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利用RSM-SY5(T)型非金属声波检测仪对冻结重塑黄土进行单轴加载条件下的超声波纵波透射试验,研究声波在冻结重塑黄土受压过程中传播的速度特征,同时利用短时傅里叶变换及小波分析研究声波在冻结重塑黄土中传播的波形、频谱等特征.结果表明:冻结重塑黄土的纵波波速受温度和外荷载的影响,波速随温度升高而降低,在加载过程中随应变的增大大致呈现先增加后减小的趋势;冻结重塑黄土的单轴抗压强度与初始纵波波速值之间满足指数关系,相关性很好;随着加载的进行频谱形状发生变化,谱面积和主频减小;加载初期尾波不发育,随着应力的增大、裂纹的产生尾波逐渐发育;声波的特征参数能在一定程度上反映冻结重塑黄土加载过程中内部裂纹的发展情况.“,”The ultrasonic P-wave tests on frozen remolded loess under uniaxial loading are conducted by using RSM-SY5(T) nonmetal ultrasonic test meter to study the velocity characters of P-wave. The characteristics of acoustic waveforms and wave frequency spectra of frozen remolded loess are investigated by using the short-time Fourier transform and wavelet transform. The experimental results indicate that the P-wave velocity is affected by the temperature and external loads, and the velocity decreases with the increase of temperature and generally increases at first and then decreases with strain during the loading process. There is an exponential relationship between the uniaxial compressive strength and the initial P-wave velocity, and the correlation between them is very good. With the increase of external loading, the shape of spectral curve will change and the spectral area and main frequency will decrease. The coda waves are not developed at the initiation of loading and gradually develop with the increase of stress and the emergence of cracks. The characteristic parameters of acoustic waves can reflect the development of internal cracks of frozen remolded loess during loading to some extent.