本文選題：瀝青混合料 + 修正Burgers蠕變模型��； 參考：《西安建筑科技大學》2015年碩士論文

【摘要】：瀝青路面以其良好的性能在道路建設中得到廣泛的應用,雖然它有很多的優(yōu)點,但是在路面的施工階段,投入使用階段以及維護過程中都會產(chǎn)生不同程度的損傷,隨著這些損傷的不斷累積,路面結(jié)構(gòu)內(nèi)部的裂化程度越來越嚴重,從而導致路面結(jié)構(gòu)的承載力減小,加速路面結(jié)構(gòu)破壞,減少其剩余使用壽命,在一定程度上為國家造成了損失,所以很有必要搞清楚損傷的演化過程以及損傷對其內(nèi)力和變形產(chǎn)生的影響。本文在粘彈性理論和損傷力學的基礎上,推導出了瀝青混合料的蠕變損傷本構(gòu)模型,并采用有限元軟件ABAQUS建立三維模型,研究其在考慮損傷和無損傷兩種狀態(tài)下力學響應的變化。在此過程中,主要解決的問題是損傷變量形式如何確定,如何將損傷場耦合到無損材料的本構(gòu)關(guān)系中,從而得到蠕變損傷本構(gòu)模型。綜上,本文對下面幾個方面展開了研究并得到有關(guān)結(jié)論:(1)運用連續(xù)介質(zhì)損傷力學理論和應變等價原理,確定出能夠反映瀝青混合料變形的損傷變量,從而推導出蠕變損傷本構(gòu)模型的本構(gòu)方程。(2)根據(jù)ABAQUS用戶手冊,用FORTRAN語言二次開發(fā)出蠕變損傷模型的用戶材料子程序UMAT,以便后續(xù)進行有限元分析。(3)驗證該蠕變損傷模型及UMAT子程序的準確性,應用有限元數(shù)值分析法,通過UMAT子程序的接口將蠕變損傷本構(gòu)導入ABAQUS主程序,建立試驗模塊的三維有限元仿真模型,將損傷狀態(tài)下的計算結(jié)果與單軸靜載蠕變試驗結(jié)果進行對比。(4)建立瀝青路面的三維模型,對瀝青路面在不同荷載和不同溫度下進行有限元計算,研究其在有損傷和無損傷兩種狀態(tài)下的不同響應。從得到的計算云圖和數(shù)值結(jié)果可知,無論是變換荷載還是溫度,在不考慮損傷的情況下,等效蠕應變只出現(xiàn)兩個階段,即剛開始等效蠕應變隨時間逐漸增大,之后幾乎成水平線,呈現(xiàn)固結(jié)效應,這不符合實際情況,當考慮損傷時,應用本文建立的修正Burgers蠕變損傷模型結(jié)果曲線能夠很好地模擬瀝青混合料蠕變過程的三個階段,且破壞時間隨著荷載的增大和溫度的升高越來越短,同時我們還發(fā)現(xiàn)損傷值與等效蠕應變、豎向位移存在一定的關(guān)系,并且通過Origin8.0擬合出精度比較高的關(guān)系式,為瀝青混合料蠕變損傷的深入研究提供一些參考。
[Abstract]:Asphalt pavement has been widely used in road construction because of its good performance, although it has many advantages, but in the pavement construction stage, put into use stage and maintenance process will produce varying degrees of damage. With the continuous accumulation of these damages, the degree of cracking inside the pavement structure becomes more and more serious, which leads to the reduction of the bearing capacity of the pavement structure, the acceleration of the destruction of the pavement structure, and the reduction of its remaining service life. It is necessary to understand the evolution process of the damage and the influence of the damage on the internal force and deformation. On the basis of viscoelastic theory and damage mechanics, the creep damage constitutive model of asphalt mixture is derived, and the three-dimensional model is established by using finite element software ABAQUS. The change of mechanical response was studied under the condition of damage and non-damage. In this process, the main problem is how to determine the form of damage variables and how to couple the damage field into the constitutive relationship of lossless materials, and then obtain the creep damage constitutive model. In summary, the following aspects are studied in this paper, and the relevant conclusions are drawn: (1) using continuum damage mechanics theory and strain equivalence principle, the damage variables which can reflect the deformation of asphalt mixture are determined. Thus the constitutive equation of the creep damage constitutive model is derived. (2) according to the ABAQUS user manual, In order to verify the accuracy of the creep damage model and UMAT subroutine, the user material subprogram Umatt of creep damage model is developed by using FORTRAN language twice in order to verify the accuracy of the creep damage model and UMAT subprogram, and the finite element numerical analysis method is applied to verify the accuracy of the creep damage model. Through the interface of the UMAT subroutine, the creep damage constitutive model is introduced into the ABAQUS main program, and the three-dimensional finite element simulation model of the test module is established. Comparing the results of damage state with the results of uniaxial static creep test, the three-dimensional model of asphalt pavement is established, and the finite element calculation of asphalt pavement under different loads and temperatures is carried out. The different responses of the two states with and without damage were studied. From the calculated cloud diagram and numerical results, it can be seen that the equivalent vermicular strain has only two stages without considering the damage, that is, the equivalent vermicular strain increases gradually with time at the beginning, regardless of the change load or temperature. It is not in line with the actual situation. When damage is considered, the result curve of modified Burgers creep damage model established in this paper can well simulate the three stages of creep process of asphalt mixture. The damage time is shorter and shorter with the increase of load and temperature. At the same time, we also find that there is a certain relationship between the damage value and equivalent vermicular strain and vertical displacement. It provides some references for the further study of creep damage of asphalt mixture.
【學位授予單位】：西安建筑科技大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U416.2

【參考文獻】

相關(guān)期刊論文 前3條

1 盧應發(fā);吳延春;周盛沛;;飽和巖石各向異性彈塑性損傷模擬(英文)[J];華中科技大學學報(城市科學版);2006年04期

2 曹文貴,趙明華,唐學軍;巖石破裂過程的統(tǒng)計損傷模擬研究[J];巖土工程學報;2003年02期

3 付凱敏;黃曉明;;基于ABAQUS的修正Burgers蠕變模型二次開發(fā)[J];公路工程;2008年03期

相關(guān)博士學位論文 前1條

1 周勝田;航空發(fā)動機葉片疲勞的損傷力學研究及外物損傷影響[D];東北大學;2008年

相關(guān)碩士學位論文 前2條

1 李運軍;基于非局部損傷模型的混凝土損傷的數(shù)值模擬[D];合肥工業(yè)大學;2006年

2 曹鵬;混凝土塑性損傷模型及其ABAQUS子程序開發(fā)[D];沈陽工業(yè)大學;2009年

，

本文編號：1861179