Bridge Design

I've been putting a lot of thought into what I want to specialize in during my time as an engineer. As my desire to be a structural engineer, there are many different opportunities I can venture into. I really have fallen in love with the idea of building and constructing bridges. There are many types of bridges for different purposes. 

Arch bridges are one of the oldest bridge types. Arches are good choices for crossing valleys and rivers because they do not need supporting piers in the middle. The design uses a curved structure to provide a high resistance to bending forces. When a load is placed on the deck of the bridge, the force is transported outwards horizontally towards the land on both sides. The bridge must be built on very solid ground. To add another perk, they can be one of the most beautiful types of bridges. 

A beam or "girder" bridge are the most simple type of bridges. In its basic form, it could be a log or a plank crossing a stream. The beam must be able to resist bending and twisting which will happen when a load is placed on the bridge deck. Modern examples use carefully designed beams to support the deck. Under load, the beams top section is compressed, while the bottom section is subjected to tension. The farther apart it supports, the weaker the beam becomes. The longest beam bridge may usually not exceed 250 feet. If a longer beam bridge is needed, many different bridges must be constructed and joined together, which we call a continuous span.

A suspension bridge works by hanging the deck of the bridge by flexible chains or ropes. Modern suspension bridges have two tall towers of which the cables are strung. Thus the towers are supporting most of the roadways weight. The force of compression pushes down on the bridges deck,  but since its suspended, it is transferred to the bridges towers, which dissipate the compression completely into the earth. The supporting cables are the receivers of the force of tension. They are literally stretched to support the weight of the bridge deck. There are two supporting anchorages on each side of the bridge to dissipate the tension that the bridge is receiving.

Of course these aren't all of the types of bridges, but they are the most widely used because of efficiency. These type of things really interest me for some odd reason, and no one else can understand. I suppose that is the reason I want to become an engineer. 

Licensure for Engineers

How do you actually become a legitimate engineer you may wonder? Each state and territory has there own specific requirements to be come officially licensed, but they all are very similar. It is usually a 4 step process including graduation, the Fundamental Engineering (FE) exam, work experience, and finally the Principles and Practices Engineering Exam. 

The first step is to graduate from a accredited engineering program from a college or university. Literally 99% of the colleges or universities in the United States are accredited to be acceptable. After the school work, a fundamental type exam is taken to ensure that proper background knowledge is present. This is called the Fundamental Engineering exam. It includes such subjects such as mathematics, problems and statistics, chemistry, economics, business ethics, computers, statics and dynamics, and strength of materials, material properties, fluid mechanics, thermodynamics, electricity, and magnetism. Phew, thats a mouthful, and you better be sure that you know everything I just mentioned before you take this exam. No one said being an engineer would be easy. After hopefully passing the test, you must aquire a certain amount of work experience.  This experience usually must contain close work with a licensed engineer(s). Also during the work experience, one must be subjected to work with increasing levels of responsibility. After you fulfill the certain work requirements, you are now ready to take the Principles and Practices of Engineering (PE) exam. This is where all of your hard work throughout the past 5-10 years will show. This is said to be one of the hardest "professionalism" tests in any career field. Knowledge of design, materials, natural forces, and unnatural forces will be tested extensively. There is only a 52% pass rate according to the National Council of Examiners. That is some serious business, so if your trying to be a PE, you better be well prepared.

Civil Engineering Salary

While recently researching all of these different types of engineering disciplines and sub-disciplines, I was very interested in the salaries engineers receive. I searched around the internet for a respectable website, and finally came to one called PayScale. I typed in Civil Engineering salaries, and literally almost fell out of my chair. "Starting salary- $49,000", you have got to be kidding. What I believe to be one of the most difficult if not the most difficult college programs one can be in, it is hard to believe that the starting salary is so low. Once one has graduated with an engineering degree, he is extremely proficient in mathematics, physics, and other sciences such as computer science and chemistry. decided to browse through the site and compare the starting salary for an engineer to other various careers. I found one that really made me upset, a senior pastor. They make on average $44,000 annually. How can someone who has no educational degree and speaks purely of their beliefs make almost as much money as one who has had extensive studies in some of the most difficult areas possible. It really boggles my mind. I think we deserve a bit more money. We design and construct the very structures and systems people rely on everyday. 

Different Sub- Categories of Engineering

After researching various civil engineering jobs, I realized that there were actually many sub-disciplines. I had no idea that civil engineering actually broke down into more disciplines. I thought civil engineers were mainly structural engineers, but I found out I was wrong. Some of them include structural engineering,  water resources engineering, environmental engineering, transportation engineering, construction engineering, geotechnical engineering, coastal engineering, and architectural engineering. 

Structural engineers plan and design houses, schools, and skyscrapers to resist powerful forces such as earthquakes, tornadoes, and hurricanes. Water resources engineers determine if water is safe, if its going to where its supposed to, and if their is enough. Environmental engineers research how new buildings and structures impact and influence the local water supply, animals and plants, and the air we breathe. Transportation  engineers research how people behave on the roads. Construction engineers arrange the processes used in constructing any structures. They must determine what material goes where, how it gets there, and why it goes there. A geotechnical engineer gather facts about the earth below a planned work site. They determine if it is a safe area to build. A coastal engineer monitors human activities and potential threats on shorelines around the world. Lastly, an architectural engineer ensures that the people inside a certain structure are comfortable and safe. They develop fire prevention systems, plumbing and water systems, air conditioning, and lighting. 

Engineering is a very broad spectrum. It breaks down into disciplines and then into sub disciplines. You can really narrow down your choices into practically anything you want to major your studies and works in.

New Jersey's Infrastructure

Fellow New Jersey citizens, I figured it would be important to assess the renovation our infrastructure needs all by it self. The top three concerns are roads, bridges, and mass transit. Well no kidding. If you live in New Jersey you know exactly what I'm talking about, but if you don't, let me explain. Each member of my family (mother, father, sister, myself) have cracked or bent at least 1 wheel on each of our cars from the road conditions. There are potholes wherever you seem to look, road unevenness, bumps, ditches, you name it. The roads are pathetic, and from my personal experience, can be devastating to your vehicle. Forget about having a low set car, and if you do expect to bottom out frequently. And having a low profile tire is idiotic, unless you plan on consciously avoiding everything you see. Bridges follow the same pattern as the roads, they look and drive like hell. Although I'm sure New Jersey isn't the only state with overcrowded roads and highways, it just seems that the problem would be fixed already. The people in charge of certain renovation projects drive on these roads and bridges everyday, and I can assure you they notice. 

Here are some interesting facts presented by the ASCE that will really make you feel safe in New Jersey:

"36% of New Jerseys' bridges are structurally deficient or functionally obsolete." That sounds promising." 

"There are 213 high hazard dams in New Jersey. A high hazard dam is defined as a dam whose failure would cause a loss of life and significant property damage."

"New Jersey ranked 12^th in the quantity of hazardous waste produced and 8^th in the total number of hazardous waste producers."

"78% of New Jersey’s major roads are in poor or mediocre condition."

There are many more where that came from. If you would like to visit the site and see how pathetic our country is becoming click.

America's Infrastructure

The ASCE (American Society of Civil Engineers) has recently put out a "report card" giving their overall grades for different aspects of American's Infrastructure. The society has researched the major structural categories Americans' deal with every day, and has given each a grade from A to F, respectively. The four main categories are Water and Environment, Transportation, Energy, and Public Facilities. Each of those categories were broken down into subcategories such as; dams, drinking water, hazardous waste, levees, solid waste, wastewater, aviation, bridges, rail, roads, transit, inland waterways, energy, public parks and recreation, and schools. Saying the grades are bad would be an understatement. In my opinion, the grades are hideous. No categories failed, thank the lord, but the following categories were given a D score (- or +); Aviation, Dams, Drinking Water, Energy, Hazardous Waste, Inland Waterways, Levees, Roads, Schools, Transit, and Wastewater. Eleven of fifteen categories received a score of a D. I have no words to explain why this is, but this is utterly pathetic. The following four categories received a score of C (+ or -); Bridges, Public Parks and Recreation, Rail, and Solid Waste. This is completely embarrassing. America is the Nation who is supposedly ahead of everyone else in every way, shape, or form. Yet we managed to receive a D for our cumulative score on our infrastructure. The ASCE estimated that over a five year period, we would need access to about 2.2 trillion dollars if we want to rightfully fix this problem. The largest portion of money would need to go to roads and bridges, an estimated 549 billion dollars. We really need to start worrying more about this issue, because our infrastructure is very important in the function of everyday life. It is also scary that our drinking water received a grade of D-. Since water is vital for everyday life, should we really settle for drinking water that is below average?

Narrowing It Down

There are many different types of engineers; civil, mechanical, chemical, environmental, agricultural, aerospace, and biochemical, to name a few. I have chosen to be a civil engineer, due to my interest in structural aspects of buildings, bridges, and dams. Now to be a civil engineer, you must narrow down the field in which you wish to have an expertise in. I have interest in buildings, but that field is very crowded with work. That is the career choice of many upcoming engineers, and I figure that there will not be many available jobs due to the popularity. So I thought long and hard about what expertise would be most interesting and would deliver the most potential jobs. I read that many of the bridges that were built in the beginning of the century are due to be renovated and possibly rebuilt in the near future. I decided that bridges would be the desired expertise in my mind. There will most likely be big money in the future when many bridges are inspected and will be needing renovation. I am hoping to land a job possibly in NYC or another city with big business and a need for many bridges to be up kept. There are far less bridge experts than there are building experts, due to the liability factors an engineer must undertake within building a bridge.

Pre- Requisites

Before one comes an engineer, he/she must take on an unyielding schedule of math and science courses to complete a degree. I will delve into the difficult yet rewarding classes I am required to take. 

Like I said, the engineering discipline requires a very strong mathematical background. Since their are a lot of precise calculations involved in the field, this is necessary.  Calculus I, Calculus II, Multivariate Calculus, Linear Algebra, and Differential Equations are all required courses for the Engineering major, and are to be taken in the order presented. The second most important series of classes one must take is physics. Engineering Graphics, Physics I, Physics II, Physics III, Dynamics, and Statics are all required for my field. The prior classes I have listed are required for all engineering majors, but there are a few specific courses I must take in order to fulfill the requirements for the Civil Engineering major. Physical Geology and Strength of Materials are both required for Civil Engineering major. 

Along with these classes, I must complete some ridiculous courses for a reason unknown to me. I must complete an economics class, god only knows why. I must also complete two physical education classes. The most idiotic requirement I must fulfill is to take four performing arts classes, including; theatre, orchestra, choir. Come on now, talk about a waste of money. Am I going to sing to my computer to have my design plans appear on CAD? Or maybe I'll dance on top of the keyboard.

Engineering Schools

We can talk about famous engineers, acts of invention, unthinkable structures, and new design all we want. But unfortunately, we need to do some studying to get to this point. Since my current residence at East Stroudsburg University only offers a pre-engineering major, I've been looking into some respectable schools around the area that I may consider transferring to. While I was surfing the Internet about this topic, I wondered, "If I had unlimited financial capabilities and a 4.0 GPA, where would I go to school?” So I proceeded to type into the Google search bar, "best engineering schools in the USA". I immediately looked for a reliable website and shortly after found www.usnews.com. They rated the top engineering schools in the USA from 1-10 in this order: Massachusetts Institute of Technology (no surprise there), Stanford University, University of California- Berkeley, California Institute of Technology, Georgia Institute of Technology, University of Illinois, University of Michigan, Cornell University, Carnegie- Mellon, and last but certainly not least, Purdue University. It shocked me that one of the top ten engineering institutes in America is only about 4 hours away from here. Carnegie- Melon is a prestigious university with much respect. Hey who knows, with the right amount of money, you can go to school wherever you’d like. 

WTC- Some Engineering Aspects

Height- 1,368 and 1,362

Owners- Port Authority of New York and New Jersey

Architect- Minoru Yamasaki, Emery Roth and sons consulting

Engineer- John Skilling and Leslie Robertson of Worthington, Skilling, Helle, and Jackson

Ground Breaking- August 5, 1966

Opened- 1970-73; April 4, 1973 ribbon cutting

Destroyed- September 11, 2001

Faced with difficulties of building to unthinkable heights, Yamasaki and engineers innovated a unique design: a rigid "hollow tube" of closely spaced steel columns with floor trusses extending across to a central core. "The columns, finished with a silver-colored aluminum alloy, were 18 3/4" wide and set only 22" apart, making the towers appear from afar to have no windows at all."(http://www.skyscraper.org/) Another unique aspect about the design of the buildings was that they were the first buildings of this size built without any masonry. Engineers used a drywall system fixed to the reinforced steel core. "The floor construction is of prefabricated trussed steel, only 33 inches in depth, that spans the full 60 feet to the core, and also acts as a diaphragm to stiffen the outside wall against lateral buckling forces from wind-load pressures."(http://www.greatbuildings.com/)

Do you beleive the World Trade Center was taken down by controlled demolition?

On a recent survey taken by over 1,000 people on RichardDawkins.net, the majority of the voters (61%) claimed to beleive that "No, things happened pretty much the way the mainstream media presents it (even if the Bushies are evil enough to conceivably do something that harmful, no one could have pulled that big a job off without being caught)." This did not surprise me, since I believe most of the American population believe what they see on the news and other television programs. Though it us upsetting to think that American's can be brainwashed by a simple news anchor telling a story which is edited and "lightened up" for the masses. I concur that mostly everything we hear in the newspaper and on the news is edited to be more pleasing for us to hear, and we are left in the dark about a lot of details. The second highest percentage of voters (16%) voted "No, but the Bushies might have left the barn door open. I'm not sure." This site may be completely democratic, but with all variables constant this shows that American's believe that the last presidential party was very deceitful and secretive. Upsetting to think that most of the majority of voters think that the World Trade Center wasn't taken down by controlled demolition, but yet have little trust in the presidential party? Very odd if you ask me. The third highest percentage of voters (13%) agreed upon "Yes, and there's plenty of evidence for it, damn it." I believe this group of voters are the people who have read and researched about the conspiracies and see pliable evidence. I didn't expect this group to be very large because of the time needed to research this matter, but I'm glad people care and aren't brainwashed by whatever the government says. The lowest percentage of voters (5%) agreed on No, and I'm offended that you'd say such a thing about the US's fine administration. We ought to lock you up in Gitmo for suggesting it." These are the "die hard" American's who believe the United States is the most loyal,honest, trustworthy country on this Earth. I have nothing to say to that.

Debunking 9/11 Myths

The magazine/website Popular Mechanics, has investigated 15 of the top World Trade Center Conspiracies with a group of over 100 researchers and reporters. They were apparently able to "debunk" every single theory with "hard evidence and a healthy dose of common sense." One of the most talked about theories the site talks about is how North American Air Defense Command (NORAD) did not intercept the off-route planes before they struck their targets. Over the years NORAD has intercepted hundreds of planes and have successfully investigated their purpose or problem. The Air Traffic Control monitors the radar signals of all passenger flights in Northern America. They are the transponders of information to NORAD. Yet on this day, no planes were even within hundreds of miles of all three hijacked planes. Conspiracists believe that the government had ordered NORAD to stand down, assuming that the government had an involvement in the attacks. Popular mechanics said, "Why couldn't ATC find the hijacked flights? When the hijackers turned off the planes' transponders, which broadcast identifying signals, ATC had to search 4500 identical radar blips crisscrossing some of the country's busiest air corridors." Now this may make sense, but with common sense in mind, why would an airline company install a switch to turn off a transponder. Absurd in my opinion. Second of all, is their any proof that the transponder was actually de-activated? There are loopholes in all stories stated. My point is that no-one can quote to have "solved the issue" or "cracked the case". Anyone can find a loophole in anyone's story. 

"World Trade Center Report Puts 9/11 Conspiracy To Rest"

On September 15, 2008 the National Institute for Standards and Technology (NIST) realeased the long awaited report on the collapse of WTC 7. Pat Dollard says, "Today’s report confirms that a fire was, indeed, the cause." I do not agree. “Our take-home message today is that the reason for the collapse of World Trade Center 7 is no longer a mystery,” NIST lead investigator Shyam Sunder told journalists at this morning’s press conference in Gaithersburg, Md. “WTC 7 collapsed because of fires fueled by office furnishings. It did not collapse from explosives or from diesel fuel fires.” I can't personally beleive this. I think that there were no other alternative conclusions for the cause of the collapse and the NIST left this resource as a last resort. Assumingly, every other office building that had caught fire in the history had to have had some sort of office furnishings in it. But these buildings did not collapse nearly within the same time frame as WTC 7. I'm not deeming this an impossibility, but it just seems very far fetched. In the case of WTC 7, there just seem to be too many first case scenarios that had happened. In any case, there could be thousands of possible scenarios that could cause anything. The unknown is infinite. But these were all researched after the fact that the building was fallen. Noone can prove a pinpoint reason why or how the building fell, but to conclude that burning office furnishings caused the building to fall is absoloutly rediculous to me.

ted.com for engineers

We engineers these days need somewhere to get new ideas. One of the greatest sources one can utilize is the internet. While surfing the internet, one of the main sites I usually browse is www.ted.com. The site has many great ideas presented by notable people about interesting engineering topics. I love the website for its scholarly videos presented at no charge. "TED speakers are asking the big questions and offering some big answers. Autodesk believes that many of today's big questions can be answered through innovative design." (www.ted.com) Autodesk is a CAD program widely used among the engineering field. Using this program, you can design and explain things once thought unimaginable. Autodesk actually sponsors the website, helping them display some of their finest projects.  For example: A designer uses Autodesk or one of the related programs to collaborate digital inventions, to share with a global team. This allows easier innovation and more efficient management. If you'd like to learn more, see this website and click on the fourth video.

What is the best CAD program?

Many detonators use 3-D computer images to achieve the most accurate demolition plan possible. There are hundreds of CAD programs available for this purpose, but which is the best? To name a few; Autodesk, AutoCAD, SolidWorks, KeyCreator, TurboCAD, and Revit. The Silicon Valley AutoCAD Power Users (SVAPU), which is the world's largest local AutoCAD user group, presented Revit with their "Best of the Best CAD Software" trophy. Revit was tested among many of the leading software programs, and was given the reward based on ease of use and a "nice intuitive feel". The program is mainly used for 3-D structural, mechanical, electrical and plumbling (MEP) engineering. I personally have only had experience with KeyCreator in my Engineering Design class. I found it to be simplistic enough for a first-time user, yet complicated enough for the professional. My professor who was PE described it as being "just as useful as AutoCAD minus all the confusion". I'm looking forward to exploring new programs in the near future.

The Big Bang

All the hard work has come down to this. The blasters must prepare the people in the area for the blast, assuring local authorities and neighboring businesses that the demolition won't seriously damage nearby structures. Once the structure had been pre-weakened and fully loaded with explosives, the crew does a final check to insure the explosives are ready, and the building and surrounding areas are completely clear. Blasters can calculate the safety perimeter from the size of the building and amount of explosives used. On occasion, blasters may have misjudged the amount of explosives needed to bring down the building. Too much, and debris fly farther than predicted, possibly injuring onlookers or nearby structures. Too little, the building does not completely fall down, making it an extremely dangerous environment. Once the area is clear, blasters retreat to their detonator controls and begin the countdown. 3...2...1... Typically, the implosion only takes a few seconds. After the building has fallen and the smoke has cleared, the team surveys the scene and reviews tapes to make sure everything went according to plan. It is crucial to make sure all explosives have detonated, and remove the ones that haven't. Most of the time, experienced blasters bring buildings down exactly as planned. Damage to nearby structures, is usually limited to a few broken windows. And if something doesn't work out quite right, the blasters log it in their mental bank and make sure it doesn't happen again. In this way, job by job, the science of implosion continues to evolve.

What does it take to demolish a building?

The first step to successfully demolish a building is to remove any debris within the structure. Next, destruction crews begin to knock down any non-load bearing walls. This allows for a cleaner break at each floor: if these walls were left in tact, it would stiffen the building, negatively effecting the collapse. They may also weaken supporting columns with sledgehammers or steel-cutters. Sounds fun so far. Next, blasters (explosives experts) start loading the buildings columns with explosives. Different explosives are used for different materials, and more or less of an explosive is used depending on the thickness of the material. The two materials typically dealt with are steel and concrete. Concrete is loaded with traditional dynamite or similar explosives. The dynamite does its job by completely disentigrating the concrete. Steel is a bit more complicated, because of its high density. It is loaded with cyclotrimethylenetrinitramine, RDX for short. Instead of disentegrating the column, it actually slices right through the steel, cutting it completely in half.To ignite both RDX and dynamite, you must apply a severe shock. In building demolition, blasters accomplish this with a blasting cap, a small amount of explosive material (called the primer charge) connected to some sort of fuse. To control the sequence, blasters typically configure the blast caps with some sort of delay mechanism. Blasters determine how much explosive material to use based largely on their own experience and the information provided by the architects and engineers who originally built the building. But most of the time, they won't rely on this data alone. To make sure they don't overload or under-load the support structure, the blasters perform a test blast on a few of the columns, which they wrap in a shield for safety. After they conclude what the proper explosive amount is, they wrap the columns in a shield to avoid flying debris from damaging near-by structures. Its almost that time.

How Building Implosions Work

Explosive demolition is the preferred way to bring down large structures. When a building is surrounded by other buildings, it may necessary to "implode" the building onto its footprint. Engineers in foreign countries were showed the video of the World Trade Centers collapsing with no knowledge of the 9/11 attacks. They all stated that they were convinced the buildings were intentionally demolished. Yet when they were eventually told the real story, they were shocked. The World Trade Centers demonstrated a picture perfect controlled demolition in the way they collapsed. Yet, the fires from the fuel of the planes are still stated to have caused the steel to collapse in the buildings. The basic idea of explosive demolition is quite simple: If you remove the support structure of a building at a certain point, the section of the building above that point will fall down onto the part of the building below that point. The explosives are just the starting point of the demolition, gravity actually brings the building down. Demolition teams load explosives at multiple levels of the building to ensure the structure falls down on itself on multiple points. When a building is surrounded by other structures that need be preserved, the demolition must be laid out carefully. The lower floors are detonated first, then a floor in the middle and top of the structure usually follow. For example in a 20 story building, the 1st and 2nd floor would be detonated first, then following this explosion the 12th and 18th might be detonated. This formula usually causes the building to collapse on itself. Note that right before the WTC collapsed, there was a large explosion on the 1st floor of the building. Makes you wonder huh?

The 9/11 Conspiracy

Multiple researchers have put together a very notable video presentation about the 9/11 attacks on the World Trade Centers and the Pentagon.  They argue in this video that the attacks were in some aspect related within the government. I'm not stating whether I believe it or not, but the researchers seemed to look very deeply into the matter and have put together quite a presentation. The main part of the video that caught my eye was the analysis of the actual falling of the two world trade buildings. When the buildings were engineered, they were built to withstand being struck by the biggest plane of that time, the Boeing 707, at a speed of up to 600 mph. The plane that struck the trade center was a Boeing 727, a smaller plane than the 707, and was only traveling around 450 mph. The "main cause" of the collapse was a widespread fire caused on multiple floors by falling debris. Oddly enough, the 3 World Trade buildings were the only steel frame buildings in history to ever completely collapse from a fire. Many other buildings of similar size in history have caught fire with the same severity, and burned 3x, 4x  longer, but strangely did not fall down. The final point I will argue with is that no building can collapse onto itself in the way the World Trade Center did without having been purposely done so. Many eyewitnesses said they heard a series of explosions seconds before the building collapsed. The main idea of this video is to point a finger at the government and saying they knew about the attacks and were possibly even involved. I'm not saying I do or do not believe in the theory, but the writers really have some good conclusions. I'd urge you to look at the video here.

The part about the World Trade Centers start at 54:42