Steel cross beams on the beach?

Question

What are the steel cross beams on the beaches the USA stormed during the World Wars?

Answer 1

Those are often refered to as tank traps. Tracked vehicles cannot drive over them--if they try they find themselves having to lift thier own weight well before the center of gravity. They are placed close enough together that tracked vehicles cannot get through.

They are relatively easily cleared, but they do cannalize the traffic and the breaching teams that remove them are exposed to enemy overwatch.

On a beach, they can do the same to landing craft, but they have to be deloyed much thincker and in greater depth due to tidal action.

Answer 2

World Wars????

Only in one my lad, and that was on the shores of France in WW2.

The steel beams were known as "tetrahedral" because of there geometric shape:

In order to achieve Field-Marshal Rommel’s strategy of blocking the Allied landing forces a vast numbers of obstacles designed to hamper the approach of the assault barges were placed along the beaches.

These obstacles were designed to trap the barges, where they would crash, become impaled, torn apart or explode, and included “Czech hedgehogs”, “nutcrackers”, “Belgian gates” and “tetrahedra”. Trenches and anti-tank walls or “dragon’s teeth” also blocked the beach exits.

Answer 3

Tank traps & landing boat obstagles.

Answer 4

"TANK TRAPS" designed for the beaches where we were invading to keep us from off-loading our tanks and APC's .