【摘要】 为降低立井爆破施工的振动效应,以立井爆破中两圈直眼为原型,实施三种不同起爆延期的直眼微差爆破模型试验,并用UBOX-5016型爆破振动智能监测仪测试混凝土模型的爆破振动效应。实测爆破振动波表明,微差爆破可减少单段起爆药量、明显降低爆破振动效应;起爆延期25 ms时I段、Ⅱ段爆破振动波形彼此叠加,测点形成干扰降振效应,爆破峰值振动速度较小;起爆延期为50 ms时I段、Ⅲ段爆破振动波形彼此独立,峰值振动速度由单段起爆药量决定。竖向爆破振动波形频谱分析表明,微差爆破振动幅值明显低于齐发爆破,且波形复杂。微差爆破能显著降低爆破振动效应,主振频率较高。更多还原

【Abstract】 Taking two-circle vertical blast holes in vertical shaft blasting as prototype,tests for three millisecond blasting models with two-circle vertical blast holes were conducted to investigate the way to reduce the blasting vibration effect of vertical shaft blasting construction. The blasting vibration effects of a concrete model was monitored with a blasting vibration intelligent monitor UBOX-5016. The actual blasting vibration indicated that blasting vibration effect is reduced significantly by millisecond blasting through reducing the maximum charge; when the detonation time delay is 25 ms,two blasting vibration waves of segment I and segment Ⅱ overlap each other and the actual peak blasting vibration velocity is smaller due to interference effect of vibration reduction; when the detonation time delay is 50 ms,two blasting vibration waves of segment I and segment Ⅲ are almost independent and the actual peak blasting vibration velocity depends on the maximum charge. Spectral analyses were implemented for verticals blasting vibrations of three millisecond blasting models. It was shown that the amplitude of millisecond blasting is much lower than that of simultaneous blasting and the waveform of millisecond blasting is complex; the blasting vibration effect is reduced with millisecond blasting,its main vibration frequency is higher.更多还原