摘要
In order to improve the compressive strength of xonotlite, the pretreated quartz powder, slaked CaO, additive, deionized water(water-solid ratio of 30) were placed in a magnetically stirred autoclave, and the corresponding products were obtained after incubating at 220 ℃ for 0, 1, 3 and 6 h, respectively to explore the synthetic process of xonotlite. In the prepared xonotlite powder, 0, 5%, 10%, 15% and 20%(by mass, the same hereinafter) of pre-treated ceramic staple fibers were added, and two sets of specimen with the specifications of φ50 mm×35 mm were molded by pressed filtration.One set of specimens were not sintered, and the other group was fired at 1 000 ℃ for 2 h to explore the effect of ceramic fiber addition on the compressive strength before and after sintering of xonotlite. The results show that C-S-H gel is first synthesized in the synthesis of xonotlite, and then the C-S-H gel is transformed to form tobermlite, at last tobermlite fully reacts to produce xonotlite. The addition of ceramic fiber enhances the compressive strength of the xonotlite before and after sintering. When the 15% ceramic fiber is added, the compressive strength is the highest. The specimens before and after the high temperature firing contain xonotlite phase and calcium silicate phase, respectively, and the compressive strength of the fired specimens is higher than that of the green ones.
In order to improve the compressive strength of xonotlite, the pretreated quartz powder, slaked CaO, additive, deionized water(water-solid ratio of 30) were placed in a magnetically stirred autoclave, and the corresponding products were obtained after incubating at 220 ℃ for 0, 1, 3 and 6 h, respectively to explore the synthetic process of xonotlite. In the prepared xonotlite powder, 0, 5%, 10%, 15% and 20%(by mass, the same hereinafter) of pre-treated ceramic staple fibers were added, and two sets of specimen with the specifications of φ50 mm×35 mm were molded by pressed filtration.One set of specimens were not sintered, and the other group was fired at 1 000 ℃ for 2 h to explore the effect of ceramic fiber addition on the compressive strength before and after sintering of xonotlite. The results show that C-S-H gel is first synthesized in the synthesis of xonotlite, and then the C-S-H gel is transformed to form tobermlite, at last tobermlite fully reacts to produce xonotlite. The addition of ceramic fiber enhances the compressive strength of the xonotlite before and after sintering. When the 15% ceramic fiber is added, the compressive strength is the highest. The specimens before and after the high temperature firing contain xonotlite phase and calcium silicate phase, respectively, and the compressive strength of the fired specimens is higher than that of the green ones.
