A series of blast experiments with and without vibration-isolating trenches were implemented in the blast containment chamber with an elliptic cone which having an inside diameter of 2 m and a wall thickness of 0. 4 rn. And the vertical and horizontal ground vibration velocities at 6 different points on the surrounding ground of the chamber were measured. The experimental results show that the ground vibration duration is less than 0. 2 seconds, the frequency spectra of the vertical and horizontal vibrations are in the 20-500 Hz and 200-800 Hz ranges, respectively. The horizontal velocity amplitudes after attenuation by the trenches are one-tenth of those before attenuation, as well as one-fourth to one-third for the vertical velocity amplitudes. But the trenches have no obvious effect on the frequency spectra of the ground vibration waves. The vibration-isolating trenches with lm depth have no attenuation effect on the blast seismic waves, but the attenuation effect will be remarkable when the depths of the trenches are 1. 5-2. 0 times as long as the wavelengths of the Rayleigh waves.%对内径2 m、壁厚0.4m的椭球封头爆炸塔进行有、无隔振沟条件下的对比爆炸实验,并监测塔体周边6个测点的地表竖向及水平方向的振动速度.研究结果表明:地表质点的振动持续时间小于0.2s,竖向振动频谱在20～500 Hz范围内,水平方向振动频谱则在200～800 Hz范围内；隔振沟使水平方向振动幅度衰减至原来的1/10,对竖向振动幅度衰减至原来的1/4～1/3,对地表振动频率无明显影响；爆炸塔隔振沟的深度为1 m时,对爆炸地震波无任何衰减作用,仅当深度达到1.5～2.0倍瑞利波波长时(5.6～7.5 m)才会产生明显的隔振效果.
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