I don't think the shockwave would explode the tube. The in-rushing air would be equalizing the pressure. Yes, the more I've thought about this, the more I agre

I don't think the shockwave would explode the tube. The in-rushing air would be equalizing the pressure. Yes, the more I've thought about this, the more I agree. Moreover, I don't think the hypothetical shockwave would last all that long. As it moves down the tube, it has to drag an increasingly long column of air behind it, all of which is likely turbulent and definitely causing friction with the inside of the tube. This would slow and weaken the shock front considerably to the point that at some distance down the tube, the pressure would rise not suddenly, but slowly and evenly.