It was in the wee hours of April 16th one year ago that the second big earthquake hit the Southwest region of my homeland. It was even bigger than the first – experts now say this was the main shock and the first was a foreshock, but back then, we were all shocked more by the fact that the earthquake got bigger with time.
It was not only the magnitude, but also the number, that defied our general belief from past experience that shakes will dwindle down incrementally. Even the most carefully calculated estimates by renowned scientists could not predict what was going on, or what will happen next. All they could tell us was that the worst may yet to come, and fear and panic quickly spread throughout the affected areas.
Upon dawn the following morning, we were devastated by what became apparent in sunlight… among the many many buildings that survived the harsh shakes of the first earthquake but could not stand those of the second was the landmark castle of the most affected area. Maybe the sight of collapsed stone walls and fallen roof tiles of the castle was what shocked us all the most.
One year later, I watched a documentary which followed the activities of the castle restoration team formed within the local municipal government. Their goal is unmistakable: to repair the castle erected over 400 years ago to keep it standing just as long, and longer. But the path to attaining this goal is still, by and large, a maze. They are still trying to figure out what can be salvaged and what must be rebuilt anew. And it is no different for the stone walls.
Through their hard work, it has been discovered that the architects of 400 years ago had already worked out a formula that would minimize the forces of earthquakes to keep the stone walls intact – rocks on the surface were piled perpendicular to the slope of the walls, rather than parallel to the ground, to dissipate the effects of horizontal shakes, and these rocks were larger than any others used in the walls to maximize the friction surface and therefore power to resist being thrown out of position!
Architectures of today are quite impressed with this formula. They say we are to thank this formula for the parts of the stone walls that survived both big earthquakes and stayed largely intact. They are convinced it is still an effective formula today, and theoretically, it can keep the walls intact well into the future. But over the past year, there are now places at which these intact walls have started to bulge out, and at least one has burst and led to an extensive collapse.
It is now understood that the formula could not realize its full potential due to a structural weakness within the walls. Deeper in, much smaller rocks are piled spatially, so as to act as cushioning when hit by earthquakes to absorb the shakes. This was a remarkable technique invented in a time when there were no shock-absorbing materials or structures we commonly see today. But after hundreds of aftershocks over the past year, they have snuggled up more tightly and stiffened, and now can exert enough force to push out the large surface rocks from within. It appeared to me that the once innovative technique was now very much outdated.
My personal opinion on the stone walls is, the formula stays, but the technique goes. Maybe we can have a small sample of the technique as historical reference where damages can be kept minimal, but I feel it is neither practical nor safe to rebuild using a technique that cannot meet the standards of today. Besides, it is used deep within the walls, where it cannot be seen, so I find no problem aesthetically… I actually think it would be kinda cool to have old-looking structures with state-of-the-art insides!
But, the restoration team never once (at least from what I could tell from the documentary) discussed this option. There are now at least nine places in the walls confirmed to have bulges, but they are still talking about how they can restore the walls using both the formula and the technique, though they understand the latter needs quite a bit of refining.
Maybe this is the most shock therapy they could give to our unwillingness to change how things are done.
But maybe time has come to give this mentality a shock therapy.
Maybe it is time we called for bolder measures to have more constructive talks within the reconstruction team.
Maybe the stone walls and the reconstruction team alike need to change from within.