沥青混合料在螺旋处的离析试验  

Experiment on asphalt mixture segregation in screw conveyor

作　　者：谢立扬[1] 张晨光[1] 赵利军[1] 

机构地区：[1]长安大学道路施工技术与装备教育部重点实验室,陕西西安710064

出　　处：《长安大学学报（自然科学版）》2013年第4期12-17,28,共7页Journal of Chang’an University(Natural Science Edition)

基　　金：国家自然科学基金项目(51105043)

摘　　要：为准确掌握摊铺过程中沥青混合料在螺旋分料器中的离析原因及分布规律,基于混合料在螺旋内的运动特性,分析了螺旋作用下混合料颗粒的轴向速度及圆周速度与螺旋半径、节距、转速及摩擦因数之间的关系,并通过现场试验给出了混合料离析在螺旋中的分布规律。结果表明:沥青混合料在螺旋作用下产生的离析主要受螺旋结构和运动参数的影响;随着螺旋半径的增大,混合料的轴向速度单调递增,圆周速度先增大后减小,并在螺旋主要工作区(螺旋半径14～20cm)圆周速度与轴向速度较为接近,能够通过改变螺旋转速、螺旋与混合料的相对位置来调整混合料的运动特性,限制混合料颗粒的离析;螺旋上部的沥青含量比其底部高出2%,螺旋中部的沥青含量比两侧高出0.7%,沥青混合料级配均值在其规定的范围内,但螺旋上部的混合料规格偏细;采用混合料满埋螺旋的方法,可解决螺旋悬挂处沥青含量的离析,但不能解决螺旋上下处的离析。In order to exactly find out segregation reasons and segregation distribution regularities of asphalt mixture in screw conveyor during the paving process, based on the kinetic characteris-tics of mixture, this paper analyzed the relationship between the particles＇ axial and circumferen tial velocity and radius, pitch, rotational speed and friction coefficient under the action of screw conveyor. Meanwhile, field tests were conducted to get the segregation distribution regularities of asphalt mixture in screw conveyor. The results indicate that the mixture segregation is mainly affected by the spiral structure and the kinetic parameters. With the increase of radius, the particles＇ axial velocity monotonically increases, the circumferential velocity increases first and then decreases and the circumferential velocity is approximately equal to the axial velocity in the primary working range （radius 14-21 cm）. So the segregation can be restricted by changing the rotational speed of screw conveyor and the relative position of screw conveyor and asphalt mix ture. The asphalt content in the upper part of the screw is 2% higher than that in the bottom, the asphalt content in the central part of the screw is 0.7 % higher than that in both sides, the de viation of asphalt mixture gradation is in the specified range, but the asphalt mixture in the upper part of the screw contains more fine aggregate. Using the method of completely burying the crew conveyor, we can solve the asphalt content segregation occurring in the crew suspension. But the segregation between the upper and the lower part of the crew conveyor still exists. 2 tabs, 9 figs, 11 refs.

关 键 词：道路工程 沥青摊铺机 螺旋布料器 沥青混合料 离析试验 

分 类 号：U415.521[交通运输工程—道路与铁道工程]