Smash Lab is a new Discovery Channel series where a team of inventors try to solve an engineering challenge. The premise is quite nice, unfortunately I don't find the inventors in question to be particularly bright.

In the first episode they try to bomb-proof an existing building using spray-on Rhino Lining and some weird flaps for windows. The result were blown out windows and doors and a semi-stable wall that was crumbled inside. You can't really stop walls crumbling down after a car bomb right outside. But, the windows could easily be protected with the same type of stretchy plastic covering the glass from both sides in a way similar to Triplex car windshields. That would be much better looking than the window flaps they used. Also, if you're simulating a car bomb, don't forget to add nails, screws and/or ball bearing to create shrapnel. Overall: 5/10, can be improved a lot.

In the second episode they tried to use aerated concrete to improve the dividing barriers on highways. Both their designs failed miserably in a multitude of ways - they were hard to produce and failed to stop cars. The best they got was to slow down a heavy bus, but even that did not stop. I would propose a completely different design - an arrestor bed created from easy to manufacture blocks of solid concrete with a rectangular hole inside and a thin slab of aerated concrete on top of that hole. The blocks would be rectangular with a length that is good for transport and deployment. The crucial details are the width, height and internal structure. The height of the block must be surely higher than half the wheel diameter of a largest typical car. The width of the internal hole must such that a typical wheel would fit inside the rectangular central hole of the block after the top of the block breaks in. The wheel must fit both in a parallel and perpendicular fashion thus the width of the block must come to the typical wheel diameter. The blocks would be layed parallel to the road with around 10 blocks separating the traffic lines. If a car would weer onto such lane, the tops of the bricks will break very easily getting the wheels to fall into the hole in the block. The block walls will be much harder and will impact the wheelbase both slowing the car down and steering it so that it would be forced to move in the direction parallel to the traffic flow. In such direction of travel the car will continue to break off tops off the blocks until it slows down enough to fall beneath axle height at which point the concrete will crumble upwards bringing the car to a much faster stop. The car will be unlikely to cross to the opposite traffic because of the diversion effect from the block walls. Overall: 3/10, the inventors failed to achieve anything.

Crosscut of one block

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- is aerated concrete
# is solid concrete