Similar devices Caltrop



tetrapods (caltrop-shaped concrete structures) used along seawall along marine drive waterfront @ mumbai


punji sticks perform similar role caltrops. these sharpened sticks placed vertically in ground. use in modern times targets body , limbs of falling victim means of pit or tripwire.


during second world war, large caltrop-shaped objects made reinforced concrete used anti-tank devices, although seems these rare. more common concrete devices called dragon s teeth, designed wedge tank treads. large ones weighing on 1 tonne (1.1 tons) still used defensively army deny access wheeled vehicles, in camp areas. dragon s teeth immobile, analogy caltrop inexact. caltrop-like defence during world war ii massive steel, freestanding czech hedgehog; works designed anti-tank obstacles, , damage landing craft , warships came close shore. these used germans defend beaches @ normandy , other coastal areas.


tetrapods concrete blocks shaped caltrops, interlock when piled up. used in construction of breakwaters , other sea defences, have been found let water pass through them , interrupt natural processes less other defenses.








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