外保温系统高空坠落风险的热湿渐进性微损伤研究  

Thermal and wet progressive micro damage of high falling risk in building external wall systems

作　　者：姜伟[1] 郑鑫悦 李文谦 JIANG Wei;ZHENG Xinyue;LI Wenqian(School of Materials Science and Engineering,Tongji University,Shanghai 201804,China)

机构地区：[1]同济大学材料科学与工程学院,上海201804

出　　处：《新型建筑材料》2024年第8期1-6,12,共7页New Building Materials

基　　金：国家自然科学基金面上项目(52178240)。

摘　　要：基于断裂相场法的数值分析,构建细观-宏观尺度的计算模型,模拟外墙表面遭受炎热暴晒后突然降温情况下内部温度场与微观应力场,建立了热湿渐进性微损伤的评价模型,并通过粘接砂浆拉拔试验进行验证。结果表明:外保温系统外表面夏季升温至88.6℃再突然遭遇冰雹及强降雨降温至20℃时,细骨料和净浆受到的最大主应力值可达15 MPa,其厚度方向5 mm深度约100μm宽的裂纹已发展贯通,表明极端气候变化对保温系统结构完整性造成了实质性损害,外保温系统高空坠落风险迅速增大。A fine-macroscopic scale computational model was constructed based on the numerical analysis of the fracture phase field method to simulate the internal temperature field and microscopic stress field in the case of a sudden cooling of the exterior wall surface after being subjected to hot sunshine.An evaluation model of heat and humidity progressive micro-damage was established,which was verified by the bonded mortar pull-out test.The results indicate that when the external surface of the external wall system is subjected to a temperature increase of 88.6℃in summer and then a sudden decrease to 20℃by hail and heavy rainfall,the maximum principal stress value of fine aggregate and net mortar subjected to 15 MPa,respectively.Cracks with a depth of 5 mm and a width of 100 microns in the direction of the thickness were developed,which means that this kind of extreme climate change has caused substantial damages to the structural integrity of the heat preservation system,and the structural integrity of the heat preservation system is substantially damaged by this kind of extreme climate change.The risk of"high fall"of the external wall system increases rapidly.

关 键 词：外墙外保温系统 水泥基材料 微观应力 细观力学 

分 类 号：TU111.4[建筑科学—建筑理论]