沥青混凝土起裂韧度试验研究  

Experimental study on initial fracture toughness of asphalt concrete

作　　者：曹国瑞 卿龙邦 刘天云[1,2] 陈礼彪 曾俊铖 CAO Guorui;QING Longbang;LIU Tianyun;CHEN Libiao;ZENG Juncheng(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,China;School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China;Fujian Expressway Group Co.,Ltd.,Fuzhou 350001,China;Fujian Expressway Science&Technology Innovation Research Institute Co.,Ltd.,Fuzhou 350001,China)

机构地区：[1]清华大学水圈科学与水利工程全国重点实验室,北京100084 [2]清华大学水利水电工程系,北京100084 [3]河北工业大学土木与交通学院,天津300401 [4]福建省高速公路集团有限公司,福州350001 [5]福建省高速公路科技创新研究院有限公司,福州350001

出　　处：《水力发电学报》2024年第8期56-63,共8页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(51779069,52066027);福建省科技重大专项资助(2021HZ026010)。

摘　　要：开展了沥青混凝土半圆弯曲断裂试验,获得了裂缝扩展全过程荷载-裂缝口张开位移曲线,结合线性相关陡降法研究了温度、加载速率及预制裂缝长度对沥青混凝土起裂韧度的影响。应用数字图像相关方法对沥青混凝土起裂及裂缝扩展全过程损伤变形特性进行了研究。结果表明:线性相关系数陡降法所得起裂荷载处于损伤产生时刻对应荷载范围内,验证了该方法应用于沥青混凝土起裂韧度研究的可行性。随温度和预制裂缝长度增加,起裂韧度逐渐降低;随加载速率增大,起裂韧度呈现出上升趋势。Semi-circular bending(SCB)fracture tests on asphalt concrete were conducted in this study,and load-crack opening displacement curves of its crack propagation process were obtained.We examine the effects of temperature,loading rate,and initial crack length on its initial fracture toughness,using the steep drop method of linear correlation coefficients;a digital image correlation method was used to study its damage and deformation characteristics at the stages of crack initiation and crack propagation.Research findings show that at the damage position,the initial cracking load obtained using this steep drop method is within the ranges of experimental load,verifying the rationality of the method in studying the initial fracture toughness.This toughness decreases gradually with the temperature and initial crack length,while increases with the loading rate.

关 键 词：沥青混凝土 起裂韧度 数字图像相关方法 裂缝扩展 起裂荷载 

分 类 号：TU528.42[建筑科学—建筑技术科学]