磷铝酸盐相变材料对受火混凝土高温损伤的同步修复研究  

Study on simultaneous repair of thermal-induced cracks within fire-exposed concrete by aluminophosphate phase change materials

作　　者：高芙蓉 姬永生[1,2,3] 马占国[1,2,3] 仇群彤 张洁[1,3,4] GAO Furong;JI Yongsheng;MA Zhanguo;QIU Quntong;ZHANG Jie(China University of Mining and Technology,State Key Laboratory for Geomechanics and Deep Underground Engineering,Xuzhou 221116,China;Jiangsu Vocational Institute of Architectural Technology,Jiangsu Collaborative Innovation Center for Building Energy Saving and Construct Technology,Xuzhou 221116,China;China University of Mining and Technology,Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering,Xuzhou 221116,China;Xuzhou College of Industrial Technology,School of Architecture Engineering,Xuzhou 221140,China)

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [2]江苏建筑职业技术学院江苏建筑节能与建造技术协同创新中心,江苏徐州221116 [3]中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116 [4]徐州工业职业技术学院建筑工程学院,江苏徐州221140

出　　处：《西安建筑科技大学学报（自然科学版）》2023年第5期661-668,共8页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家重点研发计划(2019YFC1904304);国家自然科学基金(51972337);江苏建筑节能与建造技术协同创新中心青年博士基金指导项目(SJXTBZ2102)。

摘　　要：火灾高温效应下,硅酸盐水泥基混凝土内形成大量宏、细、微观裂缝(或高温损伤),严重削弱受火混凝土的力学性能.如何有效修复高温损伤对改善受火混凝土力学性能具有重要意义.本文通过将研制的磷铝酸盐相变材料掺入硅酸盐水泥,高温-冷却过程中借助相变材料的固-液-固相变,实现同步修复受热水泥基体内高温损伤.通过确定磷铝酸盐相变材料对硅酸盐水泥高温后抗压强度、微观结构和矿物组成的影响规律,研究了磷铝酸盐相变材料对水泥基体内高温损伤的同步修复作用和对水泥高温后力学性能的改善效果.研究表明,掺加磷铝酸盐相变材料的水泥试件高温后微观结构完整,基体内裂缝明显少于纯水泥试件.高温后,掺加磷铝酸盐相变材料胶砂试件的抗压强度明显高于纯水泥胶砂试件.Under high temperature effect of fire,a large number of macro,fine and micro cracks(or thermal-induced cracks)are formed in Portland cement-based concrete,which seriously weakens the mechanical properties of fire-exposed concrete.Therefore,how to effectively repair thermal-induced cracks within concrete matrix is of great significance to improve mechanical strengths of fire-exposed concrete.In this investigation,a specially prepared aluminophosphate phase change material was mixed with Portland cement to realize simultaneous repair of thermal-induced cracks within concrete matrix by means of solid-liquid-solid phase transitions of the phase change material during heating and cooling process.The corresponding simultaneous repair effect on thermal-induced cracks within cement matrix and the improvement effect on mechanical properties of cement after high temperatures were investigated by determinations of changes in compressive strengths,micro structures and mineral compositions.The results show that the microstructure of cement specimens with aluminophosphate phase change materials is complete after high temperature,and the cracks in the matrix are significantly less than those of pure cement specimens.After high temperature,the compressive strength of the mortar specimens mixed with the aluminophosphate phase change material is significantly higher than that of the pure cement mortar specimens.

关 键 词：受火混凝土 高温损伤 磷铝酸盐相变材料 同步修复 力学性能 

分 类 号：TU525[建筑科学—建筑技术科学]