基于细观孔隙结构的排水沥青混合料劈裂损伤分析

Splitting Damage Analysis of Drainage Asphalt Mixture Based on Micropore Structure

为了深入研究大孔隙排水沥青混合料在荷载作用下的损伤机理,采用CT扫描技术并结合数字图像处理技术,对不同孔隙率的沥青混合料试件的微观结构进行了有限元建模,并在沥青砂浆和沥青砂浆-集料界面插入具有双线性牵引分离定律的内聚力单元,以实现虚拟劈裂试验过程中的裂纹扩展。通过对沥青混合料试件开裂过程中的应力分布和损伤行为的分析得出沥青混合料孔隙率对拉压应力分布、荷载-位移曲线、劈裂强度以及开裂过程所需能量的影响规律。

In order to further study macropore drainage asphalt mixture under the load of damage mechanism,based on the CT scan technology combining with digital image processing technology,with different porosity of the asphalt mixture finite element modeling,the microstructure of the specimens and the asphalt mortar and asphalt mortar-aggregate interface insert has a bilinear traction separation law of unit cohesion,in order to realize the crack propagation in virtual splitting test.Based on the analysis of stress distribution and damage behavior in cracking process of asphalt mixture,the influence law of porosity of asphalt mixture on tension and compression stress distribution,load-displacement curve,splitting strength and energy required in cracking process is obtained.