環(huán)向預應(yīng)力FRP加固混凝土圓柱的主動約束機理研究
發(fā)布時間：2018-07-26 14:49
【摘要】：摘要：隨著各種工程結(jié)構(gòu)加固改造技術(shù)的不斷發(fā)展,研究人員需要更加精確地評估各種加固技術(shù)的作用效果,并建立具有針對性的計算模型。加固混凝土圓柱是工程結(jié)構(gòu)加固改造技術(shù)的主要問題之一。由于傳統(tǒng)的FRP加固混凝土圓柱技術(shù)存在應(yīng)力滯后問題,而環(huán)向預應(yīng)力FRP加固混凝土圓柱能夠?qū)诵幕炷潦艿街鲃蛹s束,充分發(fā)揮FRP材料的高強性能,避免FRP的應(yīng)力滯后,從而起到更好的加固效果。故本文進行了環(huán)向預應(yīng)力FRP主動約束混凝土圓柱的試驗研究、主動約束機理及損傷演化規(guī)律研究,建立針對環(huán)向預應(yīng)力FRP主動約束情況下混凝土圓柱的損傷模型并提出預應(yīng)力度的建議值,以指導實際工程。 (1)在細觀層次上,受壓混凝土破壞主要由于混凝土中的骨料與水泥砂漿的泊松比不同,通過變形協(xié)調(diào)導致混凝土產(chǎn)生損傷。 (2)環(huán)向預應(yīng)力FRP加固混凝土圓柱的軸心受壓試驗完成了包括對比柱在內(nèi)的18個試件,研究了預應(yīng)力大小、混凝土強度等級、截面尺寸和表面處理情況等四個影響因素；使用有限元軟件進行數(shù)值模擬,分析了主動約束混凝土圓柱的應(yīng)變演化規(guī)律,提出預應(yīng)力度的建議值為0.2。 (3)從構(gòu)件層次提出了環(huán)向預應(yīng)力FRP主動約束混凝土圓柱的損傷演化規(guī)律。 (4)將損傷變量視為內(nèi)變量,基于等效應(yīng)變原理,提出了一個含損傷內(nèi)變量的構(gòu)件層次的環(huán)向預應(yīng)力FRP主動約束混凝土圓柱的本構(gòu)模型,計算值與試驗值吻合較好。 (5)證明了高約束比下,環(huán)向預應(yīng)力FRP主動約束混凝土圓柱可不考慮尺寸效應(yīng)的影響。 (6)證明了對圓柱表面的FRP涂覆浸漬膠增加了試件的承載力和延性性能；對圓柱表面的混凝土打磨處理對試件的靜力性能無明顯影響。
[Abstract]:Absrtact: with the continuous development of various reinforcement and reconstruction technologies of engineering structures, researchers need to evaluate the effect of various reinforcement techniques more accurately and establish a targeted calculation model. Strengthening concrete columns is one of the main problems in strengthening and reforming engineering structures. Because of the problem of stress lag in the traditional FRP technique for strengthening concrete columns, the RC columns strengthened by circumferential prestressed FRP can be actively confined to the core concrete, which can give full play to the high strength performance of FRP materials and avoid the stress lag of FRP. In order to play a better reinforcement effect. In this paper, the experimental study, the mechanism of active restraint and the law of damage evolution of concrete columns with circumferential prestressed FRP are carried out. The damage model of concrete cylinder under the active restraint of circumferential prestressed FRP is established and the suggested value of prestress degree is put forward to guide the practical engineering. (1) at the mesoscopic level, The failure of compressive concrete is mainly due to the difference of Poisson's ratio between aggregate and cement mortar. Concrete damage is caused by deformation coordination. (2) the axial compression test of concrete columns strengthened by circumferential prestressed FRP has completed 18 specimens, including contrast columns, and studied the size of prestress and the grade of concrete strength. In this paper, the strain evolution law of concrete columns with active confinement is analyzed by using finite element software to simulate the four influencing factors, such as section size and surface treatment. The suggested value of prestress is 0.2. (3) the damage evolution law of RC columns with circumferential prestressed FRP active confinement is proposed from the member level. (4) the damage variable is regarded as an internal variable based on the equivalent strain principle. In this paper, a constitutive model of RC columns with annular prestressed FRP active confinement with internal damage variables is proposed. The calculated values are in good agreement with the experimental values. (5) it is proved that under the high constraint ratio, the constitutive model can be obtained. The effect of size effect can be ignored in the circumferential prestressed FRP active confined concrete cylinder. (6) it is proved that the FRP coating impregnating adhesive on the cylindrical surface increases the bearing capacity and ductility of the specimen; The static properties of the specimens are not affected by the grinding treatment of concrete on the cylindrical surface.
【學位授予單位】：北京交通大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：TU375.3
本文編號：2146359
[Abstract]:Absrtact: with the continuous development of various reinforcement and reconstruction technologies of engineering structures, researchers need to evaluate the effect of various reinforcement techniques more accurately and establish a targeted calculation model. Strengthening concrete columns is one of the main problems in strengthening and reforming engineering structures. Because of the problem of stress lag in the traditional FRP technique for strengthening concrete columns, the RC columns strengthened by circumferential prestressed FRP can be actively confined to the core concrete, which can give full play to the high strength performance of FRP materials and avoid the stress lag of FRP. In order to play a better reinforcement effect. In this paper, the experimental study, the mechanism of active restraint and the law of damage evolution of concrete columns with circumferential prestressed FRP are carried out. The damage model of concrete cylinder under the active restraint of circumferential prestressed FRP is established and the suggested value of prestress degree is put forward to guide the practical engineering. (1) at the mesoscopic level, The failure of compressive concrete is mainly due to the difference of Poisson's ratio between aggregate and cement mortar. Concrete damage is caused by deformation coordination. (2) the axial compression test of concrete columns strengthened by circumferential prestressed FRP has completed 18 specimens, including contrast columns, and studied the size of prestress and the grade of concrete strength. In this paper, the strain evolution law of concrete columns with active confinement is analyzed by using finite element software to simulate the four influencing factors, such as section size and surface treatment. The suggested value of prestress is 0.2. (3) the damage evolution law of RC columns with circumferential prestressed FRP active confinement is proposed from the member level. (4) the damage variable is regarded as an internal variable based on the equivalent strain principle. In this paper, a constitutive model of RC columns with annular prestressed FRP active confinement with internal damage variables is proposed. The calculated values are in good agreement with the experimental values. (5) it is proved that under the high constraint ratio, the constitutive model can be obtained. The effect of size effect can be ignored in the circumferential prestressed FRP active confined concrete cylinder. (6) it is proved that the FRP coating impregnating adhesive on the cylindrical surface increases the bearing capacity and ductility of the specimen; The static properties of the specimens are not affected by the grinding treatment of concrete on the cylindrical surface.
【學位授予單位】：北京交通大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：TU375.3
【參考文獻】
相關(guān)期刊論文 前10條
1 袁泉,姚謙峰,賈英杰;密肋復合墻板的恢復力模型與損傷模型研究[J];四川建筑科學研究;2004年04期
2 王向東,徐道遠,朱為玄;混凝土結(jié)構(gòu)的損傷模型及損傷場分析[J];北方交通大學學報;2003年01期
3 陳波;李付國;何敏;;延性金屬材料損傷變量的實驗表征方法研究[J];稀有金屬材料與工程;2011年11期
4 陳升平,余天慶,劉祖德;混凝土宏觀損傷與細觀損傷的結(jié)合[J];大連理工大學學報;1997年S1期
5 熊輝霞;司馬玉洲;張耀庭;;基于損傷理論的預應(yīng)力混凝土梁彈性模量分析[J];工程力學;2010年S2期
6 秦嶺,劉彥青,楊慶生;FRP/RC預應(yīng)力雜交柱在軸向荷載作用下的應(yīng)力-應(yīng)變關(guān)系分析[J];工業(yè)建筑;2002年11期
7 邱玲,徐道遠,朱為玄,鄧愛民;混凝土壓縮時初始損傷及損傷演變的試驗研究[J];合肥工業(yè)大學學報(自然科學版);2001年06期
8 張衡;魏德敏;;混凝土多軸彈塑性損傷本構(gòu)模型[J];混凝土;2009年05期
9 劉紅義;張勁泉;程壽山;和海芳;;混凝土芯樣抗壓強度尺寸效應(yīng)研究[J];混凝土;2012年02期
10 李忠友;紀秋林;鄧勇;劉元雪;;巖土材料損傷演化規(guī)律研究[J];后勤工程學院學報;2009年01期
相關(guān)博士學位論文 前2條
1 吳寒亮;芳綸纖維布約束混凝土短柱的尺寸效應(yīng)研究與多尺度分析[D];北京交通大學;2010年
2 田威;混凝土損傷演化的CT研究及其在細觀數(shù)值模擬中的應(yīng)用[D];西安理工大學;2009年
相關(guān)碩士學位論文 前1條
1 白曉彬;環(huán)向預應(yīng)力FRP加固混凝土圓柱軸心受壓性能研究[D];北京交通大學;2011年
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