【作者】 初伟；

【导师】 王为标； 王文进； 张应波；

【作者基本信息】 西安理工大学 ， 水工结构工程， 2004， 硕士

【摘要】 近年来，土石坝沥青混凝土心墙在国内外有了很大的发展，但是目前对沥青混凝土材料的基本性能还不太了解，影响着这种坝型的发展。本文通过三轴压缩蠕变试验和振动三轴试验，借助粘弹性理论和土动力学理论，对土石坝沥青混凝土心墙材料的两个重要性质——蠕变性能和动力特性进行了初步的研究。用三元固体模型和Burgers四元模型来拟合沥青混凝土的蠕变曲线，发现Burgers模型能够更好的描述沥青混凝土的蠕变过程，为土石坝沥青混凝土心墙的有限元计算提供参数。通过振动三轴试验获得沥青混凝土材料的动力参数，并结合西安理工大学陈存礼老师的研究成果。发现动应力与动应变的关系较好地符合双曲线规律，最大动模量E_dmax和最大剪切模量G_dmax随着温度的降低、围压和固结比Kc的增大而增大。围压和固结比对沥青混凝土的阻尼比没有多大影响，阻尼比随着温度的升高有着降低的趋势。在动应力条件下，振次几乎对动应变中的弹性应变的变化没有影响。在同一固结比和同振次条件下，动应力对动残余应变的影响约呈线性关系，且振次对动残余应变的影响呈逐渐增大的变化关系。在不同围压和8.8℃条件下，对沥青混凝土施加较大的动应力，在100振次以内所产生的动应变是很小的，即使施加3000～5000振次，轴向总应变也仅为1％～2％左右。沥青混凝土似乎不存在动强度破坏问题。更多还原

【Abstract】 Asphalt concrete core for embankment dams have got notable development in recent years, but the fundamental properties of asphalt concrete cores is not known clearly which has a hold on wide use of this kind of dams. Preliminary research on creep and dynamic characteristics, which are two important properties of asphalt concrete cores for embankment dams, through triaxial compression creep tests and dynamic triaxial test with the aid of the viscoelastic theory and the soil dynamics theory. Using the three梡arameter solid model and the Burgers four-parameter model to fit the creep curve separately, it was found that the Burgers model can describe the creep process more well, and then provide parameters for finite element analysis of asphalt concrete cores for embankment dams. The dynamic parameters of the asphalt concrete can be obtained through dynamic triaxial test, combined with the CunLi Chen’s studying results, discovering that the dynamic stress-strain relationship obeys the hyperbolic model well, and the maximum dynamicmodulus Edmax and the maximum shear modulus Gdmax increasing along with the decreasing of the temperature and the increasing of consolidation ratio Kc. Confining stress and consolidation ratio have little effect on damping ratio of the asphalt concrete, and the damping ratio has decreasing tendency along with the increasing of the temperature. Vibration times hardly have effect on the changing of the elastic strain in the condition of the dynamic stress. Under the same consolidation ratio and the vibration times, effect of the dynamic stress on the dynamic residual strain shows linear relationship, and effect of the vibration times on the dynamic residual strain increasing. In the condition of the different confining stress and the temperature of 8. 8癈, dynamic strain of the asphalt concrete is very little within 100 vibration times under rather big dynamic stress, the total axial strain is only about 1%~2% within 3000~5000 vibration times. It seems that no dynamic strength destroy problem for the asphalt concrete.更多还原