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毕业设计外文资料翻译原文题目：Reinforcement of concrete beamcolumn connections with hybrid FRP sheet 译文题目：具有混合纤维增强塑料片的混凝土梁柱联接部位的加固 院系名称： 工学院建筑系 专业班级： 土木工程2班 学生姓名： 学 号： 指导教师： 附 件： 1.外文资料翻译译文；2.外文原文。附件1：外文资料翻译译文摘要本篇文章描述了对加固后标准尺寸混凝土结构试件进行试验的结果，该试件代表平面框架结构中的梁柱联接部位。设计试验的目的是为了研究在静载条件下纤维增强塑料被应用到梁柱联接部位外表面附近时对所测试件的影响。特别令人感兴趣的是在静载条件下应用纤维增强塑料对增强梁柱联接部位所起的作用。作为研究的关键，为了从外部对混凝土的连接部分进行加固，设计了带有E玻璃无捻粗纱布和碳布的混合纤维增强塑料复合物，并且该复合物结合了短贴原丝毡和带有乙烯基酯树脂的玻璃纤维带。结果显示，对于应用纤维增强塑料改进过的混凝土结构的关键部分能够对混凝土结构的强度和硬度起到增强的作用，同时也能够起到在不同类型荷载条件下增强它们的效果。同时，本篇文章也讨论了为改进和增强混凝土结构的强度和硬度而如何选择纤维增强塑料和结构类型。关键词：混凝土结构；加固；修复；混合纤维增强塑料；绕接技术1.引言为了对混凝土结构进行改进，一个被广泛采用的技术是使用钢外套管放置于现有混凝土柱的周围，这种使混凝土产生侧向限制的技术已经被广泛的研究1，2；而且已经显示重缩载重承载量和混凝土柱的延性增加。然而，这一个技术的缺点是它在实际的应用受到来自腐蚀和固有的缺点。 另一方面，纤维增强塑料日益被采用来加固混凝土，砖石和木结构。通过关键部分的外表面采用纤维增强塑料来加固结构，能够很明显提高结构的载重量和结构的效用。最近几年，纤维增强塑料的材料类型更加的广泛，有玻璃纤维、碳纤维等。它们提供给设计者一个使用的、有效的构造材料，这些材料具有范围很广的模数和强度的特性。和传统的加固技术相比，纤维增强塑料复合物具有特别高的强度和硬度，以及设计上的灵活性、在不利的环境中的可替代性、较强的韧性等优点。通过优化材料组成和结构，使得纤维增强塑料达到最好的加固效果是可能的，同时也是必要的。为了在实际的加固过程中充分利用纤维增强塑料的优点，优化组成材料和结构是非常必要的。研究表明，正方形混凝土柱周围的碳纤维/ 环氧基树脂能够使其负载能力增加8%22%，而这种能力的增强是依赖于大量纤维的使用以及对基层表面的处理。树脂注入技术的使用表明其对绕接效果的改进起了非常重要的作用,研究表明，当使用玻璃无捻粗纱布来增强绕接效果时，不仅能显著提高混凝土的负载能力同时也能够增加混凝土短支柱的变形抵抗能力。此外，通过使用带有环氧树脂的玻璃/ 碳混合增强材料来加固混凝土，当对混凝土柱进行反复的试验来检测它的最初性能时，发现它的负载能力进一步的提高了。根据复合物弯曲的方位和厚度，表明在套箍位置处进行加固会产生更好的效果。尽管已经进行了大量的研究，但是大多数研究中都存在一个不足之处，即他们所做的试验仅限于形状较小较简单的结构，如混凝土圆柱体，而不是真正的结构。此外，有必要根据成本其中包括材料和处理方法来研究使组合结构达到最优化。这就表明，当使用纤维增强塑料来进行基础加固时，应该使用各种材料的优点，不仅仅是带有环氧树脂的碳纤维，同时也应该包括玻璃纤维或带有其它聚合树脂的碳/玻璃纤维的复合物，在这个试验中为了加固一个典型的建筑部分，即梁柱联接部位，设计了一个带有乙烯基酯树脂的碳/E玻璃复合物。为了研究帖有纤维增强塑料对构件的影响，在静载条件下，分别对通过纤维增强塑料加固后的试件和没有加固的试件进行了大量的试验。研究报告是一个合作研究项目的一个组成部分，该项目是有悉尼理工大学、高级材料技术中心和悉尼大学共同合作研究的关于应用高级纤维复合物来增大混凝土的强度和硬度，由此来对混凝土结构进行加固。1、 实验程序为了这一项目设计了三个标准尺寸加固混凝土结构试件，它们代表了典型的梁柱联接部位。图一表示了局部带有纤维增强塑料构件的几何形状。在这三个试件中，其中两个试件相当于混凝土梁柱联接类型（非加固试件），另一个是在梁柱联接部位周围用碳纤维和玻璃纤维复合物加固的试件（加固试件）。这三个试件都使用标准商品混凝土，其强度等级为C40。在图一中也显示了混凝土试件的配筋情况。为了测定混凝土的弹性模量和抗压强度，进行了混凝土抗压试验，该实验是根据AS 10121986标准进行的。图1 试件的几何细节（没按比例确定）2.1 复合式结构三个混凝土结构试件中的一个用复合物进行加固，该复合物由四个部分组成，包括E玻璃无捻粗纱布（WR-600g/ m2）、短贴原丝毡（CSM-300g/m2）、碳布（200g/ m2）和玻璃纤维布（GFT-250g/ m2）详细见表格1和图2，平面详图见图3。双轴平面布置不仅对轴向方向提供了相当的强度，而且对箍部位也起到了同样的作用。而玻璃无捻粗纱布和碳布的使用对于双轴平面布置起到多方位的加固作用，在这个复合式结构中它们都起到了基本的加固作用。把玻璃纤维带应用到箍部位能够提供非常好的限制作用，同时也能够增强结构的完整性。树脂修复系统的选择主要与树脂胶性时间有关。一般来说，当采用湿铺法，可以使用冷环绕树脂系统。对于本次研究所描述的环绕方法没有可采用湿铺机器，所以采用人工方式。在室温下，乙烯基酯树脂和Dastar-R/VERPVE/SW/TP被混合并且混合有1.5%的MEKP，0.4%的CONAP和0.5%的DMA。在室温条件下加工处理树脂。对于玻璃无捻粗纱布/短贴原丝毡层，树脂和纤维的比率是1：1.5，对于碳布比率是1：0.8。混凝土构件被一层lames-wool和一层加固层所包裹。在放置第一层纤维层之前，应使用丙酮来清理混凝土的表面，然后采用树脂涂层去密封混凝土表面上的小洞。然而，当进行进一步的表面处理时，应该有意识的去避免沙粒被暴露在外面。为了确使结构完全加固，每一个复合层都应该用树脂润湿并且卷在混凝土结构之上。表1图2图32.2静载试验设计在水平面上设计混凝土结构试件的静载试验，三个混凝土框架支撑是卷筒状的，如图4。被加载构件末端也是卷筒类型的支撑。然而，其水平运动没有被明显的限制。为了在没个构件末端能够提供理想的卷筒类型边界条件，设计了一个专门的装置，该装置在加载点配有滚筒和一个轴承，如图5。在试验中，使用了4个1000KN的千斤顶。在它们之中唯一一个活动的是那个放在加载构件出的，而其它的几个只简单的起到提供支座反力的作用。图4图52.3仪表使用和数据记录使用4个千斤顶的装载单元放置在每个支撑物和加载点上，测出所家荷载和反作用力的大小。为了获得混凝土框架试件准确的偏差挠曲线。使用12个可变位移传感器，该传感器测量范围为2.5mm到50mm，把它们放在重要位置上来测量挠度偏差。为了使试验更加地规范并对没有经过使用纤维增强塑料加固的混凝土结构试件的变形有更准确的了解，设计了大量应变计来获取所测试试件的压力分布。每一个试件使用56个应变计，其中有28个应变计放置在试件的钢筋处，另外28个30mm的应变计放置在混凝土结构试件的外表面处。按顺序排列应变计以便能够测出连接部分大量的点。对于大部分被测试的连接部分，一个典型的排列方式如图6。应变计在这些部分内部的排列方式如图7。图6图72.4 试验程序程表2给出了所测试试件的名称和一个简单的描述。在正式运行负载进行试验之前，首先对非加固试件进行一系列研究试验，主要是加载40KN，其中一个加到超过50KN。其次，对非加固试件和加固试件不家任何负载，直到达到先前使用负载水平。在每一个试件受到大约100次的加载后，处理所有最终负载试验。表23.结果和分析为了决定纤维增强塑料对加固结构试件的影响，处理了在3个试件上进行的5个试验，其中包括以运行负载进行试验的三个试验和以最终负载进行试验的两个试验。对于每个试验,都进行了四个负载记录，十二个挠度记录和 56 或 64个应变的数据记录。3.1静载试验的确定为了使所做的静载试验得到证实，依次列出了每次试验的静力平衡，如下：外部荷载的平衡：由于在设计这些试验中避免了多余约束的存在，而且把加载装置布置于加载点和反力点，这使得通过使用简单的静力学来检验加载点和反力点的静力平衡变的很方便。表2显示的外部负载平衡令人很满意。断面上力的平衡和力矩的平衡：为了准确地计算内部力和部分力矩，需要在指定的区间内使用应变计。为了处理在一个给定的断面上的标准应变, 做了下列的假设:截面上的应变沿线性变化，换句话说就是在被给定的一个断面上的应变可以用一条应变线表示。在这一假设条件下，采用具有两个解释变量的最小二乘法来获得平面应变，对于每个被给定的区间使用6个平面应变值。图8表示把所测得的平面应变数值与用最小二乘法拟合所计算的数值做了比较。通过计算平面应变可以获得应变值，这些数值将用于随后的计算。对于确定一个被给定的断面内部的平衡，力的计算是通过结合在拉力段和压缩段中所分别测得的数值而完成的。假设混凝土只受压力和受拉区的力主要有钢筋（一些表面带有纤维增强塑料 ）来承担。平衡状态即受压区的合力与受拉区的合力相等。被给定断面上的力矩应该通过这个断面上所受的压力来计算。把它们与通过所测荷载来计算的数值做对比。这些计算的详细公式如附录 A，表3和表 4 表示静载试验的确定。图8表3表43.2负荷凸形竖曲线图9和图10中显示了加固试件的负荷凸形竖曲线和非加固试件的对比情况，其中既包括在使用载荷条件下，又包括在极限载重条件下。结果显示，由于使用了纤维增强塑料，使混凝土的硬度增加了大约45%（使用载荷条件下）。试验表明，在极限载重条件下使用纤维增强塑料加固混凝土结构试件能够使其负载能力提高大约30%。图9图103.3 应变结果的分析由于纤维增强塑料具有加固作用，所以为了估计钢筋处的应变变化，定义了一个参数，即“平面应变约数”。定义如下：在相同的负载条件下，P代表两个非加固试件中最大区间内的平均应变值，R代表两个加固试件中最大区间内的平均应变值。表5和表6对非加固试件和加固试件的最大/最小应变值进行了典型的对比以及在相同荷载条件下不同断面的平均应变约数的对比情况（同见图11）。如果对所有梁部分采用平均应力约数的方法，它将产生 51% 的应变缩减因子。以相同的方式, 对于柱部分将产生55% 的应变缩减因子。平面应变约数可以用以衡量外部使用纤维增强塑料加固的效果。表5表6图113.4 对应用复合物建筑的讨论在使用载荷和极限载重条件下，对混凝土结构试件进行试验，从所得到的结果可以发现，采用纤维增强塑料来加固建筑物，能够成功地提高结构的硬度和负载能力。令人感兴趣的是发现虽然纤维增强塑料的弹性模量仅仅大约是混凝土的一半，但是在增强混凝土的硬度和负载能力方面却扮演非常重要的角色。在应用纤维增强塑料来加固混凝土结构试件之前，虽然没有采取专门的表面处理，但是复合物与混凝土表面之间的连接却没有失败。这可能是由于复合物具有较小的弹性模量。有迹象表明，由于混凝土具有较低抗拉强度，所以弹性模量较小的纤维增强塑料可能对混凝土结构起到更好的加固作用。在采用铺法设计中，厚度的逐渐变化是必要的。这样可以降低在纤维增强塑料中可能产生的应力集中，这些应力集中能够引起混凝土的裂缝。然而，有必要指出，由于仅仅对一些受到限制的试件进行研究，所以这些结论可能有一定的偏差。建议做更多的试验来证明这些结论。4结论作为研究的结果，列出了以下结论：1对加固后标准尺寸混凝土结构试件进行试验已经被成功地处理，所设计的试件代表了平面框架结构中的梁柱联接部位。通过平衡校核证明了由该试验所得出的结论。2. 由无捻粗纱布、碳布、短贴原丝毡和玻璃纤维带组成的复合物有效地证明了纤维增强塑料对混凝土结构试件的加固效果。试验的结果表明由于使用了纤维增强塑料复合物使得混凝土的硬度和负载能力有了明显的提高。结果也表明用较低的成本加强混凝土结构并且使其达到较好的效果，使结构达到最优化是很重要的。3. 静载试验的结果也表明具有较低弹性模量的混合碳/ E玻璃纤维复合物可能会提供更好的连接。然而，这需要被更多的试验证明。4研究也表明应该进行进一步的研究，其中包括加固被破坏的混凝土结构试件，循环荷载和使用不同的结构类型。附录 A假定梁/柱上一个被给定的断面的应变分布是线性的。对于给定的区间，应变能够被表达为公式（A.1）其中a,b,c是常数。考虑两个解释变量的反映模型Yi=0+1xi1+2xi2+ei, (A.2)附件2：外文原文Abstract The paper describes the results of tests on prototype size reinforced concrete frame specimens which were designed to represent the columnbeam connections in plane frames. The tests were devised to investigate the influence of fibre reinforced plastic (FRP) reinforcement applied to external surfaces adjacent to the beamcolumn connection on the behaviour of the test specimens under static loading. Of particular interest under static loading was the influence of FRP reinforcement on the strength and stiffness of beamcolumn connection. As a key to the study, the hybrid FRP composites of E-glass woven roving (WR) and plain carbon cloth, combined with chopped strand mat (CSM), glass fiber tape (GFT) with a vinyl-ester resin were designed to externally reinforce the joint of the concrete frame. The results show that retrofitting critical sections of concrete frames with FRP reinforcement can provide signification strengthening and stiffening to concrete frames and improve their behaviour under different types of loading. The selections of types of FRP and the architecture of composites in order to improve the bonding and strength of the retro-fitting were also discussed. Author Keywords: Concrete structure; Strengthening; Rehabilitation; Hybrid FRP composite; Wrapping technique 1. IntroductionA widely adopted technique for retrofitting concrete structure is to use steel jackets placed around existing concrete columns 1 and 2. The use of steel encasement to provide lateral confinement to the concrete in compression has been studied extensively 3 and 4, and has shown increase in the compression load carrying capacity and ductility of the concrete columns. However, the shortcomings of this technique are that it suffers from corrosions as well as inherent difficulties during practical applications. Fibre reinforced plastic (FRP), on the other hand, is increasingly being used to reinforce concrete, masonry and timber structures. The load carrying capacity and serviceability of existing structures can be significantly augmented through externally retrofitting critical sections with FRP sheeting. In recent years FRP materials with wide range of fibre types of glass, aramid or carbon provide designers with an adaptable and cost-effective construction material with a large range of modulus and strength characteristics. Comparing with traditional rehabilitation techniques, the FRP composites have high specific strength/stiffness, flexibility in design and replacement as well as robustness in unfriendly environments. With FRP composites it is possible and also necessary to achieve the best strengthening results by optimising the constitute materials and architecture. Optimisation of the constitute materials and architecture becomes essential in order to utilise the superiority of FRP composites in application of rehabilitation 5, 6, 7, 8 and 9. It was found that winding of carbon fiber/epoxy composites around square concrete columns can increase the load carrying capacity by 822%, depending on the amount of fibres used and treatments of substrate surface 10. The use of resin infusion technique was shown to contribute to substantial improvements in composite wrapping efficiency, and the use of woven glass roving, as the reinforcement in composites wrapping, was found to significantly increase both load carrying capacity and deformation resistance capacity of the concrete stubs 2. Furthermore, through the use of glass/carbon hybrid reinforcements with an epoxy resin, replication of initial performance of concrete stubs subjected to deterioration was shown possible, with a simultaneous further improvement in load carrying capacity. In terms of the effects of orientation and thickness of the composites warps, it was found that the predominant use of reinforcements in the hoop direction would result in high efficiency 11. Despite the large number of research carried out, one shortcoming of most studies has been that they were limited to simple small size components, such as concrete cylinders, rather than real structures. Furthermore, it is essential to study the optimisation of composites architectures in terms of cost effectiveness including materials and processing methods. This implies that the reinforcement of infrastructure with FRP composites should utilise the advantages of various materials, not only carbon fibers with epoxy resin, but also glass fiber or hybrid of carbon/glass fibres with other polymer resins. In this experimental investigation, a hybrid of carbon/E-glass with vinyl-ester resin composites jacket was designed to reinforce a typical building components, namely a columnbeam connection. Static tests were then conducted on FRP reinforced and non-reinforced specimens with extensive instrumentation to study the influence of the designed composite reinforcement. The investigation reported in the paper forms part of a collaborative research program between the University of Technology, Sydney and the Centre for Advanced Materials Technology, the University of Sydney in relation to application of advanced fibre composites to strengthen, stiffen and hence rehabilitate concrete structures. 2. Experimental proceduresThree prototype size reinforced concrete frame specimens, representing typical concrete columnbeam connection, were designed for this study. Geometry of the specimens with location of FRP composite reinforcement is illustrated in Fig. 1. Among three specimens, two of them are as-is concrete beamcolumn connection type (none composites-reinforced (Non-CR) specimens) and one specimen was reinforced by the hybrid of carbon fiber and glass fibre composites around the columnbeam joint (composites-reinforced (CR) specimen). All three specimens were pre-cast using standard commercial mix grade 40 concrete. The steel reinforcement of the concrete specimens are also shown in Fig. 1. Concrete compression tests based on the Australian Standard (AS 10121986) were conducted on the samples taken during the concrete pour in order to determine the modulus of elasticity and ultimate compression strength (UCS) of the concrete.2.1. Composites architectureOne of the three concrete frame specimens was reinforced with hybrid composites. The hybrid composites consists of four basic architectures, namely E-glass woven roving (WR/600 g/m2), chopped strand mat (CSM-300 g/m2), carbon cloth (plain weave-200 g/m2) and glass fibre tape (GFT-250 g/mm2). The details of the composites architecture are shown in Table 1 and Fig. 2. Details of lay-up are illustrated in Fig. 3. WR and carbon cloth are a multi-directional reinforcement with biaxial plain weaving which provide equivalent strength in both axial and hoop directions. They play the basic reinforcement role in this composites architecture. GFT applying at hoop direction provides very good confinement and enhances structural integrity. The selection of resin curing systems is mainly concerned with the resin gel-time at ambient temperature, which is critical to wrapping process. In general, cold setting resin systems (ambient temperature curing) can be used when wet lay-up process is applied. Since no lay-up machine is available for the wrapping process described in this study, the hand lay-up method was used. The vinyl-ester resin, Dastar-R/VERPVE/SW/TP, was mixed with 1.5% of MEKP (methyl-ethyl-ketone-peroxide), 0.4% of CoNap (Cobalt napthenate), and 0.5% of DMA (Dimethylaniline) at ambient temperature. The resin cures at ambient temperature. The weight ratio between resin and fibre layers was 1:1.5 for WR/CSM layers and 1:0.8 for carbon cloth, respectively. The concrete frame was wrapped by a lames-wool roller and a consolidating roller. Before laying the first fibre layer, the concrete surfaces were cleaned up using acetone, and a thin resin coat was applied to seal micro holes on the surface of concrete columns. However, further surface treatment such as sanding surface to expose the aggregates was intentionally avoided. Each composite layer was wetted with the resin and rolled onto the concrete frame to ensure full consolidation. Table 1. Details of five composite systems with a composite architectures2.2. Design of static testsThe static tests of the concrete frame specimens were setup in a horizontal plane. The three supports of the concrete frame (no load applied) were roller type as shown in Fig. 4. The end at which load was applied was also a roller type support, however, horizontal movements were obviously not prevented. In order to provide the ideal roller type boundary conditions at each end as designed, a special setup was developed with combination of rollers and a swivel head at each supporting/loading point (Fig. 5). Four 1000-kN-hydraulic jacks were used in the tests. Among them, the only active jack was the jack that applied loads, while others were simply acting as adjustable packing to providing the reactions. Fig. 4. Illustrative sketch of test set-up for static test.Fig. 5. Set-up for static test of concrete frame.2.3. Instrumentation and data loggingApplied load as well as reaction forces were measured using four 998.8 kN load cells located in each of four supporting/loading positions. In order to obtain detailed flexural deflection curves for the concrete frame specimens, twelve linear variable displacement transducers (LVDTs) with a range from 2.5 to 50 mm were used at strategic locations to measure the flexural deflections. Extensive strain gauging was designed to capture the stress distribution of the testing specimens in order to validate tests and gain an insight into the behaviour of the concrete frame with or without FRP reinforcement. The total number of strain gauges was 56 for each specimen, in which 28 strain gauges (5 mm) were located on steel rebars and the rest (30 mm strain gauges) were located on the external surface of the concrete frame specimens. Locations of the strain gauges were arranged so that the strains on various points of the cross sections could be captured. A typical strain gauge arrangement for most measured cross sections is shown in Fig. 6. Locations of strain gauges inside the section are shown in Fig. 7. Fig. 6. Location of cross sections of the concrete frame for strain gauging.2.4. Test procedureDesignations of test specimens and a brief description are given in Table 2. Prior to being formally tested at service load level, the first non-CR specimen was subjected to a series of investigative tests mostly loaded at the service load level of 40 kN with one single overload up to 50 kN. The second non-CR specimen and the CR specimens were not subjected to any loading until the initial service load level tests. All ultimate load tests were conducted after every specimen was exposed to about 100 cycles of cyclic loading at service load levels.Table 2. Applied load and reactions for typical tests (unit: kN)3. Results and analysisIn order to determine the influence of FRP composites, five sets of tests were conducted on the three specimens including three tests at service load levels and two at the ultimate load level. For every test, logged data consisted of four load records, twelve deflection records and 56 or 64 strain records. 3.1. Validation of the static testsTo validate the performed tests, the static equilibrium for each test was verified as follows: Equilibrium of external loads: As redundancy was avoided in design of these tests and load cells were placed at each loading or reaction point, it was convenient to check equilibrium of the load/reaction forces through simple statics. Table 2 shows that the equilibrium of external loads was satisfied. Equilibrium of forces and equilibrium of moment on cross sections: In order to calculate the internal forces and sectional moments, strains on the designated sections were required. To process the measured strains on a given cross section, the following assumption was made: the strains vary linearly through the cross sections. In other words the strains at a given cross section can be represented by a strain plane. Under this assumption, least square method with the two explanatory variables was adopted to obtain the strain plane for