Thursday, September 16

Tremors

An earthquake hit Manila around 3:10AM (+800 GMT). Sure brought me back to my senses. All it took was one small shove in the Manila Trench, and you've got all these massive forces unleashed on the Philippines. Among those unleashed was a small voice that said just how insignificant our little troubles are in the grand scheme of things.

Earthquakes tend to be worse than they actually are in buildings. Engineering-wise, it's because of a concept called sway. Ground movements are amplified by a certain factor, and I've been told that the higher you are on a particular building, the higher this factor is.

As a result, even the smallest of earthquakes has disastrous potential. However, that I feel earthquakes more strongly than the ordinary man on the street is not to say that sway is a bad thing. Engineers can usually set the sway frequency of a building during construction. Set your building to sway just right and you've got yourself a pretty earthquake-proof building. Remove sway totally, and the push-and-pull action the ground makes during an earthquake can level everything.

When we bought this unit in 1988, they told us that this was one of the most earthquake-proof buildings in the Philippines. Well, the support beams are among the thickest I've ever seen (the columns are more than a meter wide), but I have been told by some engineers have that this width is merely an illusion: most of the building's piping runs through these columns, considerably weakening the building's structural integrity. Chalk one up to falling for what legal people call "trader's talk". In other words, BS.

Just last year, people found cracks on the facade that ran from base to roof. No one can point, with authority, as to the cause of these cracks. Some have argued that these cracks are from a waterproofing problem encountered during the building's construction. My personal suspicion is that there is some flaw in the building that's developed over time. When your association dues are among the lowest in the Ortigas Central Business District, building maintenance probably isn't one of your strong suits.

The tremor itself wasn't so strong. However, it did last quite a bit. My wife suggested that perhaps it was time to head for the nearest door frame, and I'd wondered why the shaking hadn't stopped at least twice, all during the main quake.

I can't wait to move into my own home. Then I wouldn't have to worry about sway anymore. I also woudn't have to worry about a host of other things, but the earthquake's pretty much made those little things seem like a bonus.

On the plus side, David slept through the whole thing, and all by himself too. This is, I think, a first for David. In school, I'll bet those who woke up during the earthquake will talk all about it, and David will just look at them as if they were from Mars, eyes filled with blissful ignorance.

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