PVA-ECC受拉構件計算理論及有限元分析
發(fā)布時間：2018-08-31 14:07
【摘要】：聚乙烯醇纖維增韌水泥基復合材料（Polyvinyl alcohol Fiber-Engineered CementitiousComposites簡稱PVA-ECC）是一種拉伸變形性能優(yōu)異的水泥基復合材料，是通過斷裂力學和微觀力學原理對材料體系進行系統(tǒng)設計和優(yōu)化得到的復合材料。PVA-ECC以其高韌性、耐沖切、耐腐蝕等優(yōu)點引起纖維混凝土領域的廣泛關注，國內(nèi)外許多學者和研究人員對PVA-ECC多項力學性能進行了研究，尤其是其抗壓性能和抗拉性能，也取得了一系列豐碩的結果，在自身實驗基礎上，得到了受壓和受拉應力應變曲線。但其結果都是建立在各自實驗環(huán)境、實驗因素的基礎上，給該種材料的廣泛工程設計和工程應用帶來阻礙。PVA-ECC材料的本構關系是進行結構非線性有限元分析和研究其設計理論的基礎。 針對PVA-ECC具有優(yōu)越的拉伸應變硬化特性，本文首先回顧了PVA纖維增強水泥基復合材料的研究進展，并重點講述了PVA-ECC在單軸拉伸性能方面的研究成果，對其單軸拉伸應力-應變曲線進行歸納總結，得到具有代表性的PVA-ECC受拉應力-應變曲線，在此基礎上，對配筋PVA-ECC受拉構件進行力學分析，推導出對應的承載力公式；并采用截面條帶法對PVA-ECC受拉構件進行數(shù)值分析；為了驗證承載力公式的正確性，基于ABAQUS，建立不同偏心距的配筋PVA-ECC受拉構件有限元模型，將有限元結果和理論結果進行對比分析，成果如下： 1、歸納和總結國內(nèi)外關于PVA-ECC軸向拉伸試驗的研究成果，PVA-ECC的單軸拉伸應力-應變曲線可分為單線性應變硬化曲線和雙線性應變硬化曲線，本文采用origin軟件對其進行擬合，表明了單線性應變硬化模型和雙線性應變硬化模型可以很好描述PVA-ECC的單軸拉伸應力-應變曲線。 2、采用PVA-ECC單線型應變硬化模型，通過力學分析方法,對配筋矩形截面的PVA-ECC軸心受拉構件受力全過程進行了分析,以平截面假設為基礎，結合變形協(xié)調(diào)方程和物理方程，經(jīng)過嚴格的數(shù)學推導，得出軸心受拉過程中三個階段的承載力公式。 3、采用同樣的假設，，對配筋矩形截面的PVA-ECC偏心受拉構件受力全過程進行力學分析,經(jīng)過嚴格的數(shù)學推導，得到小偏心受拉構件三個階段的承載力公式和大偏心受拉構件三種破壞形態(tài)的承載力公式。以一具體的配筋PVA-ECC受拉構件為例，作出構件的極限承載力M-N曲線，全面反映了PVA-ECC構件的極限承載力變化狀況。 4、基于截面條帶法對PVA-ECC受拉構件進行數(shù)值分析，得到配筋PVA-ECC受拉構件的M-N曲線，并和理論推導結果進行對比。 5、基于ABAQUS有限元軟件，建立不同偏心距的配筋PVA-ECC受拉構件的有限元模型，將有限元結果和理論推導結果進行對比分析，驗證理論結果的正確性。
[Abstract]:Polyvinyl alcohol fiber toughened cement matrix composite (Polyvinyl alcohol Fiber-Engineered CementitiousComposites) is a kind of cement matrix composite with excellent tensile and deformation properties. PVA-ECC, which is obtained by the systematic design and optimization of the material system through fracture mechanics and micromechanics, has attracted wide attention in the field of fiber reinforced concrete because of its high toughness, punching resistance, corrosion resistance and so on. Many scholars and researchers at home and abroad have studied the mechanical properties of PVA-ECC, especially its compressive and tensile properties, and have obtained a series of fruitful results. On the basis of their own experiments, the stress-strain curves under compression and tension have been obtained. But the results are based on their own experimental environments, experimental factors, The constitutive relation of PVA-ECC material is the foundation of nonlinear finite element analysis of structure and the study of its design theory, which hinders the extensive engineering design and engineering application of this kind of material. In view of the excellent tensile strain hardening properties of PVA-ECC, this paper reviews the research progress of PVA fiber reinforced cement matrix composites, and focuses on the research results of uniaxial tensile properties of PVA-ECC. The stress-strain curve of uniaxial tension is summarized and the representative stress-strain curve of PVA-ECC is obtained. On the basis of this the mechanical analysis of the tensile members of reinforced PVA-ECC is carried out and the corresponding bearing capacity formula is deduced. In order to verify the correctness of bearing capacity formula, the finite element model of PVA-ECC tensile members with different eccentricity is established based on ABAQUS, and the finite element results and theoretical results are compared and analyzed. The results are as follows: 1. The uniaxial stress-strain curves of PVA-ECC can be divided into single linear strain hardening curve and bilinear strain hardening curve. In this paper, origin software is used to fit the strain hardening model. It is shown that the single linear strain hardening model and the bilinear strain hardening model can well describe the uniaxial stress-strain curve of PVA-ECC. 2. PVA-ECC unilinear strain hardening model is used. Based on the assumption of plane section and combined with deformation coordination equation and physical equation, the whole process of PVA-ECC axial tensile members with reinforced rectangular section is analyzed by means of mechanical analysis. The bearing capacity formula of three stages in the process of axial tension is obtained. 3. By using the same assumption, the mechanical analysis of PVA-ECC eccentric tensile members with rectangular section is carried out, and the strict mathematical derivation is given. The bearing capacity formulas of three stages of small eccentricity tensile members and three failure modes of large eccentricity tensile members are obtained. Taking a concrete reinforced PVA-ECC tensile member as an example, the M-N curve of the ultimate bearing capacity of the member is made, which reflects the variation of the ultimate bearing capacity of the PVA-ECC member. 4. Based on the section strip method, the PVA-ECC tensile member is numerically analyzed. The M-N curves of reinforced PVA-ECC tensile members are obtained and compared with the theoretical results. 5. Based on ABAQUS finite element software, the finite element model of reinforced PVA-ECC tensile members with different eccentricity is established. The finite element results are compared with the theoretical results to verify the correctness of the theoretical results.
【學位授予單位】：華南理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TU528
[Abstract]:Polyvinyl alcohol fiber toughened cement matrix composite (Polyvinyl alcohol Fiber-Engineered CementitiousComposites) is a kind of cement matrix composite with excellent tensile and deformation properties. PVA-ECC, which is obtained by the systematic design and optimization of the material system through fracture mechanics and micromechanics, has attracted wide attention in the field of fiber reinforced concrete because of its high toughness, punching resistance, corrosion resistance and so on. Many scholars and researchers at home and abroad have studied the mechanical properties of PVA-ECC, especially its compressive and tensile properties, and have obtained a series of fruitful results. On the basis of their own experiments, the stress-strain curves under compression and tension have been obtained. But the results are based on their own experimental environments, experimental factors, The constitutive relation of PVA-ECC material is the foundation of nonlinear finite element analysis of structure and the study of its design theory, which hinders the extensive engineering design and engineering application of this kind of material. In view of the excellent tensile strain hardening properties of PVA-ECC, this paper reviews the research progress of PVA fiber reinforced cement matrix composites, and focuses on the research results of uniaxial tensile properties of PVA-ECC. The stress-strain curve of uniaxial tension is summarized and the representative stress-strain curve of PVA-ECC is obtained. On the basis of this the mechanical analysis of the tensile members of reinforced PVA-ECC is carried out and the corresponding bearing capacity formula is deduced. In order to verify the correctness of bearing capacity formula, the finite element model of PVA-ECC tensile members with different eccentricity is established based on ABAQUS, and the finite element results and theoretical results are compared and analyzed. The results are as follows: 1. The uniaxial stress-strain curves of PVA-ECC can be divided into single linear strain hardening curve and bilinear strain hardening curve. In this paper, origin software is used to fit the strain hardening model. It is shown that the single linear strain hardening model and the bilinear strain hardening model can well describe the uniaxial stress-strain curve of PVA-ECC. 2. PVA-ECC unilinear strain hardening model is used. Based on the assumption of plane section and combined with deformation coordination equation and physical equation, the whole process of PVA-ECC axial tensile members with reinforced rectangular section is analyzed by means of mechanical analysis. The bearing capacity formula of three stages in the process of axial tension is obtained. 3. By using the same assumption, the mechanical analysis of PVA-ECC eccentric tensile members with rectangular section is carried out, and the strict mathematical derivation is given. The bearing capacity formulas of three stages of small eccentricity tensile members and three failure modes of large eccentricity tensile members are obtained. Taking a concrete reinforced PVA-ECC tensile member as an example, the M-N curve of the ultimate bearing capacity of the member is made, which reflects the variation of the ultimate bearing capacity of the PVA-ECC member. 4. Based on the section strip method, the PVA-ECC tensile member is numerically analyzed. The M-N curves of reinforced PVA-ECC tensile members are obtained and compared with the theoretical results. 5. Based on ABAQUS finite element software, the finite element model of reinforced PVA-ECC tensile members with different eccentricity is established. The finite element results are compared with the theoretical results to verify the correctness of the theoretical results.
【學位授予單位】：華南理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TU528
【參考文獻】
相關期刊論文 前7條
1 郭磊磊;張玉娥;邱曉光;;PVA-ECC材料性能研究及應用[J];河南城建學院學報;2010年01期
2 丁一;陳小兵;李榮;;ECC材料的研究進展與應用[J];建筑結構;2007年S1期
3 徐世p
本文編號：2215227
本文鏈接：http://sikaile.net/guanlilunwen/chengjian/2215227.html
教材專著
