）划分为弹性区及剪切局部化带两个部分，并把剪切局部化带内的变形过程抽象为胶结强度弱化及摩擦强度增强两个阶段。重点考虑了这两个阶段一前一后发挥作用这一由试验所揭示的结构性破坏本质，同时借助于试样的滑移变形定义与胶结强度弱化相关的破损变量，抓住试样渐进性破坏的特征，进而采用细观链式模型及均匀化方法将破坏过程的细观特征与宏观力学特性相结合，建立含裂隙类岩石材料局部化渐进破损模型的理论公式。最后对已建立的含裂隙类岩石材料局部化渐进破损模型进行试验验证，模型计算结果与M．Yumlu和M．U．Ozbay的试验结果吻合很好，证明所提出模型的正确性。     

结构性粘土的弹塑性损伤模型

本文从损伤力学观点出发,建议了一个可以考虑粘土结构破损过程的损伤力学模型,推导了弹塑性损伤矩阵,并制定了相应的计算方法和编制了比奥固结理论的有限元计算程序。模型的计算参数共有9个,可以方便地通过原状土的有侧限和无侧限压缩试验测定。文中从湛江粘土的试验资料出发整理了计算参数,并就10m厚粘土地基上承受均布条形荷载的算例进行了计算,结果定性地与国内外原观资料一致。     

建筑结构学报1988年(第9卷第1-6期)目录

赎筑结构的理论研究焊接工形柱承载能力的试验及理论研究钢纤维受弯构件荷载一变形全过程分析新型横配筋砖砌体试验研究采用现场非破损试验方法对砖砌体力学 性能的侧定研究和分析钢筋硷构件的收缩应力与翘曲预应力超静定结构的等效荷载计算预应力硷受扭构件的抗裂度及强度计算网状球壳的连续化分析方法广义位移的有限条法及其在高层建筑结 构分析中的应用井式梁的最大挠度系数夹板墙的试验研究与加固设计钢压弯构件弯扭屈曲的研究网格圆柱扁壳的稳定性硷受拉应力一变形全曲线的试验研究自立式高耸结构抗风可靠性分析的 改进方法加权残值法…     

高层建筑框支剪力墙结构的空间分析

本文利用广义连续化方法与矩阵位移法联合求解,对高层建筑框支剪力墙结构进行空间分析。本文舍弃了底部框架顶层柱顶转角相等这一通常的假设,同时,考虑了上部剪力墙与底部框架交接区附近的楼板变形。理论计算与试验结果符合较好。     

排水管道结构性修复用内支架有限元计算及试验研究

现有的排水管道非开挖修复技术并不能解决破损管道结构承载能力下降的问题。为解决此问题,本文主要研究了一种用于排水管道结构性修复的管道内支架,该型内支架采用开合管片的设计,使其与原管道结构共同受力。通过拼装结构设计,简化修复工艺。经有限元计算及荷载试验验证,该型管道内支架能有效增强破损管道的承载能力,为需要结构补强的管道修复提供参考依据。     

铁路隧道衬砌极限状态法设计验证研究

为了验证极限状态法在隧道衬砌设计中的可操作性,分别采用极限状态法和破损阶段法对铁路隧道衬砌进行了试设计,并对比分析了两种方法的试设计结果。研究结果表明:(1)当衬砌为素混凝土结构时,极限状态法的计算厚度均比破损阶段法计算厚度大,最大相差20 cm,需对极限状态法抗裂验算公式中的调整系数γ_d重新校核,校核后γ_d=1.55;(2)针对钢筋混凝土衬砌结构及明洞结构,极限状态法的设计结果与破损阶段法设计结果基本相同,钢筋混凝土结构的极限状态方程中相关分项系数及调整系数取值是合理的。(3)采用极限状态法(γ_d=1.55)与破损阶段法试设计工程投资相当,极限状态法较破损阶段法工程投资增加237万元,增加1%。     

破损大型屋面板受弯承载力试验研究

破损构件承载力计算是钢筋混凝土结构耐久性评估的关键问题。对6块从工业厂房中拆卸的大型屋面板进行试验研究,试验和理论分析结果表明,构件破损程度对板的承载力有明显影响,锈蚀钢筋的力学性能退化及由此引起的钢筋和混凝土之间粘结性能的退化是承载力下降的内在原因。立足于现行规范的承载力计算公式,提出了破损屋面板受弯承载力计算模型。     

FWD及在嘉浏高速公路中的应用

路面结构状况的评价方法可分为破损评价和非破损（NDT）评价两种。破损评价方法是路面结构性能评估最直接的方法,它直接在路面上钻芯取样,然后在实验室进行试验,其结果通过与设计标准相比较来估算、判定路面各层结构层的承载力。但这种方法不仅费时费力,而且在野外取样过程中芯样必然产生扰动,使室内试验结果与原位材料的性质产生偏差。非破损评价方法则是通过路面无损检测设备（目前国际上采用的较先进的设备是FWD,即锤式弯沉仪）测量路面弯沉、反映路面结构的强度。由于FWD可较好地模拟行车荷载的作用,并可快速、准确地采集路面弯沉盆和路面动态反应信息。这种方法与其它静态检测技术相比具有明显优势,因而愈来愈受到公路研究人员的重视。     

基于神经网络的框架结构破损评估

提出了基于神经网络的框架结构破损评估方法，为动力条件下结构的破损评估提供了一条新的途径。通过计算模拟，对本方法的适用性和有效性进行了讨论，数值结果证实了该方法的可行性。     

The effect of the infill in arched structures: Analytical and numerical modelling

Although arches, vaults and domes were essential structural elements in ancient engineering works, their structural analysis presents a challenge to modern designers. It was well known by the medieval builders that infill is essential for the stability of arched structures. Nevertheless, some disasters occur nowadays due to incorrect infill removal, usually done with the purpose of decreasing the applied load. In the present work a comprehensive analysis of the infill influence on the structural behaviour of arched structures is performed. For this purpose analytical models based on equilibrium considerations and finite elements models are used. Experimental results obtained from the Bargower bridge destructive test, are used to calibrate the numerical results. Some conclusions regarding the structural behaviour of arched structures and modelling strategies are presented.     

块状结构岩体在一般水压分布模式下的不连续变形分析

提出了三维不连续变形分析方法中地下水压力的模拟方法。并通过钻孔水位观测数据插值拟合地下水位面,建立了作用在任意形状块体单元表面上的一般水压分布模式,利用最小势能原理推导了水压力荷载对三维不连续变形分析方法总刚矩阵的贡献。地下水对滑坡稳定性影响的算例分析表明该方法是有效的。     

Findings of the International Road Tunnel Fire Detection Research Project

Fire detection systems are essential fire protection elements for road tunnels to detect fires, activate safety systems and direct evacuation and firefighting. However, information on the performance of these systems is limited and guidelines for application of tunnel fire detection systems are not fully developed. The National Research Council of Canada and the Fire Protection Research Foundation, with support of government organizations, industries and private sector organizations, have completed a research project to investigate current fire detection technologies for road tunnel protection. The project included studies on the detection performance of current fire detection technologies with both laboratory and field fire tests combined with computer modelling studies. This paper provides an overview of the findings of the project. Fire detectors, fire scenarios and test protocols used in the test program are described. A summary of the research results of the series of full-scale fire tests conducted in a laboratory tunnel facility and in an operating road tunnel as well as of the computer modelling activities will be reported.     

Non-destructive testing of rock bolts using guided ultrasonic waves

The research outlined in this paper is aimed at the development of a portable non-destructive testing instrument for evaluating the condition of rock bolts. In applications such as coal mine roof reinforcement, the opportunities for rock bolt inspection are currently limited to destructive techniques such as the pull-out test. It is proposed that guided ultrasonic waves can be used to solve this inspection problem, using a pulse-echo test carried out from the free end of the bolt. Suitable test frequencies have been identified through the use of modelling software, and successful laboratory and site trials have been undertaken. The research has shown that the proposed approach is capable of determining the bolt length, and of identifying major defects such as necking, deformation, and loss of resin encapsulation.     

Applicability of computer simulation to solving of waste and wastewater management,and pollution prevention problems

Concepts and methodologies of model building, modelling and computer simulation are presented. First, analysis of model types, classification and modelling philosophy are outlined. Next, special emphasis is given to the conceptual and technical tools applied in computer simulation. Finally, some examples of computer simulation application to solving of environmental problems are discussed.     

用墙板单元分析框架剪力墙结构

本文分析比较了目前国内外计算框架剪力墙结构的常用方法,根据剪力墙变形的主要特点,采用一种墙板单元分析方法,即将墙用墙柱代替,上下端设刚域,并与框架梁柱节点铰接。本文对文献[1]的公式推导作了一些校正,导出墙板单元的刚度矩阵,编制出电算程序。用本程序分析框剪结构具有输入数据方便、计算量小、精度高以及直接给出剪力墙各分肢内力的特点。且能将剪力墙组台到框架中的任意位置上,能进行纯框架或纯剪力墙结构的分析,具有应用范围广、经济实用的优点。     

钢筋混凝土楼梯变形试验研究及设计建议

在分析有关文献资料的基础上，考虑各种不同因素的影响，对试件进行了优化设计，初步探讨了钢筋混凝土楼梯梯段的破坏和变形特征，提出考虑踏步作用的楼梯梯段挠度计算方法。对比试验结果表明，本文建议的设计方法不仅能更好地反映楼梯踏步的作用，计算结果更符合梯段的实测变形，而且方法简便，可为实际工程设计提供参考。     

Seismic assessment of rc buildings by estimation of effective parameters on seismic behaviour using non‐destructive tests

Seismic assessment of existing buildings is needed in many cases: change in construction usage (change in applied loads), undesirable construction quality, disparity between standard specimen and technical specification of design, absence of construction plans and modification of codes. Seismic assessment is the first step towards rehabilitation of constructions or other schemes to decrease damages and personal injuries. In this regard, engineers should be able to precisely estimate effective parameters on seismic behaviour, to utilize them in mathematical modelling of structures for increasing their reliability. This aim can be achieved by destructive or non‐destructive tests (NDT). In this paper, NDTs for estimating static and dynamic characteristics of reinforced concrete structures are reviewed. Finally, two essential dynamic NDTs, forced vibration method and ambient vibration method, are discussed in detail, and are proposed for seismic assessment in all kinds of structures. Copyright © 2009 John Wiley & Sons, Ltd.     

Some comments on the numerical analysis of plates and thin-walled structures

The paper briefly reviews the theoretical analysis of plates structures that might exhibit multiple ‘loading paths’ and highlights the need for engineers using non-linear numerical modelling to be aware of the multi-mode phenomenon and to ensure that the modelling is set up in such a manner that the various ‘loading paths’ and possible changes of path would be incorporated in the modelling response. The paper presents a simple example of numerical analysis of thin-plate buckling that involves ‘coupled buckling modes’ and provides comments on suitable methods for defining in a simple and straightforward way the numerical modelling that could ensure that results from computer analysis describe the physically correct relationship between applied loadings and deformations of thin-walled structural components.     

冷弯薄壁卷边槽钢偏心受压构件承载力计算的折减强度法

为了研究冷弯薄壁卷边槽钢偏心受压构件的极限承载力,对13根偏心受压的冷弯薄壁卷边槽钢进行了破坏性试验,并建立有限元分析方法对试件进行模拟分析,有限元分析结果与试验结果吻合良好,验证了有限元方法的有效性;对典型截面构件进行大量的参数分析,研究截面尺寸、长细比、荷载作用点位置及材料特性等因素对卷边槽钢偏心受压构件极限承载力...