Load-Bearing Walls, Steel Skeleton, Skyscrapers and Otis Safety Elevator

Posted by PITHOCRATES - May 22nd, 2013

Technology 101

Because there is no Elevator in a Brownstone the Lower Floors are more Valuable

If you live in Manhattan on the Upper West Side you may have a view of the Hudson River.  Depending on how high you live.  For the higher you are the better your view.  Which is why the best apartments are on the top floors of our high rises.  Interestingly, though, if you live in a 5-story brownstone the prime real estate in those buildings are on the lower floors.  Why?  Because they don’t have an elevator.

Early buildings had a limit on height.  Because they had load-bearing walls.  And as the buildings grew taller the walls grew thicker.  To support the weight of the buildings above them.  Consider the pyramid.  Large, tall structures made of stone.  Part of the reason why they were pyramid shape was the weight of these heavy stones.  Supporting these heavy stones above the ground required a wide stone base below them.  So as a building got taller the walls got thicker on the lower floors.  So thick that they had less useable space than the upper floors.

It’s also more difficult to put windows in load-bearing walls.  As an opening reduces the strength of those walls.  In your typical 5-story walkup brownstone you’ll have small window openings facing the street.  Making it hard to flood these spaces with natural light.  So buildings with load-bearing walls have a few drawbacks.  Thick walls shrink living space.  And reduce the amount of natural lighting.  Not to mention having to hoof it up all of those steps.  Which is why the lower floors are more valuable in a brownstone.  For no one wants to walk up and down 5 flights of stairs every time you leave the apartment.

With a Steel Skeleton replacing Thick Load-Bearing Walls we can Enclose a Building with Glass Curtain Walls

In the 19th century new building technologies addressed these problems.  Thanks to Henry Bessemer and his Bessemer process.  The first cost-effective way to produce large amounts of steel.  Steel is stronger than iron.  But early steel was brittle.  Because of a high carbon content.  So we used iron.  For our train rails.  And our boilers.  But we could not harden iron as much as steel.  Because of a lack of carbon in iron.  Which is why iron boilers had a tendency to explode.  And iron rails failed.

Henry Bessemer changed that.  By blowing oxygen through the molten steel.  Which removed impurities.  And excess carbon.  Andrew Carnegie used the Bessemer process on a grand scale.  Producing the steel that built America.  Mass producing the structural steel that changed the way we built buildings.  Bringing the word ‘skyscraper’ into the lexicon of building.  As Carnegie’s steel sent our buildings soaring to the sky.

Instead of building thick load-bearing walls we built a rigid steel skeleton.  We anchored it to the earth with some steel-reinforced concrete piers deep underground.  And steel piles driven down to bedrock.  Giving us a tall, sturdy structure to build around.  The structure being so strong we can support up to a hundred (or more) concrete floors from it.  With useable space on every floor.  And without thick load-bearing walls we can hang glass curtain walls from this steel skeleton.  Wrapping the exterior of the building in glass.  Flooding these floors with natural light.

Before Elisha Otis and Andrew Carnegie the Top Floor of any Building was the Hardest to Let

So the steel skeleton allowed us to build buildings taller than ever.  But it took something else to allow those buildings to reach skyward.  For people were just not going to walk up and down a hundred flights of stairs every time they left their home or office.  They may walk up and down 5 flights of stairs in exchange for a cheaper rent in a brownstone on the Upper West Side.  But no one is going to walk up and down a hundred flights.  Even if they don’t have to pay rent.  So it was the elevator that really allowed today’s skyscraper.  Tiny little cars suspended by a few cables in a very long vertical shaft.

Elevator safety evolved over time.  At first it was not that uncommon for people to fall to their death in an elevator car that broke free from its cables.  Elisha Otis solved that problem.  He attached the elevator cable to a flat-leaf spring attached to the car.  The tension on the cable from the weight of the elevator car compressed the flat-leaf spring.  Drawing in mechanical linkages.  If the cable broke the energy in the compressed spring released and pushed down on the mechanical linkages.  Which forced arms outward and into saw-tooth safety rails that ran the length of the elevator shaft.  Bringing the elevator car to an immediate stop if the cable broke.

This revolutionized elevators.  And allowed our buildings to reach skyward.  As people no longer feared getting into an elevator.  Thanks to Elisha Otis.  Who went on to found the Otis Elevator Company.  If you see the word ‘Otis’ in the elevator car you’re in you can thank Elisha Otis.  For you’re in one of his elevators.  And you can thank Andrew Carnegie.  For giving us tall buildings.  And whose company may have even built the steel of the building you’re in.  Before Otis and Carnegie the top floor of any building was the hardest to let.  Because no one wanted to climb up all of those stairs.  But with tall steel and a safe elevator the top floor in a building now commands the highest rent.  Because of the view.  And the ease at which we could enjoy that view.



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Steam Locomotive, Diesel Electric Locomotive, Interstate Highway System, Airplane, Air Travel, Refined Petroleum Products and Pipelines

Posted by PITHOCRATES - March 21st, 2012

Technology 101

The Diesel Electric Locomotive could pull a Train Cross Country and into the Heart of a City with Minimal Pollution

The 1920s were transformative years.  The Roaring Twenties.  It’s when we moved from animal power to mechanical power.  From the horse and plow to the tractor.  From steam power to electric power.  From the telegraph to the telephone.  From the gas lamp to the electric light.  From crowded mass transit to the freedom of the automobile.  From manual labor to the assembly line. 

You can see a glimpse of that world in 1920’s Steam Train Journey Across the United States – Westward Ho!  The beginning of the modern city.  With modern street lighting.  Electric power and telephone overhead wiring.  Streets crowded with automobiles.  Tractors and mechanical harvesters on the farm.  And, of course, the steam locomotive.  Connecting distant cities.  Transferring the freight to feed the modern industrial economy.  And shipping the finished goods.  As well as all that food from the farm to our grocer’s shelves.  Proving the 1920s were vibrant economic times.  With real economic growth.  And not a speculative bubble.  For there was nothing speculative about all of this technology becoming a part of our way of life.

Of course the technology wasn’t perfect.  The coal-burning locomotives belched black smoke and ash wherever they went.  Which wasn’t all that bad in the open country where a train or two passed.  But it was pretty dangerous in tunnels.  Which had to be short lest they suffocated their passengers.  (One of the reasons why all subways use electric trains).  Making for some long and winding railroads in mountainous terrain.  To go around mountains instead of under them.  Slowing trains and increasing travel time.  And they were pretty unpleasant in the cities.  Where the several rail lines converged.  Bringing a lot of coal-burning locomotives together.  Creating a smoky haze in these cities.  And leaving a layer of ash everywhere.  The cleaner diesel-burning locomotives changed that.  The diesel electric locomotive could pull a train cross country and into the heart of a city with a minimal amount of pollution.  As long as they kept their engines from burning rich.  Which they would if they operated them with dirty air filters.  Reducing fuel efficiency by having the air-fuel mixture contain too much fuel.  And causing these engines to belch black smoke.  Similar to diesel trucks running with dirty air filters.

Airplanes can travel between Two Points in a Direct Line at Faster Speeds than a Train or Bus with Minimal Infrastructure

Trains shrunk our country.  Brought distant cities together.  Allowing people to visit anywhere in the continental United States.  And the railroads profited well from all of this travel.  Until two later developments.  One was the interstate highway system.  That transferred a lot of freight from the trains to trucks.  As well as people from trains to buses and cars.  And then air travel.  That transferred even more people from trains to airplanes.  This competition really weakening railroads’ profits.  And pretty much put an end to passenger rail.  For people used the interstate highway system for short trips.  And flew on the long ones.  Which was quicker.  And less expensive.  Primarily because airplanes flew over terrain that was costly to avoid.

Highways and railroads have to negotiate terrain.  They have to wind around obstacles.  Go up and down mountainous regions.  Cross rivers and valleys on bridges.  Travel under hilly terrain through tunnels.  And everywhere they go they have to travel on something built by man.  All the way from point A to point B.  Now trucks, buses and cars have an advantage here.  We subsidize highway travel with fuel taxes.  Trucking companies, bus lines and car owners didn’t have to build the road and infrastructure connecting point A to point B.  Like the railroads do.  The railroads had to supply that very extensive and very expensive infrastructure themselves.  Paid for by their freight rates and their passenger ticket sales.  And when there were less expensive alternatives it was difficult to sell your rates and fares at prices high enough to support that infrastructure.  Especially when that lower-priced alternative got you where you were going faster.  Like the airplane did.

Man had always wanted to fly.  Like a bird.  But no amount of flapping of man-made wings got anyone off the ground.  We’re too heavy and lacked the necessary breast muscles to flap anything fast enough.  Not to mention that if we could we didn’t have any means to stabilize ourselves in flight.  We don’t have a streamline body or tail feathers.  But then we learned we could create lift.  Not by flapping but my pushing a curved wing through the air.  As the air passes over this curved surface it creates lift.  Generate enough speed and you could lift quite a load with those wings.  Including people.  Cargo.  Engines.  And fuel.  Add in some control elements and we could stabilize this in flight.  A tail fin to prevent yawing (twisting left and right) from the direction of flight.  Like a weathercock turns to point in the direction of the wind.  And an elevator (small ‘wing’ at the tail of the plane) to control pitch (nose up and nose down).  Ailerons correct for rolling.  Or turn the plane by rolling.  By tipping the wings up or down to bank the airplane (to turn left the left aileron goes up and the right aileron goes down).  And using the elevator on the take-off roll to pitch the nose up to allow the plane to gain altitude.  And in flight it allows the plane to ascend or descend to different altitudes.  Put all of this together and it allows an airplane to travel between points A and B while avoiding all terrain.  In a direct line between these two points.  At a much faster speed than a train, bus or car can travel.  And the only infrastructure required for this are the airports at points A and B.  And the few en route air traffic controllers between points A and B. Which consisted of radar installations and dark rooms with people staring at monitors.  Communicating to the aircraft.  Helping them to negotiate the air highways without colliding into other aircraft.  And air travel took off, of course, in the 1920s.  The Roaring Twenties.  Those glorious transformative years.

Refined Petroleum Products have Large Concentrations of Energy and are the Only Fuel that allows Air Travel

The most expensive cost of flying is the fuel cost.  The costlier it is the costlier it is to fly.  Not so for the railroads.  Because their fuel costs aren’t the most expensive cost they have.  Maintaining their infrastructure is.  They can carry incredible loads cross country for a small price per unit weight.  Without swings in fuel prices eating into their profits.  Making them ideal to transfer very large and/or heavy loads over great distances.  Despite dealing with all the headaches of terrain.  For neither a plane nor a truck can carry the same volume a train can.  And heavier loads on a plane take far greater amounts of fuel.  This additional fuel itself adding a great amount of weight to the aircraft.  Thus limiting its flight distance.  Requiring refueling stops along the way.  Making it a very expensive way to transport heavy loads.  Which is why we ship coal on trains.  Not on planes.

Trains are profitable again.  But they’re not making their money moving people around.  Their money is in heavy freight.  Iron ore.  Coke.  And, of course, coal.  To feed the modern industrial economy.  Stuff too heavy for our paved roads.  And needed in such bulk that it would take caravans of trucks to carry what one train can carry.  But even trains can’t transport something in enough bulk to make it cost efficient.  Refined petroleum.  Gasoline.  Diesel.  And jet fuel.  For these we use pipelines.  From pipelines we load gas and diesel onto trucks and deliver it to your local gas station.  We run pipelines directly to the fuel racks in rail yards.   And run pipelines to our airports.  Where we pump jet fuel into onsite storage tanks in large fuel farms.  Which we then pump out in another set of pipelines to fueling hydrants located right at aircraft gates.

These refined petroleum products carry large concentrations of energy.  Are easy to transport in pipelines.  Are portable.  And are very convenient.  Planes and trains (as well as ships, busses and cars) can carry them.  Allowing them to travel great distances.  Something currently no renewable energy can do.  And doing without them would put an end to air travel.  Greatly increase the cost of rail transport (by electrifying ALL our tracks).  Or simply abandoning track we don’t electrify.  Making those far distant cities ever more distant.  And our traveling options far more limited than they were in the 1920s.  Turning the hands of time back about a hundred years.  Only we’ll have less.  And life will be less enjoyable.



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