摘要
为研究纳米材料的微观结构对混凝土宏观力学性能的影响,采用声发射试验和数值模拟相结合的方法,研究纳米混凝土在循环载荷作用下的声发射特性.结果表明:纳米混凝土具有明显的Kaiser效应,但存在一定的应力水平范围.与普通混凝土相比,由于受到纳米SiO2微观作用的影响,纳米混凝土在前3次加载过程中,声发射能量高、幅值大、活性强.但在第4次加载时,由于承载能力得到提高,纳米混凝土声发射能量累积曲线的变化相对平缓.RFPA数值模拟结果与试验结果具有一致性,其应力图和声发射图能够形象地表征试件裂纹的扩展过程和破裂位置.这有助于深入了解纳米混凝土损伤过程的声发射特征.
To study the influence of nano material microscopic structure on the macro-mechanical properties of concrete,using AE test and numerical simulation methods,the AE characteristic of Nano-concrete under cyclic loading was investigated.The results show that the Nano-concrete has Kaiser effect,however,it occurs in a certain stress level range.Compared with ordinary concrete,the Nano-concrete has higher AE energy,larger AE amplitude and stronger AE activity during the first 3 loading processes due to the micro influence of Nano-SiO2.Nevertheless,in the 4th loading,the AE energy cumulative curve of Nano-concrete is relatively flat because of the improvement of the bearing capacity of Nano-concrete.The numerical simulation results of RFPA and experimental results are consistent.The stress diagram and AE figure are able to image the characteristics of the specimen crack propagation process and the rupture position,which helps an in-depth understanding on the AE characteristics of Nano-concrete during its damage process.
出处
《辽宁工程技术大学学报（自然科学版）》
CAS
北大核心
2012年第6期875-880,共6页
Journal of Liaoning Technical University (Natural Science)
基金
江西省研究生创新专项基金资助项目(YC10A034)
