摘要
对高温作用下的素混凝土、纳米SiO_(2)混凝土、玄武岩纤维增强纳米SiO_(2)混凝土进行抗压、劈裂抗拉和抗折试验,建立了混凝土强度预测模型。结果表明:各组混凝土抗压强度均在400℃时达到峰值,此时各组混凝土较常温时提高范围为3.5%~6.8%,随后逐渐降低;劈裂抗拉强度和抗折强度均随着温度的升高而逐渐降低,800℃时,素混凝土的劈裂抗拉强度残余率和抗折强度残余率分别为27.6%、36.2%。纳米SiO_(2)的掺入提高了素混凝土的抗压、劈裂抗拉和抗折强度。掺入玄武岩纤维后的纳米SiO_(2)混凝土在800℃高温后的抗压强度、劈裂抗拉强度、抗折强度最大分别提高了33.7%、15.6%、17.2%。建立的高温作用后混凝土强度预测模型的精确度较高。
The compressive,splitting tensile and flexural tests of plain concrete,nano-SiO_(2) concrete and basalt fiber nano-SiO_(2) concrete under high temperatures were carried out,and the prediction model of concrete strength that was established.According to the results,the compressive strength of each group reached a peak value at 400℃,at that time,each group of concrete at normal temperature increased by about 3.5%to 6.8%,and then decreased gradually,and the splitting tensile strength and flexural strength decreased gradually with the increase of temperature,at 800℃,the residual ratios of cracking and pulling strength and the residual ratios of flexural strength were 27.6%and 36.2%,respectively.Adding nano-SiO_(2) could improved the compressive,splitting tensile and flexural strength of plain concrete.The compressive strength,splitting tensile strength and flexural strength of nano-SiO_(2) concrete after being subjected to 800℃high temperature were increased by 33.7%,15.6%and 17.2%respectively.The accuracy of concrete strength prediction after being subjected to high temperatures was high.
作者
刘华新
郑太元
LIU Huaxin;ZHENG Taiyuan(Southeast University,Key Laboratory of Concrete and Pre-Stressed Concrete Structures of Ministry of Education,Nanjing 210018,China;School of Civil Engineering and Architecture,Liaoning University of Technology,Jinzhou 121001,China)
出处
《工业建筑》
CSCD
北大核心
2022年第2期18-23,107,共7页
Industrial Construction
基金
东南大学混凝土及预应力混凝土结构教育部重点实验室开放课题(CPCSME2017-03)
辽宁省教育厅科研基金项目(JJL201915404)。
