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so you see how bridges take enormous
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amount of loads of vehicles passing one
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after the others allowing them to pass
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an obstacle like a river a roadway or a
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Waterway well certainly they take the
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load of heavy-loaded trucks but still
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manages to stay strong for Lifetime like
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around 100 years or so but the golden
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question we've been asked for is what
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makes Bridges so strong you know the
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strength of a bridge is its Essence and
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the top priority of any bridge is safety
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a pedestrian bridge must be strong
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enough to support people cyclists
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animals and light Vehicles so that's
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where experts called Engineers come in
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to design elements or components so
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strong to carry the designed or intended
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load for the bridge to carry that much
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load the engineers uses different types
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of materials like concrete steel or
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maybe wood they arrange these members or
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elements of a bridge in a geometry their
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combination their quality and their
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quantity everything is crucial to make
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Bridge strong but why we need to build
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strong Bridges well that's because we
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don't want the bridge to collapse so our
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main objective is to determine the
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design load for a bridge and satisfy
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that with the design elements let's find
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out what happened when we overload a
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bridge with more people or
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stuff so you see it collapses that's why
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we need to build stronger Bridges and we
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do this by using stronger elements and
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stronger materials take a look at this
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simple Bridge we call it as beam bridge
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now if this bridge is of a wooden
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cardboard it will take not much load but
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if we build it using a steel plate it
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will take much more load in comparison
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so you see selecting the type of
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material is critical in making stronger
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Bridges the other factor to make
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stronger Bridges is geometry take a look
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at this bridge made of truss elements
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you'd see how its elements are slim and
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slender but what's the secret here well
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the secret here is its geometry simple
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it's geometry I mean its elements are
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arranged in a way that all the members
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are in either compression or tension
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I've gotten other explain video about
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different stresses so make sure to have
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a look at that video well the bridge
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here is a steel trust bridge and to your
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surprise it has to be strong you know
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why because it has to take the load of
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heavy trains if you take a closer look
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at the bridge truss you'd see it has got
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some triangles doing the trick well if
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you know it or not the triangles are
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strong when used in buildings when you
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apply the load on the side of the
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triangle it bends but it won't go
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anywhere if you apply the force on the
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tip that's the trick behind why the
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bridges made with trusses are stronger
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and can carry heavy loads so when a car
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travels on a truss Bridge all these
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triangles distributes the force in a way
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that it collectively converts forces in
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to tension or compression another type
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of bridge we normally see is a
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suspension bridge one famous example of
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a suspension bridge is a Golden Gate
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Bridge now let's see how we build
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suspension bridges suspension bridges
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are made to carry and distribute the
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load as tension we support the deck of
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the bridge with suspending it using
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tension elements these tension elements
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are nothing but ropes or wires that
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tightly carry the deck these wires are
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then hung on the tall towers that take
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the load and distribute it on the soil
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below the river at the extreme ends we
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got the anchors that stabilize the
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bridge overall now the other most common
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types of bridge is that of reinforced
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concrete these Bridges use concrete that
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is reinforced with steel bar carefully
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placed inside during casting Bridge
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elements most concrete bridges are
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founded on pile Foundation that are dug
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deep beneath the river above these piles
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we got a pile cap giving a foundation
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for the bridge Piers these Bridge peers
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then carry the load of the deck slab now
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to your surprise concrete is an element
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that's strong in compression but once we
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add rebar inside it becomes stronger in
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tension too that's how the engineers
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design rein forced concrete bridges that
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we see as flyovers or Bridge decks so
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you see it's not just the material that
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makes Bridges strong but it's also the
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geometry or the smart design with how
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the bridge is built that's for passing
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by and spending time with us I hope it's
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worth it for you if you've learned
4:18
something and want to ask more give us a
4:20
quick note in the comment section below
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we'll reach out to you thanks
