Narrator: TODAY ON "IMPOSSIBLE ENGINEERING"...
THE WORLD'S MOST MASSIVE GATEWAYS.
ONE TOWERS ABOVE THE WATERS.
AND THE OTHER CHANNELS THROUGH THEM.
THIS IS ONE OF THE BIGGEST PROJECTS EVER MADE.
Narrator: RELYING ON PIONEERING INNOVATIONS OF THE PAST.
Dr. Sheehy: IT FEELS MORE LIKE A CATHEDRAL
THAN A FUNCTIONAL STRUCTURE.
Narrator: IT TOOK REVOLUTIONARY ENGINEERING
TO MAKE THE IMPOSSIBLE POSSIBLE.
-- Captions by VITAC -- www.vitac.com
CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS
FOR MORE THAN 100 YEARS, THE PANAMA CANAL
HAS PROVIDED A MASSIVE SHIPPING GATEWAY
BETWEEN THE PACIFIC AND ATLANTIC OCEANS.
BUT BY 2006,
ENGINEERS HERE FIND THEMSELVES
IN A MASSIVE PREDICAMENT.
Ferreira: THE PROBLEM WITH THE ORIGINAL PANAMA CANAL
IS THAT THE SHIPS ARE GROWING,
AND THE SHIP CANNOT FIT THROUGH THE EXISTING CANAL.
Narrator: SINCE IT WAS COMPLETED IN 1914,
SHIPS HAVE INCREASED AROUND THREE TIMES IN SIZE.
AND SIMPLY CANNOT SQUEEZE THROUGH THE ORIGINAL CANAL,
FORCING THESE BIG SHIPS ON A COSTLY TWO-WEEK DETOUR
AROUND SOUTH AMERICA.
WE NEED A BIGGER CANAL.
Narrator: THE SOLUTION?
THE PANAMA CANAL EXPANSION PROJECT,
ONE OF THE BIGGEST INFRASTRUCTURE PROJECTS
IN THE WORLD.
THIS MASSIVE CONSTRUCTION INCLUDES SIX NEW LOCK FLIGHTS,
EACH ONE SPANNING THE LENGTH OF FOUR SOCCER FIELDS.
THE GATES SEPARATING EACH CHAMBER
REACH THE HEIGHTS OF AN 11-STORY BUILDING.
TO MAKE WAY FOR THEM,
A STAGGERING 5.3 BILLION CUBIC FEET OF EARTH
MUST BE DREDGED.
A WHOPPING 155 MILLION CUBIC FEET OF CONCRETE
ENCASE OVER 215,000 TONS OF STRUCTURAL STEEL.
THE RESULT IS A 48-MILE-LONG CANAL
THAT CAN FINALLY ACCOMMODATE
SOME OF THE LARGEST SHIPS IN THE WORLD.
BUT BUILDING THIS MASSIVE GATEWAY IS A TALL ORDER.
Ferreira: WE HAVE BIG CHALLENGE HERE.
YOU HAVE TO UNDERSTAND, THE CANAL
HAS TO GO OVER MOUNTAINS IN ORDER TO DO THIS.
Narrator: OVERCOMING THIS OBSTACLE
WOULD BE IMPOSSIBLE
WITHOUT THE GREATEST INNOVATORS FROM THE PAST.
DURING THE 17th CENTURY, KING HENRY IV OF FRANCE
WANTED TO BUILD A CANAL TO LINK THE LOIRE AND THE SEINE.
BUT BETWEEN THE TWO RIVERS, A RIDGE RISES UP 130 FEET.
TO MAKE BOATS SAIL UPHILL,
31-YEAR-OLD HYDRAULICS ENGINEER HUGUES COSNIER
DEVELOPED AN INGENIOUS SOLUTION.
Dr. Morgan: HERE IN THE VILLAGE OF ROGNY-LES-SEPT-éCLUSES
IS THE MOST EXTRAORDINARY EXAMPLE
OF WHAT COSNIER ACHIEVED.
IT'S A STAIRCASE LOCK,
THE FIRST OF ITS KIND IN EUROPE.
SEVEN INTERCONNECTED CHAMBERS ENABLE THE BOATS
TO RISE UP THE STEEP TERRAIN.
Narrator: COSNIER'S INGENIOUS STAIRCASE
LIFTED BOATS 10 FEET AT A TIME.
THE BOAT WOULD COME IN FROM THE LOWER LEVEL,
AND THE GATE WOULD BE CLOSED BEHIND IT,
SEALING IT INTO THE CHAMBER.
THE NEXT STAGE WAS TO SLOWLY BRING IN THE WATER...
...UNTIL THEY WILL NATURALLY EQUALIZE.
NOW THE DOOR COULD BE EASILY OPENED
WITHOUT ANY WATER FLUSHING THROUGH,
AND THE BOAT COULD SAFELY TRAVEL THROUGH.
Narrator: BY USING A TOTAL OF 36 LOCK CHAMBERS,
COSNIER SURMOUNTED THE 130-FOOT-HIGH RIDGE
AND MADE THE ENTIRE CANAL SYSTEM POSSIBLE.
TO BUILD THE PANAMA CANAL OVER THE MOUNTAINS,
ENGINEERS SUPER-SIZE
HUGUES COSNIER'S LOCK STAIRCASE CONCEPT ON AN EPIC SCALE.
NEEDLESS TO SAY, THE STRUCTURES ARE MASSIVE,
UNIQUE DESIGNS.
WE HAVE THREE CHAMBERS.
EACH RAISES THE VESSEL 9 METERS.
SO THE VESSEL GOES 27 METERS HIGH
THROUGH AN ARTIFICIAL LAKE,
AND IT GOES DOWN THE SAME THREE STEPS DOWN THE OTHER SIDE.
Narrator: HOWEVER, GETTING SHIPS THROUGH THE MOUNTAINS
IS ONLY HALF THE BATTLE.
THE NEW LOCKS REQUIRE MORE THAN 20,000 WORKERS
EXCAVATING WELL OVER 2 BILLION CUBIC FEET
OF ROCK AND EARTH.
THAT'S 2.6 MILLION DUMP-TRUCK LOADS.
BUT ENGINEERS MUST MODIFY THE LANDSCAPE
NOT ONLY ABOVE THE WATER,
BUT ALSO BELOW THE WATER.
DEEPENING AND WIDENING THE CHANNELS FOR NAVIGATION
PRESENTED QUITE A BIG ENGINEERING CHALLENGE,
'CAUSE YOU HAVE VERY HARD ROCK.
Narrator: TO CUT OUT THIS ROADBLOCK,
ENGINEERS MUST RELY ON THE D'ARTAGNAN,
ONE OF THE WORLD'S BIGGEST CUTTER SUCTION DREDGERS.
THE D'ARTAGNAN USES
A COMPUTER-CONTROLLED ROTATING CUTTER TOOL
AND SMASHES THE BEDROCK TO SMITHEREENS.
BUT THE DREDGING AND EXCAVATION
PRODUCE HUGE AMOUNTS OF WASTE MATERIAL.
TO FIND AREAS WHERE WE COULD,
YOU KNOW, DEPOSIT 50, 60 MILLION CUBIC METERS OF MATERIAL
IS NOT AN EASY THING.
Narrator: COMPOUNDING THIS PROBLEM IS AN ALTOGETHER UNUSUAL ONE.
THE ADJACENT WASTELANDS ARE DEADLY.
THIS WAS A CONTAMINATED AREA.
THIS WAS NOT A PLACE WHERE YOU COULD WALK OR USE IT,
BECAUSE IT WAS WITH UNEXPLODED ORDINANCE.
Narrator: THIS FORMER U.S. ARMY FIRING RANGE
IS LITTERED WITH LIVE AMMUNITION.
TO DISPOSE OF THE 2.1 BILLION CUBIC FEET OF EARTH
ON THESE TREACHEROUS LANDS,
THE ENGINEERS MUST DRAW ON ONE OF HISTORY'S GREAT INNOVATIONS.
IN THE 1940s, THE SOUTH COAST OF ENGLAND
WERE HEAVILY FORTIFIED AGAINST INVASION FROM THE NAZIS.
Steele: WHEN YOU'VE GOT A LANDSCAPE
THAT'S LITTERED WITH UNEXPLODED ROUNDS,
THERE'S ALWAYS THE RISK THAT SOMEONE'S GONNA SET
ONE OF THEM OFF, AND PEOPLE ARE GOING TO GET KILLED.
Narrator: REPRESENTING A LAND MINE,
THIS WEIGHT DEMONSTRATES THE PROBLEM THEY PRESENT
WHEN BURIED.
AND NOW, IT'S PRETTY HARD
TO TELL THERE'S ANYTHING THERE AT ALL.
Narrator: DURING WORLD WAR II,
THE GERMANS ALSO USED LAND MINES AGAINST THE ALLIES.
TO HELP THE ALLIES,
JOZEF KOSACKI DEVISED A CLEVER SOLUTION.
Steele: THIS IS WHAT HE DEVELOPED.
SO, WHAT WE'VE GOT HERE ARE OUR TWO COILS
WHICH WE'RE GOING TO BE USING, OBVIOUSLY, TO DETECT THE METAL.
SO LET'S PLUG THIS THING TOGETHER AND SEE HOW IT WORKS.
WE'VE SET UP THE CONDITIONS FOR A FEEDBACK CIRCUIT.
WE'VE GOT THE INPUT OF THE AMPLIFIER
BEING POWERED BY ONE OF THE COILS,
WHICH THEN GOES OUT AGAIN AMPLIFIED
AND POWERS THE SECOND COIL.
AND THAT MEANS THAT IF THERE'S ENOUGH CONNECTION
BETWEEN THOSE TWO COILS,
WE'VE GOT THE POTENTIAL FOR THE SAME SIGNAL TO GO 'ROUND
AND 'ROUND AND 'ROUND IN A LOOP AND GET LOUDER AND LOUDER,
JUST LIKE WHAT HAPPENS IF YOU TAKE A MICROPHONE TOO CLOSE
TO A SET OF SPEAKERS.
[ QUIET HUMMING ]
AND ALL IT TAKES IS THE PRESENCE OF A LITTLE BIT OF METAL
JUST TO INCREASE THE COUPLING BETWEEN THOSE TWO COILS.
OH, THERE WE GO.
AND THEN, THERE WE GO, DEAD EASY.
WE FOUND THAT FAKE MINE THAT WE PLANTED EARLIER.
¶¶
Narrator: JOZEF KOSACKI INVENTED THE FIRST
PRACTICAL, PORTABLE METAL DETECTOR.
Narrator: THE PANAMA CANAL EXPANSION PROJECT UTILIZES
THE MODERN-DAY EQUIVALENTS OF KOSACKI'S DETECTOR
TO CLEAR THE UNEXPLODED WEAPONRY.
[ DEVICES WHINING ]
WE GOT COMPANIES THAT WERE EXPERTS AT DOING THIS.
THEN THEY PILED THEM OVER TOGETHER
AND BLEW THEM UP, IF THEY WERE LIVE.
Narrator: IN ALL, THE TEAMS REMOVE MORE THAN 3,000 PIECES
OF LIVE AMMUNITION AND DESTROY THEM.
AND WE CLEANED 460 HECTARES OF UNEXPLODED ORDINANCE.
Narrator: ENGINEERS COMPLETE THE EPIC CONSTRUCTION
IN JUNE 2016,
AND THIS COLOSSAL CONTAINER SHIP
IS ABOUT TO PUT THIS NEWLY DESIGNED, MASSIVE GATEWAY
TO THE TEST.
[ SPEAKING SPANISH ]
THE BIG CHALLENGE WAS TO BUILD A CANAL
SO WE COULD FIT THIS TYPE OF SHIP.
THIS SHIP ARE GOING INTO A LOCKS
THAT HAS 427 METERS IN LENGTH
BY 55 METERS IN WIDTH.
Narrator: TO REACH THE ELEVATED SECTION OF THE CANAL,
ENGINEERS MUST GUIDE THESE ENORMOUS SHIPS
THROUGH TWO GIGANTIC STAIRCASE LOCKS
AT EITHER END OF THE CANAL
THAT WILL LIFT THE SHIP NEARLY 90 FEET.
¶¶
BUT SIMPLY SUPER-SIZING EXISTING DESIGNS ISN'T ENOUGH.
ALTHOUGH WE HAVE LOCKS AROUND THE WORLD THAT ARE WIDER,
WE DO NOT HAVE ANY THAT ARE WIDER, LONGER,
AND DEEPER AND, IN ADDITION,
THAT HAVE THE THREE STEPS.
THE BIGGEST CHALLENGE THAT WE ENCOUNTERED
IN THE DECISION ON THE NEW LOCKS
WAS THE TYPE OF GATES THAT WE WOULD USE.
Narrator: BUT TO CREATE LOCK GATES POWERFUL ENOUGH
TO WITHSTAND THE TREMENDOUS PRESSURE OF WATER,
ENGINEERS MUST LOOK TO THE PAST
TO ACHIEVE MORE IMPOSSIBLE ENGINEERING.
Narrator: THE PANAMA CANAL EXPANSION PROJECT
IS ONE OF THE MOST MASSIVE GATEWAYS IN THE WORLD.
BUT TO ENGINEER LOCK GATES
THAT CAN WITHSTAND THE TREMENDOUS PRESSURE OF WATER,
ENGINEERS MUST LOOK TO THE PAST.
THE SPRAWLING CITADEL OF SUOMENLINNA IN FINLAND
IS HOME TO ONE OF EUROPE'S OLDEST OPERATING DRY DOCKS.
BUT KEEPING THE WATER OUT OF THE DRY DOCK
HINGES ON THE EFFECTIVENESS OF THE GATES.
Lind: TRADITIONAL DOCK GATES SWING OPEN LIKE LARGE DOUBLE DOORS
BUT WERE DIFFICULT TO MAINTAIN
AND PUT STRAIN ON THE INFRASTRUCTURE OF THE DOCK.
WORSE STILL, SOME DOCKS USED TEMPORARY GATES
MADE OUT OF WOOD AND MUD THAT HAD TO BE DESTROYED
EVERY TIME THE LOCK NEEDED RE-FLOODING.
Narrator: TO RESOLVE THIS PROBLEM,
BRITISH NAVAL ARCHITECT SAMUEL BENTHAM
CAME UP WITH A REVOLUTIONARY IDEA IN 1796,
AN EXAMPLE OF WHICH STILL STANDS HERE TODAY.
Lind: IT'S AMAZING.
IT REALLY IS MASSIVE.
Narrator: CALLED A SHIP CAISSON,
SAMUEL BENTHAM'S LOCK IS AN INGENIOUS CROSS
BETWEEN A GATE AND A BOAT.
¶¶
TODAY, WE CAN SEE THIS 200-YEAR-OLD INVENTION
IN ACTION.
Narrator: RIGHT NOW, THE CAISSON GATE IS FULL OF WATER.
BUT FIRST, WORKERS MUST OPEN THE VALVES
FROM THE CANAL TO FLOOD THE DRY DOCK.
¶¶
Lind: NOW THE WATER IN THE LOCK HAS REACHED THE LEVEL
WHERE WE CAN START PUMPING THE WATER OUT OF THE GATE,
AND THEN THE GATE STARTS FLOATING.
Narrator: DESPITE WEIGHING 90 TONS,
THE FLOATING GATE MOVES BY HUMAN POWER ALONE.
Lind: BENTHAM'S INVENTION IS IN ACTION,
AND IT'S AMAZING.
IT HAS REALLY STOOD THE TEST OF TIME.
¶¶
Narrator: TODAY, THE PANAMA CANAL EMPLOYS 16 NEW LOCKS,
BUT WITH A MASSIVE SPIN
ON BENTHAM'S FLOATING CAISSON GATE.
THESE GATES ROLL IN AND OUT OF POSITION.
THIS CAN ONLY BE ACHIEVED BECAUSE THEY FLOAT.
George: THE GATES ARE SUPPORTED ON AN UPPER AND A LOWER WAGON,
BUT THE GATES ACTUALLY FLOAT,
AND ONLY ABOUT 15% OF THE WEIGHT
IS ACTUALLY CARRIED BY THE WAGONS.
Narrator: BUT FOR THE $5 BILLION EXPANSION
TO BE WORTH THE COST,
OPERATORS MUST KEEP TRAFFIC MOVING SMOOTHLY.
De Marotta: WE ONLY HAVE ONE LANE.
WE CANNOT SHUT IT DOWN FOR ANYTHING.
WE HAVE TO BE OPEN 24/7.
Narrator: BUT SHIPPING ACCIDENTS DO HAPPEN.
[ AIR HORN BLOWS ]
SO HOW DO YOU PROTECT
A 224,000-TON FULLY LADEN CARGO SHIP
LIKE THIS ONE FROM DISASTER?
Chong: STOP THE BACK THRUSTER, AMIDSHIPS.
-AMIDSHIPS! -AMIDSHIPS!
Narrator: THIS WOULD BE IMPOSSIBLE
WITHOUT THE INNOVATORS OF THE PAST.
¶¶
IN THE 19th CENTURY,
THE DEVELOPMENT OF A WORLD-CHANGING MATERIAL
CAME FROM AN UNLIKELY PLACE -- BILLIARDS.
IN THEIR ATTEMPTS TO DEVELOP NEW MATERIALS
FOR BILLIARD BALLS,
ENGINEERS DEVELOPED MANY FORMS OF PLASTIC,
INCLUDING ONE CALLED PARKESINE.
PARKESINE AND OTHER EARLY PLASTICS
WERE A COMBINATION OF CELLULOSE,
NITRIC ACID, AND SULFURIC ACID.
WHILE IT COULD BE EASILY MOLDED INTO A VARIETY THINGS,
THEY WERE PRONE TO CRACKING.
Narrator: SO AMERICAN INVENTOR JOHN WESLEY HYATT
TRIED USING A DIFFERENT ADDITIVE
TO IMPROVE THE NITROCELLULOSE MATERIAL.
HYATT DISCOVERED THE IMPORTANCE OF ONE KEY INGREDIENT, CAMPHOR,
FOUND IN THE WOOD OF A LAUREL TREE.
IF WE TAKE THIS BOWL OF PASTA
TO REPRESENT MOLECULES OF NITROCELLULOSE,
YOU CAN SEE IN THEIR CURRENT STATE,
THEY REALLY STICK TOGETHER,
AND IT WOULDN'T MAKE A VERY USEFUL PLASTIC.
SO WHAT WE NEED IS A SHORT, LITTLE MOLECULE
TO GET IN BETWEEN THESE AND FREE THEM UP
SO THEY CAN SLIDE PAST ONE ANOTHER.
SO IF WE TAKE THIS OLIVE OIL TO REPRESENT THE CAMPHOR,
HYATT REALIZED BY ADDING JUST THE RIGHT AMOUNT,
HE COULD FREE THE MOLECULES UP
AND CREATE A MOLDABLE PLASTIC.
HE CALLED HIS MATERIAL CELLULOID,
AND IT'S CONSIDERED TO BE THE FORERUNNER
OF MODERN PLASTICS.
Narrator: SUBSEQUENT GENERATIONS OF THESE PLASTICS
NOW MAKE IT POSSIBLE FOR TODAY'S COLOSSAL CARGO SHIPS
TO SQUEEZE SAFELY THROUGH THE NEW PANAMA CANAL ROUTE.
De Marotta: SO WE PUT FENDERING ALL OVER.
THERE'S ABOUT 6,000 FENDERS BETWEEN ATLANTIC AND PACIFIC
TO PROTECT THE VESSEL
AND THE LOCKS FROM HITTING EACH OTHER.
Narrator: THESE FENDERS ARE COVERED
WITH ULTRA-HIGH-MOLECULAR-WEIGHT POLYETHYLENE.
THIS REVOLUTIONARY THERMOPLASTIC
ENABLES THE HULL TO SLIDE ALONG THE FENDERS' SURFACE
RATHER THAN CATCH,
WHILE RUBBER ABSORBS ANY IMPACT.
AND THE STAKES FOR GETTING THESE VESSELS THROUGH WITHOUT INCIDENT
ARE SKY HIGH.
THAT SHIP IS PAYING $850,000
JUST TO COME THROUGH THE CANAL.
Narrator: BUT OPERATING THESE GIGANTIC 11-STORY-HIGH LOCKS
COULD CREATE A HUGE ENVIRONMENTAL HEADACHE.
ONE OF THE MAIN RESOURCES FOR THE CANAL TO OPERATE
IS WATER, FRESH WATER.
NO WATER, NO TRANSIT OF SHIPS.
Narrator: TO KEEP IT RUNNING,
THE CANAL RELIES ON THE HUMAN-MADE RESERVOIR,
LAKE GATUN.
WE HAD TO BE VERY CAREFUL
ON HOW WE'RE GOING TO USE THIS WATER.
THE CITY OF PANAMA AND THE CITY OF COLON
TAKE WATER FROM GATUN LAKE FOR DRINKING WATER,
SO IT'S OF PRIMAL IMPORTANCE
NOT ONLY FOR THE TRANSIT OF THE VESSELS,
BUT ALSO FOR THE WATER CONSUMPTION OF THE CITIES.
Narrator: SO HOW DO YOU OPERATE A CANAL OF EPIC PROPORTIONS
AND STILL CONSERVE WATER?
TO ACHIEVE THE IMPOSSIBLE,
ENGINEERS MUST LOOK TO THE TRAILBLAZERS OF THE PAST.
Narrator: THE PANAMA CANAL EXPANSION PROJECT
IS ONE OF THE BIGGEST WATER GATEWAYS IN THE WORLD.
BUT TO OPERATE THIS GARGANTUAN CANAL AND STILL CONSERVE WATER,
ENGINEERS MUST LOOK TO THE PAST.
THEY FIND INSPIRATION
IN ROMAN EMPEROR CONSTANTINE THE GREAT,
WHO COMMISSIONED AN ENGINEERING WONDER
WHEN HE RELOCATED THE EMPIRE'S CAPITAL
FROM ROME TO WHAT'S NOW ISTANBUL.
TO MAKE WAY FOR AN IMPERIAL CITY, ROMAN ENGINEERS
NEEDED A MASSIVE WATER-STORAGE SYSTEM.
Dr. Sheehy: THIS IS THE BASILICA CISTERN,
AND IT'S A STUNNING EXAMPLE
OF ROMAN HYDRAULIC ENGINEERING.
IT'S 140 METERS LONG BY 70 METERS WIDE,
AND THERE'S MORE THAN 300 MARBLE COLUMNS
HOLDING THE ROOF 9 METERS ABOVE THE FLOOR.
IT CAN HOLD ABOUT 80 MILLION LITERS OF WATER,
AND WHEN IT WAS IN USE,
THIS WHOLE SPACE WOULD HAVE BEEN FULL.
Narrator: AND A SPRAWLING NETWORK OF CHANNELS AND AQUEDUCTS
DELIVERED MASSIVE AMOUNTS OF WATER TO THE BASILICA CISTERN
USING NOTHING MORE THAN GRAVITY.
WITHOUT THOSE ENGINEERS,
THIS CITY WOULD NEVER HAVE BEEN THE SUCCESS THAT IT WAS.
Narrator: TODAY, THE PANAMA CANAL'S ENGINEERING TEAM
IS A GRAVITY-FED WATER-HOLDING TANK
TO RECYCLE THE WATER.
AS THE LOCK EMPTIES,
THE WATER CHANNELS INTO THE HIGHEST POND,
THEN THE MIDDLE ONE, AND FINALLY THE LOWEST ONE.
ONCE THE WATER IS IN THE LOWEST PART OF THE LOCK,
IT'S DUMPED INTO THE ADJACENT LOCK.
TO REFILL THE LOCK,
THE LOWEST HOLDING BASIN DRAINS FIRST,
FOLLOWED BY THE MIDDLE ONE AND THEN THE HIGHEST.
LIKE THE BASILICA'S CISTERN,
THIS SYSTEM RELIES ON AN ELABORATE VALVE SYSTEM
AND NOTHING MORE THAN GRAVITY.
Ferreira: WE'RE SAVING 60% OF WATER,
AND THAT IS A LOT OF WATER. AND WE'VE DONE IT.
IT'S WORKING WITHOUT ANY PROBLEM.
Narrator: BY WORKING THROUGH THESE CHALLENGES,
THE PANAMA CANAL EXPANSION PROJECT IS MAKING HISTORY
AS ONE OF THE WORLD'S MOST MASSIVE GATEWAYS.
AND OPENING UP A 2-MILE-LONG GATEWAY OVER THE WATER...
A BIG PART OF THE CONSTRUCTION, IT'S UNDERWATER.
Narrator: ...IS THE LONGEST FULLY SUSPENDED
CABLE-STAYED BRIDGE ON THE PLANET.
FOR CENTURIES,
BUILDING A BRIDGE ACROSS THE GULF OF CORINTH IN GREECE
WAS JUST A PIPE DREAM
DUE TO ONE SIGNIFICANT AND SEEMINGLY IMPOSSIBLE CHALLENGE.
BUT DESPITE THIS OBVIOUS HAZARD,
THERE IS DESPERATE NEED FOR A SAFE, RELIABLE CROSSING.
SO IN THE 1990s, CHIEF ENGINEER PANAGIOTIS PAPANIKOLAS EMBARKS
ON DESIGNING THE AMBITIOUS RION-ANTIRION BRIDGE.
HIS FIRST CHALLENGE IS TO DESIGN A BRIDGE
THAT COULD SPAN
THE ALMOST 2-MILE GAP OVER THE GULF OF CORINTH.
BUT THE DISTANCE IS TOO GREAT FOR A SINGLE-SPAN BRIDGE,
SO ENGINEERS MUST BUILD SUPPORT TOWERS IN WATER
THAT'S OVER 200 FEET DEEP.
Papanikolas: NO MATTER WHAT TYPE OF BRIDGE WE WANTED TO SELECT,
WE COULD NOT ESCAPE THE DEPTH OF WATER.
Narrator: BUT BUILDING BRIDGE SUPPORTS IN WATERS THIS DEEP
WOULD HAVE BEEN IMPOSSIBLE
WITHOUT THE GREAT INNOVATORS OF THE PAST.
THE TEAM TAKES THEIR CUE FROM BRITISH ENGINEER GUY MAUNSELL
WHO FIRST OVERCAME
THE EXTREME CHALLENGES OF BUILDING AT SEA
IN THE 1940s.
MAUNSELL'S INFLUENCE ON CONTEMPORARY ENGINEERING
I DON'T THINK REALLY CAN BE OVERSTATED.
THIS WAS REALLY THE FIRST TIME
THAT THIS HAD EVER BEEN ATTEMPTED,
AND SO IT WAS REALLY QUITE A DARING FEAT OF ENGINEERING.
Narrator: DURING THE SECOND WORLD WAR,
LONDON WAS A PRIME TARGET FOR GERMAN BOMBERS.
SO IN THE ENGLISH CHANNEL,
MAUNSELL DEVELOPED SOMETHING RADICAL -- NAVAL FORTS.
CONSISTING OF TWO 80-FOOT HIGH CONCRETE TOWERS,
EACH ONE CONTAINS FOUR FLOORS OF ACCOMMODATIONS
TOPPED WITH A GUN DECK.
BUT MAUNSELL'S TRUE INGENUITY LIES
IN HOW THESE TOWERS WERE CONSTRUCTED
AND DEPLOYED AT SEA.
Dr. Bisby: WHEN THEY HAD IT IN THE PLACE WHERE THEY WANTED IT,
THEY ESSENTIALLY JUST PULLED OUT A STOPCOCK AT ONE END
AND LET THE WATER FLOW IN.
AS THE WATER WAS FLOWING IN,
THE BARGE STARTED TO LIST IN THE WATER.
ALL 100 MEN WERE HANGING ON
AS THE FORT WAS SINKING AT 35 DEGREES.
Narrator: DESPITE A ROUGH SUBMERSION,
MAUNSELL'S GROUNDBREAKING DESIGN WORKED PERFECTLY.
THE BOTTOM OF THE BARGE BASICALLY FILLED UP WITH WATER,
AND EVENTUALLY THE ENTIRE BARGE SUNK TO THE BOTTOM
AND FLATTENED OUT.
Narrator: THESE GROUNDBREAKING NAVAL FORTS
HELPED BRITISH FORCES SHOOT DOWN
22 ENEMY AIRCRAFT AND 30 FLYING BOMBS.
THEY HELPED PROTECT LONDON FROM ATTACK
AND MADE ENGINEERING HISTORY.
Narrator: THE ENGINEERS OF THE RION-ANTIRION BRIDGE
ARE SUPER-SIZING
MAUNSELL'S REVOLUTIONARY FLOATING CONCRETE DESIGN.
BUT BEFORE THESE 80,000-TON FOOTINGS CAN BE TAKEN OUT
INTO THE GULF OF CORINTH,
ENGINEERS MUST FACE A MORE PRESSING PROBLEM.
THE GULF OF CORINTH LIES IN THE HEART
OF ONE OF THE MOST ACTIVE SEISMIC ZONES IN THE WORLD.
EARTHQUAKES CAN LIQUIFY THE SOFT SEAFLOOR,
WHICH WOULD CAUSE THE PIERS TO SINK AND THE BRIDGE TO COLLAPSE.
BUT THIS IS MUCH EASIER SAID THAN DONE.
TO MAKE THE BRIDGE EARTHQUAKE-PROOF,
ENGINEERS MUST MAKE THE IMPOSSIBLE POSSIBLE.
Narrator: THE RION-ANTIRION BRIDGE IN GREECE
IS THE LONGEST FULLY SUSPENDED CABLE-STAYED ON THE PLANET.
BUT THIS MASSIVE GATEWAY ACROSS THE GULF OF CORINTH
LIES IN EUROPE'S LARGEST EARTHQUAKE ZONE.
TO STABILIZE THE SEAFLOOR,
ENGINEERS DRIVE HUNDREDS OF PYLONS
DEEP INTO THE SOIL, WHERE THE FOUR PIERS WILL SIT.
BRIDGE FOOTINGS ARE USUALLY ANCHORED FIRMLY INTO THE GROUND.
BUT THE RION-ANTIRION ENGINEERS
PLACED THEM ON TOP OF A 10-FOOT LAYER OF GRAVEL.
THE LOOSENESS OF THE GRAVEL ALLOWS THE FOOTINGS
TO SWAY DURING AN EARTHQUAKE.
NOW BRACED FOR EARTHQUAKES,
ENGINEERS MANEUVER THE HALF-CONSTRUCTED PIERS
INTO PLACE FOR THE NEXT AUDACIOUS STEP.
EACH TIME WORKERS ADD A LAYER OF HEAVY CONCRETE,
THE PIER SINKS FURTHER DOWN,
INCHING IT CLOSER TO ITS FINAL RESTING PLACE
200 FEET BELOW ON THE SEAFLOOR.
THE END RESULT IS FOUR ENORMOUS HOLLOW FOUNDATION PIERS --
THE FIRST OF THEIR KIND.
BUT BUILDING A BRIDGE
ACROSS ONE OF THE BUSIEST TRADE ROUTES IN EUROPE
IS NO EASY TASK.
FOR THIS BRIDGE TO SPAN A 2-MILE GAP
WITHOUT INTERFERING WITH SHIPPING,
ENGINEERS MUST LOOK TO THE PAST.
IN 1826, BRITISH CIVIL ENGINEER THOMAS TELFORD
CHANGED THE BRIDGE GAME FOREVER
AT THE MENAI STRAIT,
WHICH SEPARATES MAINLAND WALES FROM THE ISLAND OF ANGLESEY.
CENTURIES AGO, BRIDGING IT WOULD HAVE BEEN IMPOSSIBLE
BECAUSE A TRADITIONAL ROMAN ARCH DESIGN BUILT INTO THE WATER
WOULD BLOCK THE PASSAGE OF SHIPS.
TELFORD REVOLUTIONIZED BRIDGE BUILDING
WITH THE MENAI SUSPENSION BRIDGE.
FOR A SUSPENSION BRIDGE, WE NEED TWO VERY STRONG ABUTMENTS,
AND THEN YOU NEED TWO TOWERS.
AND THEN WHAT YOU DO IS, ONCE YOU'VE BUILT YOUR TOWERS,
YOU TAKE A CABLE LIKE THESE GUYS,
AND YOU STRING THESE UP AND OVER THE TOWERS.
AND THEN YOU DROP HANGER CABLES DOWN FROM THE MAIN CABLES
AND THEN PUT YOUR BRIDGE DECK IN PLACE.
AND THEN ONCE YOUR BRIDGE IS COMPLETED,
IF YOU HAVE A LOAD THAT COMES ALONG -- SAY OUR CAR HERE --
IT COMES ALONG,
AND NOW WHEN THE LOAD GETS OUT NEAR THE MIDDLE OF THE SPAN,
THE LOAD FROM THE CAR THEN GETS TRANSFERRED UP
THROUGH THE HANGER CABLES
INTO THE MAIN CABLE UP OVER THE TOWER.
THE TENSION IN THAT CABLE
GETS ANCHORED IN THESE STRONG ABUTMENTS,
AND THE COMPRESSION FORCE HERE
GOES DOWN INTO THE FOUNDATIONS IN THE BEDROCK.
Narrator: TELFORD CREATED THE WORLD'S FIRST
MAJOR LONG-SPAN SUSPENSION BRIDGE.
ALL OF THE SUPPORT IS COMING FROM THE SUSPENDING CABLES
AND THE MAIN CABLES UP ABOVE YOU.
SO BELOW THE BRIDGE DECK,
THERE'S ABSOLUTELY NO OBSTRUCTIONS,
WHICH IN A STRAIT IS OBVIOUSLY A VERY IMPORTANT THING.
Narrator: THE RION-ANTIRION BRIDGE
IS SEVEN TIMES THE LENGTH.
BUT UNLIKE THE MAIN ANCHORED CABLES
OF TELFORD'S SUSPENSION BRIDGE,
THE RION-ANTIRION USES INDIVIDUAL CABLES
RADIATING FROM 4 HUGE PYLONS SPACED 1,600 FEET APART.
IN 2003, DECK BUILDING BEGINS.
EACH SECTION IS FLOATED OUT INTO THE GULF OF CORINTH
AND ATTACHED TO EITHER SIDE OF A PYLON UNTIL THE DECKS MEET.
THIS MASSIVE OPERATION TAKES OVER A YEAR TO COMPLETE.
BUT DESIGNERS MUST ALSO ENSURE
THE DECK CAN SURVIVE AN EARTHQUAKE,
WHICH REQUIRES A GROUNDBREAKING APPROACH.
INSTEAD OF RESTING FIRMLY ON THE FOUNDATION PIERS,
THE DECK HANGS A FEW FEET ABOVE THEM,
CREATING A FULLY SUSPENDED FLOATING DECK.
ENGINEERS HAD TO ENSURE RIGIDITY IN NORMAL CONDITIONS
BUT FLEXIBILITY IN THE EVENT OF AN EARTHQUAKE.
THEIR SOLUTION -- THE WORLD'S BIGGEST SHOCK ABSORBER.
THIS QUAKE-BUSTING DESIGN PROVES ITS WORTH
FOUR YEARS AFTER THE BRIDGE OPENS
WHEN A 6.4-SCALE EARTHQUAKE HIT THE RION-ANTIRION IN 2008.
THE INNOVATIVE DAMPENING SYSTEM KICKS INTO ACTION
AND SAVES THE BRIDGE FROM DISASTER.
BUT EARTHQUAKES AREN'T THE ONLY NATURAL FORCES
THAT THE ENGINEERS MUST OVERCOME.
TO BRACE THIS MASSIVE GATEWAY FROM NEAR-HURRICANE-LEVEL WINDS,
ENGINEERS MUST LEARN
FROM HISTORY'S ENGINEERING CATASTROPHES.
Narrator: SPANNING ACROSS THE GULF OF CORINTH IN GREECE,
THE RION-ANTIRION BRIDGE IS THE LONGEST FULLY SUSPENDED
CABLE-STAYED BRIDGE ON EARTH.
BUT TO CONSTRUCT THIS MASSIVE GATEWAY ACROSS A WIND TUNNEL
WITH NEAR-HURRICANE-LEVEL WINDS,
ENGINEERS MUST LEARN
FROM HISTORY'S GREAT ENGINEERING CATASTROPHES.
IN 1940, THE TACOMA NARROW SUSPENSION BRIDGE
NEAR SEATTLE EARNED THE NICKNAME "GALLOPING GERTIE."
JUST FOUR MONTHS AFTER OPENING,
THE BRIDGE'S TWISTING MOTION BECAME SO VIOLENT,
IT SUFFERED A CATASTROPHIC FAILURE.
AN INVESTIGATION FOUND
THAT 40-MILE-PER-HOUR WINDS
HITTING THE SOLID EDGES OF THE DECK
CREATED AN UNSTABLE OSCILLATION THAT FED OFF ITSELF,
CAUSING THE DISASTER.
WITH WINDS HERE REACHING 70 MILES PER HOUR,
ENGINEERS MUST MAKE THE BRIDGE DECK AERODYNAMIC.
AND LIKE THE FAIRINGS,
THE MASSIVE CABLES HOLDING UP THE DECK
MUST ALSO BE STRONG ENOUGH TO SURVIVE EXTREME WIND GUSTS.
SO HOW DO YOU MAKE NEARLY
40 MILES OF CABLES LIKE THESE WINDPROOF?
THIS WOULD HAVE BEEN IMPOSSIBLE
WITHOUT THE BREAKTHROUGH INNOVATORS OF THE PAST.
IN THE SECOND HALF OF THE 19th CENTURY,
GERMAN-BORN ENGINEER JOHN AUGUSTUS ROEBLING
DESIGNED HIS NEW YORK CITY MASTERPIECE --
THE BROOKLYN BRIDGE.
ROEBLING USED STEEL FOR THE BRIDGE'S
FOUR MASSIVE SUSPENSION CABLES BUT WITH A SIGNIFICANT TWIST.
AND AT COLUMBIA UNIVERSITY IN NEW YORK,
ENGINEERS ARE COMPARING THE CABLING SYSTEM
USED ON THE BROOKLYN BRIDGE
TO THOSE THAT CAME BEFORE IT USING A GIANT UNIVERSAL TESTER.
Brugger: THIS WOULD BE VERY SIMILAR
TO WHAT YOU WOULD HAVE ON AN OLD BRIDGE --
PRE-BROOKLYN BRIDGE FOR EXAMPLE.
Narrator: TO SIMULATE A BRIDGE FAILURE,
THIS STEEL BAR WILL BE STRETCHED UNDER MASSIVE TENSION.
SO, WE EXPECT THIS BAR TO FAIL AT AROUND A GOOD 200 TONS.
RIGHT NOW, YOU CAN SEE THAT THE NECKING
IS STARTING AT ABOUT A QUARTER UP FROM THE REDUCED SECTION.
THE ENERGY RELEASE WAS MASSIVE,
AND NOW THE SPECIMEN HAS JUST CATASTROPHICALLY FAILED.
IT'S BROKEN.
Narrator: NEXT, THE ENGINEERS TEST
ROEBLING'S STEEL CABLE DESIGN,
WHICH IS COMPRISED OF NUMEROUS, SMALLER WIRES.
AS THE GIANT UNIVERSAL TESTER STRETCHES IT,
THEY SUBJECT THE BOUND CABLE TO EXTREME HEAT TO WEAKEN IT.
YOU CAN SEE EACH WIRE IS ACTUALLY BREAKING
ONE AFTER ANOTHER.
IT'S NOT JUST THIS ONE CATASTROPHIC FAILURE
BUT RATHER THIS CASCADE.
Narrator: WHEN THE CABLE STARTS TO FAIL,
THE REMAINING WIRES TAKE UP THE LOAD,
DELAYING AN IMPENDING COLLAPSE.
SO, WHAT YOU SAW THERE WAS, YOU KNOW, EXACTLY WHY
THE SUSPENSION BRIDGE WIRES ARE SUCH A GREAT SOLUTION.
BUT YOU CAN SEE THAT YOU DIDN'T HAVE
THIS ONE CATASTROPHIC EXPLOSION AND JUST FAILURE OF THE MEMBER
BUT RATHER EACH ONE OF THESE WIRES ACTUALLY BROKE.
Narrator: BOUND WIRES LIKE THESE MADE OF STEEL
ENABLED JOHN ROEBLING TO DESIGN
WHAT WAS AT THE TIME THE WORLD'S LONGEST
AND STRONGEST BRIDGE.
180 FEET ABOVE THE GULF OF CORINTH,
CUTTING-EDGE SUSPENSION TECHNOLOGY
INSPIRED BY JOHN ROEBLING
KEEPS THE ULTRA-MODERN RION-ANTIRION BRIDGE
FROM CRASHING INTO THE WATER.
BUT UNLIKE NEW YORK CITY, NEAR-HURRICANE FORCE WINDS
IN THE GULF OF CORINTH
ALSO PUTTING A GREAT DEAL OF STRESS ON THE CABLES.
A WIND-TUNNEL FACILITY REVEALS
JUST HOW DESTRUCTIVE WIND CAN BE FOR A BRIDGE CABLE.
ALL RIGHT, SO, WE'RE GONNA START IT UP,
AND WE'LL SEE WHAT HAPPENS.
IF THIS WAS A CABLE IN A REAL BRIDGE,
THIS TYPE OF OSCILLATION
WOULD BE VERY WORRYING TO THE DESIGNERS
BECAUSE THAT CAN LEAD TO FATIGUE,
WHICH CAN CAUSE CRACKING
AND, HENCE, POTENTIALLY FAILURE OF THE STRUCTURE.
SO THE STRUCTURE COULD COLLAPSE
DUE TO OSCILLATIONS SUCH AS THIS.
Narrator: SO IN 1957,
BRITISH SCIENTIST CHRISTOPHER KIT SCRUTON
ADDED A SIMPLE FIN
TO REDUCE THESE CATASTROPHIC OSCILLATIONS.
HE CALLED THE FIN A HELICAL STRAKE.
Dr. Bisby: WITH THE HELICAL STRAKE,
WE GET THIS DISRUPTION OF THE FLOW PATTERN,
WE INTRODUCE SOME TURBULENCE,
AND BOTH THE FORMATION OF THE VORTICES
AND THE VIBRATION OF THE CABLE BOTH STOP.
THE HELICAL STRAKE SEEMS TO BE WORKING.
Narrator: HELICAL STRAKES ARE INTEGRATED
INTO ALL OF THE NEARLY 40 MILES OF CABLING
ON THE RION-ANTIRION BRIDGE.
THIS, COMBINED WITH SPOILER-LIKE DECK FAIRINGS,
MAKE THIS BRIDGE ONE OF THE SAFEST ON EARTH.
BUT IN THESE SPLENDID SURROUNDINGS,
A MASSIVE GATEWAY LIKE THIS CAN'T JUST BE FUNCTIONAL --
IT MUST ALSO BE BEAUTIFUL.
SO HOW DO YOU FIND THE RIGHT BALANCE
BETWEEN STRENGTH AND GRANDEUR?
DELIVERING BOTH WOULD HAVE BEEN IMPOSSIBLE
HAD IT NOT BEEN FOR A GREAT INNOVATION OF THE PAST.
Narrator: THE RION-ANTIRION BRIDGE IS A MASSIVE GATEWAY
THAT SPANS A RECORD-BREAKING 2 MILES
ACROSS THE GULF OF CORINTH IN GREECE.
BUT DESIGNING A BRIDGE THAT'S BOTH STRONG AND BEAUTIFUL
WOULD HAVE BEEN IMPOSSIBLE
WITHOUT ONE OF HISTORY'S GREAT INNOVATORS.
IN 1928, RENOWNED SWISS CIVIL ENGINEER ROBERT MAILLART
DESIGNED A GROUND-BREAKING BRIDGE
THAT LINKED TWO REMOTE MOUNTAIN TOWNS.
300 FEET ABOVE THE SALGINA VALLEY IN SWITZERLAND,
TOWERS THE AWESOME SALGINATOBEL BRIDGE.
FROM THIS LOCATION, WE HAVE A VERY NICE CLOSE-UP
NOBODY ELSE CAN HAVE.
MAILLART WAS A MASTER IN DESIGNING
SUCH SLENDER ELEMENTS, LIKE COLUMNS, LIKE ARCHES.
Narrator: CONCRETE IS STRONG IN COMPRESSION,
BUT REINFORCING IT WITH STEEL BARS
ALSO PROVIDES STRENGTH IN TENSION,
ALLOWING IT TO BE MANIPULATED INTO ALMOST ANY SHAPE.
WITH AN ELEGANT THREE-PINNED HOLLOW BOX ARCH
SUPPORTED BY REINFORCED CONCRETE COLUMNS,
THE SALGINATOBEL BRIDGE OPENED IN AUGUST 1930.
1,000 MILES AWAY IN GREECE, ENGINEERS ARE BRINGING
MAILLART'S AESTHETIC SENSIBILITY TO THE RION-ANTIRION BRIDGE.
THE FOUR REINFORCED CONCRETE PYLONS
EMBODY MINIMALISM, FLEXIBLE STRENGTH,
AND ELEGANT DESIGN.
Papanikolas: AS WE GO TOWARDS THE TOP,
WE TRY TO MAKE IT MORE ELEGANT.
AT DIFFERENT LOCATIONS OF THE BRIDGE,
YOU'LL FIND DIFFERENT TYPES AND DIFFERENT QUALITIES OF CONCRETE.
Narrator: 780,000 TONS OF REINFORCED CONCRETE
ALSO ENSURE THIS BRIDGE COULD SURVIVE AN EARTHQUAKE
OF 7 ON THE RICHTER SCALE.
FOR PANAGIOTIS PAPANIKOLAS,
THIS MASSIVE GATEWAY IS A LIFETIME ACHIEVEMENT.
Papanikolas: THIS THING LOOKS IMPOSSIBLE.
AND THEN AS LONG AS YOU KEEP WORKING
AND GET CLOSER AND CLOSER,
THEN YOU SEE YOU CAN BE CLOSE TO THE MILLIMETER,
AND THEY FIT TOGETHER.
Narrator: BY MODERNIZING INNOVATIONS OF THE PAST
AND MAKING GROUNDBREAKING DISCOVERIES OF THEIR OWN,
THE ENGINEERS OF THE PANAMA CANAL EXPANSION PROJECT
AND THE RION-ANTIRION BRIDGE
HAVE MADE THE WORLD'S MOST MASSIVE GATEWAYS.
THEY'VE SUCCEEDED IN MAKING THE IMPOSSIBLE POSSIBLE.