【作者】 曹辉；

【导师】 杨仁树；

【作者基本信息】 中国矿业大学（北京） ， 结构工程， 2009， 博士

【摘要】 针对低温高性能混凝土在深井井壁建设中应用的工程背景,对低温高性能混凝土的力学特性及抗冻性进行了研究。对C100高性能混凝土采用一次冻结法冻结,利用扫描电镜、压汞测孔法及工业CT技术等先进实验测试手段对低温高性能混凝土的微观形貌、孔隙结构等进行了研究,并进行了宏观力学试验；数值模拟了井筒的受力情况及工程原位实验测试力学性能;利用不同载荷下低温高性能混凝土试件的损伤分形维数描述了裂纹扩展情况。通过研究得出：利用本地原材料成功配制出的C100高性能混凝土在低温条件下仍具有较高的抗压强度和较好的抗冻性,从微细观结构方面解释了掺合料的作用机理；为研究高性能混凝土由微观结构到宏观力学性能的关系提供了试验方法及理论依据。研究表明：C100高性能混凝土能够满足低温施工需要,具有较好的社会经济效益。更多还原

【Abstract】 Based on the engineering background of high performance concrete (HPC) applications in the deep well construction at low-temperature, the mechanical properties and frost resistance of HPC are investigated. Many experiment methods, such as scanning electronic microscopy, mercury intrusion porosimetry, industrial CT and other advanced technologies, have been used to research on the microstructure and pore structure of C100 HPC which is frozen one time or freeze-thaw many times. And then the macro-mechanical test of C100 HPC is carried out. The force distribution of the shaft is simulated through numerical analysis. The crack development of C100 HPC at low temperatures with different loads is described by damage fractal dimensions. The study results show that C100 HPC at low temperatures, which is prepared by the local raw material, has high compressive strength and good frost resistance and the mechanism of admixtures is explained in the view of the micro-structure. The thesis provides test methods and theoretical basis to study the performance of HPC. The conclusion is that C100 HPC can meet the requirement of the low-temperature construction work, which will bring many social beneficial results.更多还原