کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
259023 | 503626 | 2012 | 9 صفحه PDF | دانلود رایگان |
In this paper, autogenous self-healing of engineered cementitious composites (ECCs) subjected to two different cyclic freeze/thaw (FT) regimes is investigated, which are water and deicing salt freeze/thaw cycles, respectively. To evaluate self-healing degree in preloaded ECC after FT cycles, direct tensile test, sorptivity test and ultrasonic pulse test are conducted for self-healed ECC with different preloaded strain levels varying from 0.5 to 3.0%. The experimental results show that self-healing of ECC mainly depends on preloaded strain levels which have a close relation with maximum crack width of preloaded ECC. Higher the preloaded strain level, lower self-healing degree. For ECC with preloaded strain levels of less than 1.5%, mechanical and transport properties of self-healed ECC can recover as well as those of virgin ECC without any damage. Water and deicing salt freeze/thaw cycles can weaken the properties of ECC. However, self-healing degree of ECC in water freeze/thaw cycles is higher than that in deicing salt freeze/thaw cycles. According to XRD analysis, chemical compositions of white self-healed cracks are calcium carbonate and calcium hydroxide.
► Preloaded ECC can self-heal in freeze/thaws cycles.
► Higher preloaded tensile strain levels, lower recovery of tensile properties.
► Self-healing degree of ECC in water freeze/thaw is higher than that in deicing salt.
► Chemical compositions of self-healed cracks are calcium carbonate and calcium hydroxide.
Journal: Construction and Building Materials - Volume 34, September 2012, Pages 522–530