【作者】 孟庆龙；

【导师】 刘寒冰；

【作者基本信息】 吉林大学 ， 道路与铁道工程， 2005， 硕士

【摘要】 沥青是一种典型的粘弹性材料,低温开裂和高温推移是沥青路面主要的破坏形式,严重损害了道路的使用性能,缩短了使用寿命。而目前尚未见到得到普遍承认的沥青高、低温性能评价方法,大多数是以经验法或半经验半理论法为主。沥青混凝土的蠕变现象普遍存在,蠕变性能对沥青的力学性能影响很大,随着粘弹性理论的发展,各国对沥青混凝土的蠕变现象越来越重视,对蠕变现象的研究越来越深入,蠕变性能作为评价沥青混合料的高、低温性能的重要指标之一,也越来越成为各国学者研究的重点。本文根据粘弹性理论和粘弹性材料的本构关系,从沥青混凝土小梁的弯曲蠕变实验入手,利用NU-10 气动多功能实验机,在-10℃时对沥青混凝土小梁进行了恒定载荷的弯曲蠕变实验。并通过数值分析,ANSYS 仿真,证明了沥青混合料的粘弹特性,验证了粘弹性本构关系理论,得到了AC-16,SMA-16 两种材料的应变曲线、劲度模量曲线、蠕变柔量曲线及-10℃的蠕变速率。为研究沥青混合料的力学性能,用蠕变速率评价沥青混合料的高、低温性能提供了一些有意义的数据,为路面设计提供了一些依据。并证明通过合理的选择理论公式,准确确定公式系数,利用先进的ANSYS 软件,完全可以模拟沥青混凝土小梁的粘弹性行为,从而实现对非线性、弹塑性、蠕变、粘弹性等问题的高度仿真。更多还原

【Abstract】 The creep phenomena of the bituminous concrete is widespread existence, thecreep generates great influence on mechanics performance of asphalt. Along with thedevelopment of the viscoelasticity theory, all countries value to the creep phenomena ofthe bituminous concrete more and more, and the research of the creep phenomena moreand more deeply. As creep performance is one of the important behavior of the heat, thelow temperature performance of the bituminous concrete, so creep performance is moreand more become the hot point of the research of all countries scholar.In this paper, according to the constitutive relation of the viscoelasticity theoryand the viscoelasticity material, we commence from the bent creep test of the smallbeam of the bituminous concrete. We make use of the multi-function machine(NU-10)which is air operated , Under the condition of -10℃, we carry on the test to the smallbeam of the bituminous concrete material, the research is under the constant function oflading, the response sweep creep phenomena of the small beam. Through numericalanalysis and ANSYS simulation research, we verified the characteristic of theviscoelasticity of the bituminous mixture, the theory of the viscoelasticity constitutiverelation and get the soft quantity curve of AC-16, SMA-16 these two kinds of stiffnessof material modulus curve and creep; we still obtain the speed of the creep, under thecondition of -10℃. Providing reference for the mechanics performance of bituminousmixture; For providing some data with the heat, the low temperature performance ofbituminous mixture that is tested by creep speed ratio; Provided some references for thepavement design. Through selecting reasonable theory formula, accurate formulacoefficient and advanced ANSYS software, we can imitate the viscoelasticity behaviorof the small beam of the bituminous concrete material completely, thus we carry outmany highly emulation, such as non-linear, Elasticity-plastic, creep and viscoelasticityetc.. This article includes five chapters totally, the third and fourth Chapter are theimportant part, and the fourth part is the role.The first Chapter introduces that the foreground, meaning, contents and methods ofthe research. The road engineering has the important function in developing nationalinfrastructure construction, the development of the infrastructure construction raises theliving quantity of whole Chinese people, the road engineering construction also embodythe advanced progress level of the nation and race. The asphalt road acquiring the moreand more application at the our country, because it is neat, seamless, comfortable whenthe car goes through and bear to whet, vibration small, the voice is low and the time ofconstruction is short and protect and maintain are simple etc. But the asphalt roadcurves the strength is lower, and is affected greatly by time and temperature, when thetemperature is low, it is easy to split, when the temperature is heat it produces totransform. With the development of the road engineering science and technology, putforward the higher request to the asphalt material, urge to study the work to further godeep in to open the exhibition. In addition to penetration, postponing the degree andsoftening point the three greatest indexes etc. which are commonly used currently,people put forward the frailty to order, contain wax content, a cent of clan successivelyanalytical, adhesion, and turn round the thin film oven aging etc. a series very rulesindex sign. And some researchers apply the fluid mechanics theories and methods tostudy the viscoelastic mechanics characteristic of the asphalt, creep, relaxation of stress,dependence relation of the asphalt function to temperature and time, and the strength,penetration index etc. and some indexes about the flowing change mechanics. The creepis one of the important index signs that is used to evaluate of the high low temperaturefunction of the asphalt mixture, being value by all countries scholar more and more.Making use of Creep Compliance, relaxation modulus, creep rate etc. the fluidmechanics index evaluate asphalt mixture’s high low temperature function this realm ofthat still have the very big research space. The second chapter has narrated the definition of creep, creep test and creep curve.In the meanwhile, the relationship among stress, strain, time and temperature of elasticmaterials such as metal and polymer have been narrated. It also has provided therelationship between strain and stress in the viscoelastic theory. The pavement materialof asphalt road is asphalt mixture, whose basic mechanical characteristic is particle andnon-elastic. Since asphalt mixture is composed of asphalt and graded broken stone, thegraded broken stone which take 95 percent in the asphalt mixture is particle material, asa result, the mechanical characteristic of asphalt mixture shows particle. Asphaltmixture is a typical elastic-visco-plastic synthesize. Within small deformation it is linearviscoelastic, while within large deformation it is viscoplastic, and in the transition rangeit is common viscoelastic. Generally speaking, all the asphalt road materials arenon-elastic, and in its common working range it mainly shows viscoelastic. Asphalt hasthe viscoelastic characteristic owing to the characteristics of asphalt. Creep andrelaxation usually exist in the actual working state. In the test and study of creep ofasphalt mixture, based on the theory of viscoelastic, describing different graded asphaltmixture accurately is the most important step.更多还原