Some Companies have no alternative BUT to close since LAWSUITS have all but eliminated their operations.
Some Companies, like DART for example, have been paying $1,000,000.00 a year for Life to some Families for Deaths in Truck CAUSED accidents/wrecks even though DART is a Owner Operator only Company.
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The Cable Barriers are capable of stopping 4 wheelers yet the posts are ALUMINUM which will shear when hit by 40 tons as have been verified numerous times.
The other idea of using ALUMINUM Guard Rails is just as inefficient.
I've never understood the uses of such weak Post design. Using wood (4x4) isn't much better. Using solid STEEL would well stop a 40 ton vehicle HOWEVER such could cause other problems like simply stopping the frame while the Body including the Drive train (motor, transmission) continues or just disassembles into varying directions possibly inflicting more mayhem.
It IS COSTLIER to use heavier materials, however such uses have lasted for DECADES as older Roads (2 lanes, old Truck routes) can attest.