受载岩石与混凝土声发射特性对比实验研究

Contrast Study on the Acoustic Emission Characteristics of Compressive Rock and Concrete Through Experiment

通过室内加载岩石和混凝土的实验方法,测试了两类不同性质的岩石以及混凝土的破裂全过程的力学特征及其声发射特性,得到了岩石和混凝土破坏全过程力学特性曲线、声发射事件累积数、声发射事件率等相关曲线及参数,研究了声发射事件数、事件率、应力水平与时间参数之间的关系。通过对比岩石和混凝土声发射特性,指出了岩石声发射特性与混凝土声发射特性的相似与不同之处,以及两类不同性质岩石本身声发射特性的区别。研究着重讨论了一次性加载过程中混凝土与塑性阶段明显的岩石在加载接近峰值强度时都出现明显的"耗时"现象,指出存在这种现象的试样在此阶段声发射事件率出现明显下降,出现声发射相对平静,而对于塑性阶段不明显岩石来说,这一阶段则基本不存在明显的"耗时"现象,声发射的监测中也没有相对平静现象。此外,还对时间参数在声发射监测研究中的重要性进行了总结和分析,指出常规室内岩石力学研究中可以忽略的时间参数在声发射研究中应该被足够地重视。

The full failure,of loading rock samples and concrete samples were tested and its mechanics characteristics and Acoustic Emission （AE） characteristics were studied.The curves of mechanics characteristics and AE accumulative total and AE rate of concrete and rock failure were got.And the AE features including the relationships between AE and time,AE and stress were studied.By comparing the AE characteristics between rock,their different and similar AE characteristics were pointed out.The time-consuming phenomenon was discussed to both rock samples and concrete samples whose plastic deformation is obvious when stress is close to peak value strength at the process of one time loading.It was pointed out that the AE rate of those samples which have this time-consuming phenomenon will be declined and AE quietude will also appear in this stage.But for brittle rocks,neither this timeconsuming phenomenon nor AE quietude will appear.In addition,the value of the parameter of time was analyzed and summarized in AE monitoring and studying.Time parameter should be paid more attention to in AE studying despite it could be ignored in general indoor rock mechanics experiment research.