【作者】 张檑；

【导师】 吕建国；

【作者基本信息】 中国地质大学（北京） ， 地质工程， 2011， 硕士

【摘要】 通过采用中国地质大学(北京)力学实验室的WAW-2000DL电液伺服试验系统及SAEU2S声发射仪,研究了不同强度混凝土试件单向受载全过程的声发射参数特征,建立了强度损伤耦合模型并对混凝土试件的凯塞效应和费利西蒂效应的关系进行了分析。1.通过对不同强度的混凝土试件进行单轴压缩试验,同时记录试件破坏全过程的声发射特征参数,经过分析发现声发射信号与混凝土试件的力学性质联系紧密,各强度的混凝土试件应力应变曲线与声发射特征参数吻合的较好,试件在发生破坏时声发射事件率发生突变。2.通过对不同强度的混凝土试件进行单轴劈裂拉伸试验,同时记录试件破坏全过程的声发射特征参数,并与试件的单轴压缩试验结果进行对比分析,发现混凝土试件在单轴压缩和劈裂拉伸过程中既有相同点同时也存在着较大的差异。3.通过对9种不同强度的混凝土试件进行单轴压缩试验,在试验分析的基础上,从混凝土损伤破坏的微观机理出发,通过理论分析提出了一个符合weibull分布的统计损伤演化模型,并根据试验中所获得的声发射数据对该模型进行拟合。将理论模型与实际结果对比后发现,两者比较吻合,验证了该理论模型的正确性。4.对强度为C30的混凝土试块进行循环加载试验,发现混凝土存在着明显的凯塞效应现象,通过对费利西蒂效应的分析研究,更加准确的确定了混凝土试件的凯塞效应的应力范围。更多还原

【Abstract】 By using China university of geosciences (Beijing) mechanics laboratory WAW2000DL electro-hydraulic servo test system and SAEU2S acoustic emission apparatus, studied in different strength concrete specimens of the whole process of the unidirectional under load by acoustic emission parameters characteristics, established strength damage models of concrete and analyze the relationship between Kaiser effect and Felicity effect.1. According to the uniaxial compression test of the different strength of concrete,and record the whole process of acoustic emission damage characteristic parameters,then found that acoustic emission signal and mechanical properties of concrete specimens linked closely,the strength of concrete specimens stress-strain curve and acoustic emission characteristic parameters are fitted well,and when the specimen destroyed,acoustic emission event rate mutated.2. According to the uniaxial splitting tensile test of different strength of concrete specimens,record the whole process of acoustic emission damage characteristic parameters,and compare with the uniaxial compression test results ,then found the concrete samples which under uniaxial compression and splitting tensile process have similarities but also exist larger difference.3. Through the uniaxial compression test of 9 different strength of concrete, based on the analysis of the damage from the microscopic mechanism of concrete and the theory analysis ,then put forward a weibull distribution with the statistical damage evolution model, and gain the model fitting test data of acoustic emission. Contrast the theoretical model and actual results,found that both are consistent with the theory,verify the validity of the model.4. On the strength of concrete test blocks for C30 cycle loading test and found concrete exist obvious Kaiser effect,through the analysis of Felicity effect,more accurately determine the Kaiser effect of concrete samples of stress range.更多还原