The Coffee Break

  • The Coffee Break


Welcome to November’s issue of The Coffee Break!


This month, we take a brief trip to St. Louis, MO to look into the Gateway Arch designed by Eero Saarinen who also designed the Washington Dulles international airport and the John Deere headquarters in Illinois.

From there, we jump to this month’s big holiday. No, not Thanksgiving — Black Friday. When did this shopping tradition start and why is it really called Black Friday?

Lastly, a brief overview of a recent project we completed for a medical center and, of course, another brain teaser.
So sit back, enjoy, and thanks for your continued interest in our


Last month’s brain teaser:
“Bridge Crossing”
A group of four people has to cross a bridge. It is dark, and they have to light the path with a flashlight. No more than two people can cross the bridge simultaneously, and the group has only one flashlight. It takes different times for the people in the group to cross the bridge:
Roger crosses the bridge in 1 minute,
Crissy crosses the bridge in 2 minutes,
Stephen crosses the bridge in 5 minutes,
Anita crosses the bridge in 10 minutes.
How can the group cross the bridge in 17 minutes?
Roger & Crissy cross, 2 minutes
Crissy crosses back, 4 minutes total
Steve and Anita cross, 14 minutes total
Roger crosses back, 15 minutes total
Roger & Crissy cross, 17 minutes total


Brain Teaser


“International Intrigue”


If all the below statements are true:

1. Gianni was either in Italy or France in 2012.
2. If Gianni did not kill Versace, then Hilton must have killed him.
3. If Versace died of suffocation, then either Gianni killed him or Versace committed suicide.
4. If Gianni was in Italy in 2012, then Gianni did not kill Versace.
5. Versace died of suffocation, but he did not kill himself.


…who killed Versace and where was Gianni in 2012?


Answer to be posted in the next issue of The Coffee Break or email your answer to to find out if you have the solution.

Gateway to the West


The Gateway Arch1 300x191 The Coffee Break

The Gateway Arch ¹

In September of 1947, an architect by the name of Eero Saarinen and a structural engineer, Hannskarl Bandel, won an architectural competition to decide the design of a memorial commemorating Thomas Jefferson’s and St. Louis’ role in the westward expansion of the United States. The impressive Gateway to the West, or Gateway Arch, in the Jefferson National Expansion Memorial is the result of that competition.

The winning design was an inverted catenary arch. A catenary arch is similar to a parabola, but the loading is what differentiates them. With a parabola, the load is distributed evenly in a horizontal line like a suspension bridge. With a catenary arch, the loads are evenly distributed for the length of the chain. Simply put, a catenary arch is the curve created by a wire or chain from its own weight when supported at each end. With this type of curve the potential energy is minimized. Like a hanging chain that will naturally assume its normal position after a force is applied and removed. This means that the opposing forces, tension of the chain and the compression of the arch, are balanced providing stability.

Of course, the design of the Gateway Arch, with its 5,200 tons of steel and 38,000 tons of concrete, is a bit more complicated. Each leg of the arch starts 630 feet apart as an equilateral triangle 54 feet to a side. As the arch climbs, the triangles diminish in size to 17 feet to a side at the arch’s peak 630 feet in the air. The structure of the triangles consists of a 1/4″-thick stainless steel outer shell and a 3/8″-thick carbon steel inner shell starting with a 3-foot offset narrowing down to a 1-foot offset at the peak. Between the two shells, for 300 feet, the arch is filled with concrete. The arch is designed to sway 9 inches in either direction in 150 mph winds.

Nearing 50 years now since its completion, the Gateway to the West has withstood the test of time and still receives 2.5 to 3 million visitors a year. So next time you’re in Missouri, plan on stopping by and riding the tram inside the arch to the observation deck where you can appreciate the aesthetics of this national monument for yourself.

 The Real November Holiday


Frenzy at the Mall 200x300 The Coffee Break

Shopping Frenzy at the Mall ²

It’s almost here. Possibly the biggest unofficial holiday of the year: Black Friday. A day when stores open ridiculously early to kick off the holiday shopping frenzy. A day when people are already camped out equally early, to storm the stores for the best deals of the year. A great day for retailers and a great day for the consumer willing to brave the throngs of shoppers swarming the shops. But where did all this start?

To explain the answer to that, we have to go back in time a bit to the late 19th century and early 20th century when President Lincoln made Thanksgiving an official holiday in 1863. His proclamation didn’t really take effect until the 1870′s, after the country had rebuilt itself following the end of the Civil War in 1865. That’s when Thanksgiving Day parades started to appear, not evolved into the parades we are familiar today, but it was a start. Decades later, the more familiar store-sponsored parades began to appear like the Gimbels parade in 1920 and the Macy’s parade in 1924. (An interesting tidbit here about the first Macy’s parade; It was started by Macy’s employees and featured animals from the Central Park Zoo). So what does this have to do with Black Friday?

At the climax of the parade, when Santa appeared, it was considered the beginning of the holiday season by most and, through an unwritten agreement of sorts, it was when the retailers would begin their earnest pursuit of the holiday market. This unwritten agreement was actually so universally agreed upon by the retailers that in 1939, when Thanksgiving was going to fall on November 30th, the Retail Dry Goods Association warned President Franklin Roosevelt that sales would “tank” if they waited until the traditional start of the retail season. President Roosevelt’s solution: move Thanksgiving up a week.

Unfortunately, this didn’t really go over that well due to the October announcement of the move when many people had already made their plans for the holiday. The proposed Thanksgiving was quite derisively referred to as “Franksgiving.” Finally, the fervor calmed down and congress passed the 4th Thursday of November law that we are now familiar with. So why is it called Black Friday?

Many mistakenly believe the name comes from the retail stores getting into “the black” with their sales for the year. However, this was an attempt in the 1980′s to get away from the more negative origins of the moniker. The name “Black Friday” got its start in Philadelphia in the 1960′s. Black Friday falls right between Thanksgiving and the traditional Army-Navy game held in Philadelphia. Between the holiday and the hugely popular game the influx of people and traffic made navigating in Philly a nightmare for police, cab and bus drivers, and most anybody who had to travel the city so the police dubbed it Black Friday for how irritating it was. The name stuck and gradually spread throughout the nation and will likely carry the name for as long as there are shoppers willing to brave the traffic. (Personally, I’m just not that brave!)

Radiographic System Support Installation


Recently, one of our clients in the medical profession wanted to convert an existing vacant office into a Radiology room. In addition to removing and replacing the existing drywall, door and frame with lead-lined/backed materials, a new Radiographic system had to be installed. The travelling and telescopic system had to be rigidly supported overhead at the ceiling height, with a maximum allowable deflection of 1/16″ at any given point, and resist sway.

Typically, these systems are supported and braced from the rigid floors or roof structures above. In this case, the original roof trusses were spanning in excess of 50″- 0″, with potentials of 2-1/2″ of deflection, far exceeding the allowable amounts of the equipment’s parameters. The supporting arrangement for the equipment had to be completely independent of the roof trusses.

Additionally, the existing building column and exterior bearing wall locations, as well as the utilities above the ceilings prohibited the installation of any new support steel framing between the building columns or bearing walls, without major costs and disruptions to the entire medical offices operations.

In order to solve the problem we locally reinforced the existing office partition walls and designed the new steel beams to bear on the reinforced wall locations. We then installed Unistrut framing at the ceiling height, rigidly supported from the new steel beams and along the reinforced office walls. The equipment support rails, as well as the ceiling tile grid work, were then fastened to the Unistrut framing, resulting in an economical and stable installation with minimum disruption to the facility.

Questions or comments? E-mail us at or call 610.776.2042

1 Exothermic. “The Gateway Arch.” The Gateway Arch. May 31, 2009. November 11, 2012
2 Mooglet. “Crowding Malls.” Crowds. May 22, 2010. November 11 , 2012


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