气泡帷幕对爆破冲击波的削减效果及鱼类安全防护研究

Reduction effect of bubble curtain on blasting shock wave and fish safety protection

航道整治工程中多采用水下爆破的方式对碍航礁石予以清除,爆破产生的冲击波会对鱼类安全存在一定的影响,目前多采用气泡帷幕的方式削减冲击波峰值压力。研究通过构建更接近实际的气泡帷幕数值模型,探明不同布置方式下气泡帷幕对爆破冲击波压力的削减效果及其作用下的鱼类存活最小体长。研究结果表明:气泡帷幕对冲击波压力的消减程度在前半段(65%~69%)大于后半段(10%~12%)。随着气泡体积占比的上升,气泡帷幕对冲击波峰值压力的削减率也随之提升,但当气泡体积占比达到40%后,削减率增幅减小且趋于平缓。气泡帷幕距爆源10、15、20 m下的鱼类存活最小体长分别为20~34、14~30、12~24 cm,气泡帷幕厚度为2、3、4 m下鱼类存活的最小体长分别为12~24、10~22、6~17 cm。研究结果可为航道整治工程实施下鱼类资源的保护提供理论依据。

In the waterway improvement projects,underwater blasting is often used to remove the reefs that obstruct navigation,and the shock waves generate by blasting would affect the safety of fish.At present,bubble curtain is commonly used to reduce the shock waves peak pressure.In this study,a numerical model of bubble curtain is constructed to investigate the reduction effect of bubble curtain on blasting shock wave pressure and the minimum length of fish survival under the effect of different arrangements.The results show that the reduction of shock wave pressure by bubble curtain is greater in the first half(65%-69%)than in the second half(10%-12%).With the increased of bubble volume proportion,the reduction rate of bubble curtain on shock wave peak pressure also increases.However,when the bubble volume proportion reaches 40%,the increase of reduction rate decreases and tends to level off.The minimum length of fish surviving under the bubble curtain 10,15,and 20 m from explosive sourceare 20~34,14~30,and 12~24 cm respectively,and the minimum length of fish surviving under the bubble curtain thickness of 2,3 and 4 m is 12~24,10~22 and 6~17 cm respectively.The results of the study can provide theoretical basis for the protection of fish resources under the implementation of waterway regulation projects.