不同成型方法级配碎石的抗变形性能

Study of anti-deformation properties of grade macadam with different molding methods

为研究不同成型方法对不同级配的级配碎石抗变形性能的影响,选取了振动压实法和静压法2种成型方法,悬浮密实结构(GD)和多级嵌挤骨架密实结构(TK)2种不同级配的级配碎石,利用回弹模量表征级配碎石的弹性变形特性,提出了稳定指数(SI)来评价级配碎石的塑性变形特性.采用2种方法成型试件后,在最佳含水量下测定其回弹模量;借鉴沥青混合料车辙试验来研究级配碎石的抗塑性变形能力,根据最大干密度和最佳含水量,按98%的压实度,利用振动压实法和静压法成型级配碎石试件,测定试件含水量为W_0、0.5 W_0和0的动稳定度.研究发现,不同成型方法下级配碎石的弹、塑性变形相差较大,且振动压实法级配碎石回弹模量为静压成型法的1.56~1.77倍,稳定指数为1.52~1.56倍.

In order to study the influence of molding methods on grade macadam deformation characteristics with different grades, selecting two kinds of molding methods, i.e. vibratory compaction method and stat- ic method, two different grading graded macadams which are suspend-dense structure （GD） and multilevel embedded squeeze skeleton solid structure （TK）, representing grade macadam deformation characteristics in use of resilient modulus, a stability index （SI） is proposed to evaluate grade macadam plastic deforma- tion characteristics. And then molding specimens with above-mentioned two methods, resilient modulus at the optimum moisture content is measured. The grade macadam plastic deformation resistance is studied with reference to rutting test of asphalt mixture. Based on the maximum dry density and optimum moisture content, according to 98% of compaction, the dynamic stability of specimens which are molded by vibra- tion and static method with W0, 0.5W0 and 0 water content is measured. The study shows that there is a big difference in elastic and plastic deformation between specimens which are molded by different molding; the resilient modulus and stability index of vibratory compacting specimens are 1.56-1.77 and 1.52-1.56 times higher than static compacting specimens.