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本文报导了用４种频率（１００ｋＨｚ、１５０ｋＨｚ、５００ｋＨｚ和１５００ｋＨｚ）的超声波，对长江口和杭州湾的水底浮泥在不同重度下测得的声速和重度之间、声衰减与重度之间以及在一定重度下频率与声衰减之间的变化关系曲线。实验结果表明：在相同条件下，杭州湾浮泥的声衰减比长江口浮泥的声衰减大一点（约１０％）。在重度１０．０～１６．０ｋＮ／ｍ３之间，声衰减与重度成线性关系，声衰减与频率约成一次方关系；声速随重度的增加变化不大（约±２％），在低频率（１００ｋＨｚ和１５０ｋＨｚ）上出现一个明显的极小值，例如，长江口浮泥重度１４．５ｋＮ／ｍ３时，声速最小，约为１４６０ｍ／ｓ，杭州湾浮泥重度１３．５ｋＮ／ｍ３时，声速最小，约为１４４０ｍ／ｓ。
This paper reports the effects of sound attenuation and severity measured at different intensities on the bottom mud of the Yangtze Estuary and Hangzhou Bay at four frequencies (100 kHz, 150 kHz, 500 kHz and 1500 kHz) Under certain severity, the relationship between frequency and sound attenuation curve. The experimental results show that under the same conditions, the sound attenuation of the floating mud in the Hangzhou Bay is a little larger (about 10%) than the sound attenuation of the mud in the Yangtze Estuary. Acoustic attenuation is linearly related to the severity at the range of 10.0 ~ 16.0kN / m3. The acoustic attenuation is approximately a linear relationship with the frequency. The velocity of sound varies little with the increase of the intensity (about ± 2%), (100kHz and 150kHz). For example, when the suspended sediment of the Yangtze River estuary is 14.5kN / m3, the sound velocity is the smallest, about 1460m / s, and the suspended sediment of Hangzhou Bay is 13.5kN / m3. The sound velocity The smallest, about 1440m / s.