钢筋混凝土桥墩加固与修复技术研究

针对钢筋混凝土桥墩常规加固及抗震加固与修复,研究总结了几种国内外传统加固技术及最新加固技术,包括增大截面加固技术、嵌入加固技术、体外预应力加固技术、钢套管加固技术、FRP加固技术、绕丝加固技术及“狗骨式”筋修复纵筋技术等,对不同加固技术的方案原理、材料及适用范围进行了论述比较,不同的加固技术适用于桥墩承载力提高、抗震加固、震后修复等不同的加固需求.     

雅安地区过湿土加固FLAC^3D数值模拟

通过采用石灰加固、水泥加固、水泥加固化剂加固三种加固措施对雅安地区过湿土进行加固,利用FLAC^3D数值模拟软件分别对未加固过湿土,石灰加固,水泥加固,水泥加固化剂加固四种情况进行模拟,并对所得到的Z方向位移云图以及路基表面沉降监测点进行分析表明：三种加固措施达到了加固目的,减少了路堤的沉降量。其中采用水泥加固化剂加固的方案沉降量最小,采用石灰加固措施的方案沉降量最大。案;FLAC^3D;沉降     

某综合办公楼加层加固结构设计方案

以某综合办公楼为例,根据结构加固设计原则,对钢筋混凝土框架结构的加层加固改造设计方案进行了研究,并分析了基础加固、框架柱加固、梁板加固、剪力墙加固等加固方法的特点及具体构造要求,以达到良好的加固效果。     

谈几种建筑结构的加固技术

本文主要阐述了砌体结构加固的直接加固和间接和加固技术、混凝土结构加固的直接加固和一般加固方法,混凝土结构加固改造配套使用技术,如植被技术、托换技术、裂缝修补技术和表层密封技术等,钢结构加固方法,如改变结构计算图形、加大构件截面的加固、直接的加固与固件的连接.     

建筑结构的加固问题分析

本文从我国建筑结构加固的现状入手,阐述了建筑结构加固的必要性,提出了化学灌浆补强法、绕丝加固技术方法、粘钢板加固技术方法、外包钢加固技术方法、预应力加固技术方法、置换混凝土加固技术方法、增大截面积的加固技术方法等七种建筑结构加固的技术方法。重视建筑结构加固技术,延长建筑物的寿命,增加建筑物的使用功能,为构建社会主义和谐社会做贡献。     

传统抗震加固技术和新型抗震加固技术的总结与对比

收集和整理了目前在工程中常见的一些抗震加固技术,按传统抗震加固技术和新型抗震加固技术分别进行介绍.传统的抗震加固技术主要针对混凝土结构和砖混结构,以增大截面法、外包钢加固法、置换混凝土加固法、粘钢加固法和粘碳纤维加固法等为例进行介绍.新型加固技术一般可分为抗震加固、减震加固和隔震加固三大类,每种类型都有不同的加固方法.这些加固方法大都运用了目前较为先进的科学技术,加固效果较为明显,但是造价也相对较高.     

浅谈工程加固

分析了工程加固的意义,介绍了常见的几种加固方法,包括增大截面加固法、粘贴钢板加固法、碳纤维加固法、砌体结构加固法等,以提高人们对工程加固方法的认识,确保工程加固的合理性。     

不同形式加固混凝土梁端部与原混凝土界面抗剪性能试验分析

考虑不同形式加固混凝土梁对加固梁端与原柱混凝土界面的抗剪影响,设计制作了3组9个试验试件进行单调静载试验,主要分析三种不同加固形式(在原梁的单侧、底部和三面围箍加固)对加固梁端部与原柱混凝土界面抗剪性能的影响。试验结果表明:相同加固面积下,三面加固梁优于梁底与梁单侧加固的梁,具有更高的抗剪承载力,加固效果最好。而梁底加固与梁单侧加固承载能力基本相同,但达到极限荷载时梁底加固试件的界面位移值更小,表明梁底加固优于梁一侧加固。同时随着加固面积的增大,同级荷载下纵筋应变越小,应变增长越慢,抗剪能力越强,加固效果越好。     

超载软土地基主动加固控制邻近桩基侧向变形分析

本文以上海某工业厂房为例采用有限元方法讨论了深层搅拌法加固宽度、加固深度等对邻近堆载桩基侧向变位的影响,结果表明:(1)加固存在特征加固深度(临界加固深度和极限加固深度),当加固深度位于临界加固深度和极限加固深度范围内时,可显著降低桩基的侧向变形。当加固深度小于临界加固深度时,不但不能降低邻近桩基的变形,反而会增大桩侧土压力和侧向变形;当加固深度大于极限加固深度后,再增加加固深度效果不明显。加固宽度也有类似现象。(2)加固搅拌桩对邻近堆载桩基侧向位移有三种作用模式,即短桩挤压模式、中长桩遮拦模式和长桩嵌固模式,分别与特征加固深度相对应。(3)在其它条件相同的情况下,提高加固深度比增大加固宽度,能更有效地控制受邻近堆载作用桩基的侧向变形。     

传统抗震加固技术与抗震加固新技术的介绍

我国抗震加固的研究工作始于上世纪60年代,唐山地震后,开始在全国范围内进行建筑结构的抗震加固工作,并进行了大量的试验研究。早期砖混结构以圈梁构造柱和砖墙的钢筋网砂浆面层加固为主。目前,砖混结构则多采用混凝土板墙加固方法,另外碳纤维加固法和高强不锈钢绞线加固法也应用于砖墙的强度加固。混凝土结构的加固方法主要有加大截面加固法、外包钢加固法、转换体系加固法、黏钢加固法和黏碳纤维加固法。本世纪初消能减震技术开始逐渐应用于混凝土框架结构的抗震加固。随着高强不锈钢绞线 高强聚合物砂浆加固技术的研究成熟,越来越多的结构采用该方法进行加固。     

浅议由传统建筑观引发的中西宗教建筑差异

指出中西方传统建筑观有着本质的不同,从而导致中西方宗教建筑在造型、审美、尺度等方面有明显的区别,通过从中西方对建筑的物质性与精神性的不同认识出发,分析了由此引发的中西方宗教建筑的差异。     

玻璃钢锚杆托盘及螺母极限应力和位移分析

为了研究支护用锚杆在极限应力作用下力学特性,建立了锚杆托盘及螺母的有限元模型,采用ANSYS程序对螺母及托盘的应力、位移进行了数值仿真分析。研究了托盘及螺母在极限应力下的接触特征;绘制了托盘及螺母的应力云图,得到了托盘及螺母内部的应力、位移分布情况。结果表明,托盘边缘及托盘内部大小圆盘连接位置较为危险;螺母中间位置由于受托盘的挤压容易发生破坏;加肋可以提高锚杆的极限承载力,为结构的优化提供借鉴。     

堆土加卸载与基坑开挖叠加对既有隧道变形的影响研究

针对堆土加卸载与基坑开挖叠加效应导致既有地铁隧道变形较大的问题,建立考虑加卸载叠加效应影响的三维空间分析模型,研究不同堆土加卸载叠加基坑开挖卸载模式对邻近地铁隧道变形规律的影响,探讨隧道在堆土加载、移土卸载再叠加基坑开挖下的变形规律。结果表明:正上方堆土加卸载对隧道的竖向位移影响较大,是侧向堆土加卸载的3倍～5倍; 在经历堆土加卸载后,隧道会残留不可忽视的变形,其残留竖向位移约为加载后位移的62%; 堆土加卸载叠加侧方基坑开挖时,隧道变形受基坑开挖深度的影响较大,大于隧道埋深的开挖阶段会加剧隧道变形; 4种叠加模式中,正上方堆土加卸载-侧方基坑开挖卸载隧道最终竖向位移最大,约17 mm,侧方堆土加卸载-异侧基坑开挖卸载隧道最终水平位移最大,约8 mm,邻近隧道施工时应充分考虑叠加效应的影响,尽量避免这两种情况。     

Environmental affordances and children’s needs: Insights from child-friendly community streets in China

With rapid urbanization in China, an increasing building density has squeezed the urban public space. Community streets are occupied by motor vehicles or other functions, and can no longer sufficiently support children to carry out safe and independent activities. As an important space for children’s daily natural contact and social activities, the lack of the spatial function of streets results in a decline in children’s subjective initiative and social abilities. The United Nations has stressed the importance of community as the basic unit of space for children’s daily activities in building child friendly cities. It is urgent to reshape child-friendly community streets and support children’s healthy growth. Integrating previous research results on affordance theory and design, children’s growth and environment, and street-game spaces, this study focuses on investigating 23 community streets in four residential communities in Nanjing through questionnaires, interviews, observations, and other methods. Then, from the perspective of cognitive affordance, functional affordance, and social affordance, it analyzes the behavioral possibilities provided by the environment and the needs of the children-user group. Finally, from the perspectives of openness and security, preference and diversity, positive and negative, and reality and potential, it proposes a method to assess the existing environment. This study aims to extract the significant characteristics of the built environment that effectively support and promote children’s outdoors activities, and explore the design strategy of improving street space sharing through optimizing space elements and structure at the medium and micro levels, so as to respond to multiple goals including livable city development from the perspective of child friendliness. This study also tries to change the logical way of design thinking and provide an eco-psychological perspective on how to build a child-friendly community.     

故宫古建筑石勾栏的安装工艺技术

本文以石勾栏为研究对象,阐明了石勾栏的构成与榫卯连接特点,对石勾栏的地栿、望柱、栏板安装工艺做法进行论述,并对石勾栏安装中的灌浆、砌筑以及勾缝所用材料和工艺做法做了调查分析。     

Magnetoelastische Spannkraftmessung in Bauwerken

Magnetoelastic Measurement of Prestressing Force in Civil Structures The knowledge of the tensile force of prestressing steel elements and its reliable and non‐destructive determination are of essential importance for the assessment of the structural health condition of prestressed concrete structures and tie‐back systems in terms of structural safety, serviceability and durability. For the evaluation of the prestressing force in steel tension members, the measurement technique presented in this contribution is using the magneto‐elastic effect (ME‐effect) of ferromagnetic materials. This effect describes the reverse‐proportional correlation between the mechanical stress and the magnetic properties of ferromagnetic materials. The cylindrical coiled sensors pushed over the tendon and the measuring device developed and practically optimized at the iBMB/MPA of the TU Braunschweig enable a fast and reliable measurement of the prestressing steel force after an initial calibration. In this contribution first the state of the art of prestress measurement techniques for steel tension members is presented. Afterwards, the ME‐measuring method with the basics and merits of magneto‐elastic prestressing force identification is shown. Further recent research results as well as several building applications will be discussed.     

Abbeystead Outfall Works: Background to Repairs and Modifications – and Lessons Learned

The explosion at the Abbeystead valve house in May 1984, with its attendant loss of life and injury, forcibly drew the attention of the public to the dangers of methane and other natural gases. It also reaffirmed to the water industry and engineering professions the pervasive nature of the gas and the need to take appropriate measures in the construction, design and operation of any scheme which involves a possible methane presence. The investigations into the source and mechanism of the methane gas ingress, and the design of the permanent repairs and modifications to the scheme, have illustrated many of the risks and problems associated with methane and the measures for dealing with them.
The paper describes the essential repairs and modifications which had to be carried out, the main lessons learned, and the recommendations which are felt to be applicable to new and existing water schemes where methane may be present.     

案例分析在建筑设计教学中的运用

案例分析与解读是模仿在设计教学中的应用和深化。就案例分析与解读的作用、本质以及在设计教学中的应用进行了论述,旨在探讨案例分析在教学运用中的合理模式和正确途径。     

基于点云的钢筋数量和间距自动检查算法

为改进钢筋骨架质量自动检查方法,提出了基于点云的钢筋骨架中钢筋数量和钢筋间距的自动检查算法。该算法在获取钢筋骨架实际点云和设计点云的基础上,首先对这两片点云分别进行降采样,以得到空间密集程度相同的钢筋骨架实际点云和设计点云; 其次,对降采样后的钢筋骨架实际点云和设计点云使用基于主成分分析(PCA)的方法进行粗配准。由于粗配准后的钢筋骨架实际点云和设计点云的配准精度较低,无法直接用于钢筋数量和钢筋间距的检查,对粗配准后的钢筋骨架实际点云和设计点云进行精配准。最后,基于精配准得到的钢筋骨架实际点云和设计点云,依次对钢筋骨架中的钢筋数量和钢筋间距进行检查。结果表明:精配准后的钢筋骨架实际点云和设计点云的配准精度较高,可以用于钢筋数量和钢筋间距的检查; 该算法对钢筋数量检查的准确率为100%,对钢筋间距检查的准确率为80%; 应用该算法可以有效提高复杂钢筋骨架中钢筋数量和钢筋间距检查的效率,降低人工成本。     

Eutrophication: Assessment, Research and Management with Special Reference to Scotland's Freshwaters

In response to the extraordinarily high profile currently maintained by algae, this paper discusses aspects of pure and applied research on eutrophication. In addition to restating a number of issues which were raised decades ago when the importance of this environmental problem was first recognized, the following aspects are explored using data collected mainly over the last 20 years and referring primarily to Scottish studies: (i) algal-nutrient relations and the contrasting manner in which nitrogen and phosphorus enter freshwaters and are sequestered by planktonic organisms; (ii) estimates of the loadings of phosphorus to freshwaters from various sources; (iii) the effects on our perception of algal problems and the use to which the waters are intended; (iv) the extent and limitations of existing scientific knowledge about eutrophication, and its application to the formulation and execution of eutrophication control strategies; and (v) the arguments for maintaining in-depth limnological surveillance programmes.