应力吸收层沥青混合料的半圆弯拉试验参数  

Semi-circular Bending Test Parameters of Asphalt Mixture with Stress-absorbing Layers

作　　者：申俊敏[1] 李志强[1] 李祖仲[2] 

机构地区：[1]山西省交通科学研究院黄土地区公路建设与养护技术交通行业重点实验室,太原030006 [2]长安大学材料科学与工程学院,西安710061

出　　处：《武汉理工大学学报》2012年第6期54-57,共4页Journal of Wuhan University of Technology

基　　金：交通运输部西部交通建设科技项目(2008 318 812 10);山西省交通厅科研计划项目(08-01)

摘　　要：针对应力吸收层组成材料及结构受力的特殊性,探索一种与之相匹配的低温抗裂性能的评价方法具有重要意义。在比较分析已有的沥青混合料低温抗裂试验方法的基础上,得出半圆弯拉试验方法用于评价应力吸收层混合料低温性能的合理性及优越性。采用三维有限元方法,建立带缺口的半圆弯拉试验模型,进行各试验参数下的应力分析。结果表明:试件的最佳厚度为50mm,底部拉应力基本上趋于稳定,受外部影响不大;随缺口宽度的增加,缺口处底部拉应力逐渐减少,基本上成线性关系,缺口宽度的最佳尺寸1.5mm;随缺口深度的增加,缺口处底部拉应力逐渐增大,在小于20mm时成线性增加,支座间距宜为0.8倍试件直径。Aiming at the unique constituent materials and stress state of the stress-absorbing layers, it is significant to develop a method to evaluate low temperature cracking performance. Comparative analysis was carried out on several common low-temperature cracking test methods, to determine the SCB test method as the rational evaluation way for low- temperature anti-cracking performance of stress-absorbing layers ultimately. It established a semLcircular bending test model with a notch based on three-dimensional finite element method, to analyze stress under the various test parameters. The results show that： the best thickness of specimen is 50 ram, while the tensile stress at the bottom of specimen be- comes stable, nm easily in{luenced by other factors. And then the reasonal width of the notch is 1.5 ram, when the width increases, the tensile stress of the bottom besides notch gradually reduces linearly. Furthermore, as the depth of notch increases until to 20 ram, the tensile stress of the bottom besides notch rises linearly. Finally, the suitable spacing of bearing is 0. 8 times of specimen diameter.

关 键 词：道路工程 应力吸收层 低温抗裂 半圆弯拉试验 试验参数 三维有限元 

分 类 号：U416.224[交通运输工程—道路与铁道工程]