不同加载模式下沥青混凝土的断裂特性  

Fracture Performance of Asphalt Concrete under Different Loading Modes

作　　者：田小革[1] 韩海峰 李新伟 李思强 彭凯[1] 李绍鹏[1] 但瑞强 

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410004 [2]广州市高速公路有限公司,广东广州510288

出　　处：《建筑材料学报》2016年第4期758-761,共4页Journal of Building Materials

基　　金：国家自然科学基金资助项目(50878032);广东省交通运输厅科技项目(科技-2013-02-013)

摘　　要：通过改变带预切缝半圆形试件三点弯曲断裂(SCB)试验的支座位置和预制裂纹位置来改变试件的加载模式,对沥青混凝土试件进行了4种温度和5种加载模式的断裂试验,获得了临界应力强度因子(CSIF)随温度和加载模式的变化规律.结果表明:温度和加载模式对沥青混凝土抗裂性能有显著影响,在试验温度范围内,沥青混凝土抗裂性能随温度的降低而增大,在Ⅰ/Ⅱ型断裂的某个混合模式时最弱,纯Ⅰ型或纯Ⅱ型断裂试验会高估其抗裂性能,应以Ⅰ/Ⅱ型混合模式下的临界应力强度因子作为沥青混凝土抗裂性能评价指标.Positions of bearings and prefabricated crack of asphalt concrete（AC） semi-circle specimen were adjusted to determine cracking resistance under different loading modes. Three-point bending（SCB） tests were conducted at 4 temperatures and 5 loading modes, and the rules of the critical stress intensity factor （CSIF） and its variation with temperature and loading mode were obtained, which show that temperature and loading mode have obvious effects on the anti-cracking performance, the crack resistance increases with the decrease of temperature, and the minimum fracture resistance occurred under a specific mixed mode Ⅰ/Ⅱ fracture mode. So, a pure type Ⅰ or Ⅱ fracture test will over estimate the crack resistance, its critical stress intensity factor should be tested under a Ⅰ/Ⅱ mixed mode.

关 键 词：沥青混凝土 断裂性能 加载模式 临界应力强度因子 半圆形试件弯曲试验 

分 类 号：U414[交通运输工程—道路与铁道工程]