摘要
为研究膨胀土内部裂隙状况与频谱参数之间的关系,利用TH204型非金属声波检测仪,对干湿循环作用下不同控制含水率状态的膨胀土试件进行了声波测试。采用傅里叶变换,对声波信号进行了频谱分析,得到了膨胀土声波信号的主频率,并对干湿循环作用下膨胀土声波信号主频率的变化规律进行了探讨。研究结果表明:膨胀土声波信号的主频率随着循环次数的增加呈非线性衰减。控制含水率越大,主频率衰减越小。在相同的循环次数作用下,主频率随着控制含水率的增加呈线性衰减。主频率的变化能够反映膨胀土干湿循环过程中的内部裂隙发育程度和膨胀土的含水情况等特征。
In order to study the relationship between internal crack development of soil expansion and spectrum parameters, TH204 type of non-metallic acoustic detector was used for ultrasonic wave testing on expansive soil specimens with different control water contents under dry-wet circulation. The acoustic wave signals were carried out by spec- trum analysis of Fourier transform, and main frequency of the acoustic signals was obtained.and the variation of main frequency under wet and dry circulation was explored. The results show that the main frequency of expansive soil acoustic signals decays non- linearly with the increase of cyclic number under different control water content, and the greater control water content, the smaller main frequency attenuation.After the same cyclic number, the main frequency was almost linear attenuation with the increase of water content control.To a certain extent, the main frequency can reflect internal crack development and water content situation of expansive soil.
出处
《交通科学与工程》
2016年第3期25-29,共5页
Journal of Transport Science and Engineering
关键词
膨胀土
干湿循环
控制含水率
频谱分析
expansive soil
dry-wet circulation
control water content
spectrum analysis
