中文摘要：

运用湿度扩散理论、统计学方法以及损伤力学方法建立了水泥基复合材料湿度扩散与裂纹扩展之间耦合作用的数值模型。研究表明：裂缝是影响湿度扩散过程的一个重要因素,对湿度扩散路径的影响尤为显著。当有裂缝存在时,湿度扩散的范围更深、更广,相应的湿度应力则会更大,不利于裂缝的预防与控制。湿度的变化引起的干缩应力将促使裂缝的进一步扩展,同时,裂缝的扩展又将导致湿度扩散范围的增大,从而反过来促进裂缝的扩展,这是一个湿度-应力-损伤耦合作用的过程。因此,对已有裂缝的水泥基复合材料进行裂缝修补工作有利于提高其耐久性。

英文摘要：

On the basis of humidity diffusion theory,statistical methods and damage mechanics,a numerical model has been proposed to study the coupling effect between humidity diffusion and crack growth processes in cement-based composite.The investigation indicates that crack is an important factor which significantly influence the humidity diffusion processes,especially the effect on the humidity diffusion paths.The humidity would diffuse a large scope as there are cracks in the cement-based composite,resulting in the increase of shrinkage stress which is not benefit for crack control.Further more,shrinkage stresses often result in cracks,which enhanced the humidity diffusion processes.It is a humidity-stress-damage coupling processes.Therefore,it is important to repair the existing cracks of cement-based composite as soon as possible to improve its durability.