森林工程
森林工程
삼림공정
FOREST ENGINEERING
2012年
2期
62-67
,共6页
道路工程%沥青路面%横向裂缝%纵向裂缝%有限元%裂缝扩展
道路工程%瀝青路麵%橫嚮裂縫%縱嚮裂縫%有限元%裂縫擴展
도로공정%력청로면%횡향렬봉%종향렬봉%유한원%렬봉확전
road engineering%asphalt pavement%transverse crack%longitudinal crack%finite element method%crack extend
基于自上而下的表面纵、横向疲劳裂缝严重影响沥青路面的使用品质,首先分析表面疲劳裂缝的形成机理,然后采用奇异等参元法及断裂力学理论,应用有限元软件ABAQUS,建立20结点等参立方体单元的有限元模型,数值计算路面表面纵、横向疲劳裂缝扩展,探讨表面纵、横向裂缝疲劳扩展的规律。计算表明:①表面纵、横向裂缝扩展只考虑偏载作用,随着裂缝向下扩展,其K2是增大到一个峰值后,再由此下降。裂缝扩展前期,纵、横向裂缝的K2差别不大,而在中后期,纵向裂缝的K2要大于横向裂缝。②各路面结构参数中面层厚度h1和模量E1及基层模量E2对表面纵、横向裂缝扩展影响较大,其它参数(土基模量E0、底基层厚度h3和模量E3、基层厚度h2)则影响很小。
基于自上而下的錶麵縱、橫嚮疲勞裂縫嚴重影響瀝青路麵的使用品質,首先分析錶麵疲勞裂縫的形成機理,然後採用奇異等參元法及斷裂力學理論,應用有限元軟件ABAQUS,建立20結點等參立方體單元的有限元模型,數值計算路麵錶麵縱、橫嚮疲勞裂縫擴展,探討錶麵縱、橫嚮裂縫疲勞擴展的規律。計算錶明:①錶麵縱、橫嚮裂縫擴展隻攷慮偏載作用,隨著裂縫嚮下擴展,其K2是增大到一箇峰值後,再由此下降。裂縫擴展前期,縱、橫嚮裂縫的K2差彆不大,而在中後期,縱嚮裂縫的K2要大于橫嚮裂縫。②各路麵結構參數中麵層厚度h1和模量E1及基層模量E2對錶麵縱、橫嚮裂縫擴展影響較大,其它參數(土基模量E0、底基層厚度h3和模量E3、基層厚度h2)則影響很小。
기우자상이하적표면종、횡향피로렬봉엄중영향력청로면적사용품질,수선분석표면피로렬봉적형성궤리,연후채용기이등삼원법급단렬역학이론,응용유한원연건ABAQUS,건립20결점등삼립방체단원적유한원모형,수치계산로면표면종、횡향피로렬봉확전,탐토표면종、횡향렬봉피로확전적규률。계산표명:①표면종、횡향렬봉확전지고필편재작용,수착렬봉향하확전,기K2시증대도일개봉치후,재유차하강。렬봉확전전기,종、횡향렬봉적K2차별불대,이재중후기,종향렬봉적K2요대우횡향렬봉。②각로면결구삼수중면층후도h1화모량E1급기층모량E2대표면종、횡향렬봉확전영향교대,기타삼수(토기모량E0、저기층후도h3화모량E3、기층후도h2)칙영향흔소。
The top-down fatigue cracks on the surface seriously affect the using quality of asphalt pavement. Formation mecha- nism of surface fatigue cracks was analyzed. Then, based on singular and other parameters together with fracture mechanics theory, a finite element analysis model of 20-node isoparametric elements was established by the FEM software ABAQUS. The surface cracks in transverse and longitudinal direction were numerically analyzed, and the extend rules were studied. Results indicate that: ( 1 ) the propagation of surface cracks in transverse and longitudinal direction is dominated by deflection load. In the course of crack propaga- tion, K2 first increases to the top then drops down slowly. In the initial crack propagation, the difference of K2 is small, but in latter phases, K2 in longitudinal direction is greater than that in transverse direction. (2) Among all the parameters of each road surface structure, the most important influence factors affecting the crack extend are thickness h1 , modulus E1 and base modulus E2. Other parameters, such as subgrade modulus E0, sub-base thickness h3, modulus E3, and base thickness h2 have little effect.