Influence of gradation composition on crack evolution of stone mastic asphalt based on digital image processing

作     者：Liang, Hehao Guo, Hongjie Zhang, Jianjing Li, Hao Shi, Liwan Deng, Kailing 

作者机构：Foshan Univ Sch Civil Engn & Transportat Foshan Guangdong Peoples R China Hong Kong Polytech Univ Dept Civil & Environm Engn Hong Kong Peoples R China Foshan Transportat Sci & Technol Co Ltd Foshan Guangdong Peoples R China South China Univ Technol Sch Civil Engn & Transportat Guangzhou Guangdong Peoples R China 

出 版 物：《THEORETICAL AND APPLIED FRACTURE MECHANICS》 (Theor. Appl. Fract. Mech.)

年 卷 期：2025年第136卷

核心收录：

学科分类：08[工学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 080102[工学-固体力学] 

基　　金：Basic and Applied Basic Research Foundation of Guangdong Province  China [2021A1515110602  2022A1515010845] 

主　　题：Digital image processing Asphalt mixtures Stone matrix asphalt Semi-circular bending test Crack resistance 

摘      要：The resistance to cracking is one of the crucial considerations during the gradation design of stone mastic asphalt (SMA) pavements. However, the current insufficient understanding of the influences of gradation design on the crack evolution of SMA has led to the arbitrariness in the design of SMA. To fill this gap, this study proposes a digital image processing (DIP)-based method, combining smartphone video recording and semi-circular bending tests, to investigate the influencing mechanism of gradation composition changes on crack resistance and crack evolution of SMA with a nominal maximum aggregate size (NMAS) of 20 (SMA-20). The results proved the feasibility of using smartphone video recording and DIP to observe and measure the cracks evolution of asphalt mixtures. When evaluating crack resistance and crack propagation suppression, SMA with fine gradation generally performs better than SMA with coarse gradation, given the same NMAS. As loading deformation increases, the length and area of SMA cracks exhibit a linear growth trend. The change in crack area is reflected by the descending section of the SMA load-deformation (L-D) curve. The coarse aggregate content and specific surface area have a parabolic relationship with the evaluation indexes of crack resistance and propagation. Simply adjusting the gradation to be either coarser or finer does not enhance crack resistance and crack propagation suppression in SMA. Utilizing this parabolic relationship, the optimal ranges of coarse aggregate content and specific surface area can be separately determined to enhance crack resistance and crack propagation suppression of the same NMAS gradation. The findings of this study can provide valuable guidance and a theoretical basis for the targeted improvement of crack resistance during SMA gradation design. In addition, the study introduces a more convenient method for observing and measuring cracks in asphalt mixtures.