Archives: Living Bridges

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: if only our own infrastructure were as strong and natural as living bridges.


I've blogged a lot about bridges, I know (Sir Bridges Blog-a-Lot, eh?) but I haven't yet explored living bridges.

Meghalaya, a state in north-eastern India, is one of the wettest places in the world, getting close to 500 inches of rainfall a year. Almost three-quarters of the state is forested. One of the indigenous tribes living there, the War-Khasi, build living foot bridges from the roots of the Ficus elastica — a variety of rubber tree.

thebridgePhoto by Arshiya Urveeja Bose [CC BY 2.0], via Wikimedia Commons

To grow the bridges, the Khasis create root guidance systems out of halved and hollowed betel nut trunks. The roots are channeled to the other side of the river, where they are allowed to bury themselves in the soil on that side.

The bridges take 10 to 15 years to grow strong enough for regular use; once they do, they last incredible amounts of time with no maintenance: since they're still growing, they actually continue to grow stronger and stronger over time. Some of the older bridges are five centuries old. Many of the older, stronger bridges can support 50 or more people at once.

mfthought

Sometimes I think about crossing a bridge.

The most famous of the bridges, the Umshiang Double-Decker Root Bridge, is actually two of those bridges, with one stacked directly over the other. Local dedication to the art has kept the bridges alive and prevented them from being replaced with steel. (Steel, frankly—and with all respect to those dealing with, ahem, yard ramps—doesn't have anything near the lifespan of the root bridges and aren't nearly as sturdy.)

The root bridges aren't the only living bridges around. In the Iya Valley in Japan, there are bridges woven out of living wisteria vines. They're much less common, and only three remain. They're built by growing immense lengths of wisteria on each side of the river before weaving them together—a process that must be repeated once every three years.

These wisteria bridges are much less sturdy than the Khasi root bridges, with wooden planks spaced over seven inches apart, and they apparently shake wildly while you're on them. By all accounts, these things are terrifying to cross, which makes sense: they’re widely thought to have been designed originally for defense. The original bridges didn't even have railings.

Yard Ramp Guy Blog: Industrial Protection

This week my friend The Yard Ramp Guy makes a compelling case for worker safety.

Click HERE to peruse his perspective on proper planning.

Archives: Traffic Flow

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: zippers for roads? You betcha.


All traffic isn't created equal.

Zippy Traffic...via Zipper

For example, you've likely noticed that the morning rush hour often has greater traffic coming into the city from the suburbs and that the evening rush hour traffic clogs up the outbound lanes.

So, we tend to have traffic moving much more slowly in one direction than the other.

Accidents and our tendency to rubberneck them also cause the traffic to bunch in one direction. (Yes, we can keep listing these reasons for a while.) Unfortunately, building new lanes for our roadways can be prohibitively expensive, and it often isn't even possible, especially where bridges are concerned.

There is a fascinating solution, though:

Road zippers are heavy vehicles that have the ability to move concrete lane dividers across a lane, widening the road for one direction of traffic, narrowing it for the other. This requires a special type of moveable barrier, with shorter segments linked together by flexible steel connectors.

The road zipper, plus new barriers, are far, far cheaper than an entirely new lane. They actually pick up the segment lines using a little conveyor system, essentially acting on the same principles as a screw or a ramp (though Jeff Mann, The Yard Ramp Guy, might think I'm stretching that definition a bit).

Road zippers can move the lane at up to a top speed of 10 mph, depending on traffic, and is much safer than trying to manage traffic with cones and lights. They're especially useful on bridges. Crews on the Golden Gate Bridge have been employing a road zipper since 2010 to manage rush hour traffic, to great effect.

Any road crew that's worked on a bridge isn't going to have particularly fond memories of dealing with bridge traffic, and the road zipper provides an effective solution. We can also use this method to speed up bridge re-decking projects, moving the barrier to protect the work zone.

Transportation authorities utilize road zippers all around the world, and they're especially popular in the United States and Australia. Many cities use them on a permanent basis, while others lease them temporarily during construction work.

Even if they weren't so useful logistically, I'd still like them: they're just plain cool.

_________

Quotable

“If you don’t know where you are going, any road will get you there.”

— Lewis Carroll

Yard Ramp Guy Blog: Ramps for Material Handling

This week, my friend The Yard Ramp Guy shows us how yard ramps and strawberry Pop-Tarts are connected.

Click HERE to read about my new favorite connection.

Archives: Doing the Marengo

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: can limestone caves save the human race?


mcave

A kids' version of the man cave?

Marengo Cave is an enormous, beautiful natural cave in Indiana. It's easily traversable for tourists, isn't particularly muddy or wet, and is absolutely beautiful.

A group of children discovered the cave in 1883, and the townsfolk—immediately recognizing a potential tourist attraction—quickly declared it a protected site. A few years ago, Marengo Cave was declared a US National Landmark.

It's not the only cave in Marengo, Indiana, though.

The Marengo Warehouse is an old underground limestone quarry located just a few miles away from Marengo Cave. Opened in the 1800s, it contains almost four million square feet of storage space (more than 100 acres), about a quarter of which is in use. The owners converted it from a mine to a storage warehouse in response to competition from much larger limestone quarries.

All sorts of rumors swirl around the warehouse. For example, the Center for Disease Control supposedly stored supplies there for a long time, but the only actual government property inside are some 10 million MREs. The other contents of the warehouse include 400,000 tires and some 23 million pounds of frozen fruit, most of which are intended for use in yogurt.

The Marengo Warehouse is nowhere near unique. All around the world, we’ve converted limestone mines into storage spaces and business parks. This depends on how we mine the limestone. Since the 1950s, miners have worked carefully to ensure that the leftover space is actually useful, carefully removing 12-foot thick chunks of stone in grid-shaped patterns. When mining is completed, very little construction is needed to ready a cave for other purposes.

Me…in my man cave.

Me…in my man cave.

The underground limestone quarries are extremely stable. Limestone is made of compressed, ancient, tiny seashells. It's three times stronger than concrete, and has been used in construction for more than three thousand years.

Of course, there are certain concerns with use of the quarries. Ventilation is a much greater concern than in other mines, so electric forklifts are generally required instead of those powered by propane powered. And, while the older quarries are generally extremely stable, the geological strata above and below the facility must be monitored, to watch for shifting or cracking rock layers.

Now, I’m way too hopeful a man to get all bothered by doomsday scenarios, but if you really want to start preparing for all possibilities, those limestone caves might one day save the human race. I’ll stick to my man cave…when Maggie lets me, of course.

The Yard Ramp Guy Blog: Advanced Warehouse Planning

Just when I finished spring cleaning: this week, my friend The Yard Ramp Guy shows us the benefits of planning now for the end of the year.

Click HERE to watch him juggle.

Archives: Cable is the Real Web

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: Cable...is what's for dinner. And breakfast. And brunch. And lunch.


McCoy Fields underwater cables

Cable: The (wet) Connection

I've heard everyone—from my coworkers to the news outlets—describe ours as a wireless society. Nothing could be further from the truth.

A fun little statistic: In 2006, we transmitted less than one percent of all international data traffic via satellite. The percentage is a little higher today, but we continue to route the overwhelming majority of data through undersea fiber optic cables that stretch between every continent except Antarctica. Countries around the world consider them absolutely vital to their economies.

We've been laying underwater cable for a long time. Those first put into service were telegraphy cables, laid in the 1850s, though experimentation with the cables went back as far as the early 1840s (just a couple years after the invention of the telegraph). And during the Cold War, the United States and the Soviet Union tapped into and cut each others' cables.

Laying the cables today is immensely expensive. We spend billions of dollars each year on the process. And, while the cost has gone down a bit, it's still normal to see price tags hitting tens of thousands of dollars per mile.

Submarine cables also break, and they break frequently. Fishing trawlers, anchors, earthquakes, turbidity currents (giant underwater landslides), and shark bites are all major causes of these breakages. We're not entirely sure why sharks like biting them so much.

Repairing them is a difficult and costly process, involving specialized repair ships that lower grapples to lift the broken ends of the cables to the surface for repair. We employ different types of grapples, depending on the seafloor around the break (for example: rocky vs. sandy). In shallower waters, we can use submarines to repair the cables.

Politicians thrive on producing drama about literally anything. While drama over oil and such tend to hog most of the media attention, submarine cables are a really big deal.

The Yard Ramp Guy Blog: The Steel Surge

This week, my friend The Yard Ramp Guy explains how he manages to keep pricing comparatively low, even with the recent and "sudden" steel surge.

Click HERE to read another example of The Yard Ramp Guy's terrific reputation in the industry.

Archives: Raising a City

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: It turns out that buildings can be very moving experiences.


Stay with me on this one: yes, it begins on a pretty sour note…but I promise you there’s a happy ending.

Raise High the Roof Beams, Carpenters

Nineteenth century Chicago was plagued by, well, plagues. Epidemics of typhoid fever, dysentery, and cholera repeatedly hit the city. The 1854 cholera outbreak killed six percent of the entire city's population.

The reason for those diseases, and a common culprit throughout history: poor-to-nonexistent drainage. Standing water in a city makes a perfect breeding area for all sorts of nasty illness. In fact, disease historically was so bad that the majority of medieval cities experienced negative population growth—more people died of diseases than were born.

The only reason cities didn't depopulate was a near constant influx of immigration from the country. This changed steadily around the world when city infrastructure and medicine improved. Disease was still quite common in the 19th century, but Chicago's level of disease was quite unusual in an American city for the time.

In 1856, an engineer named Ellis S. Chesbrough developed a plan for a city-wide sewer system that would solve the problem. It was unusually ambitious: he wanted to raise the entire city six feet, then build sewers below the newly raised buildings.

Sounds insane, right? That's what I thought, too, except they actually did it—raising the first building in January 1858: a four-story, 70 foot long, 750-ton brick structure lifted on two hundred jackscrews to its new level, without the slightest damage. Engineers boosted more than 50 masonry buildings that year alone.

In 1860, a team of engineers actually managed to raise up half a city block in one go—an estimated 35,000 tons lifted nearly five feet into the air by 600 men using 6,000 jackscrews. They were so confident in the process that businesses didn't even close during the the five days it took to lift the whole thing.

On the last day of the process, before they began work on the new foundations, they allowed crowds to walk underneath the buildings, among the jacks. At another point, a six-story hotel was raised up without the guests even realizing it.

Only masonry buildings were considered worth raising; they placed wood-framed buildings on large rollers and moved them to the outskirts of town, usually without even bothering to empty out the furniture first.

This was so common that, for quite a few years, people considered looking out the window to see a building going past just another day of normal traffic.

The Yard Ramp Guy Blog: Angling Yard Ramp Strategy

This week, my friend The Yard Ramp Guy riffs on Yogi Berra's great quotation: "When you come to a fork in the road, take it."

Click HERE to see what direction The Yard Ramp Guy chose to take.