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RE: Over-Engineering

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I Suspect Dr Brune would agree with the blowing sand theory and even have a time relationship with when a rock was more stable. I have seen balanced basalt rocks on top of mountains. There are many Engineers who are climbers, go ask one. Probably each condition will have its own time line and estimate of limits of seismic events. These records as a whole may lead to new understandings of the limits of larger seismic events in general.

It is responsible to consider a 10,000 year return period for a structure that is to harbor nuclear waste whose toxins can last twice that time period. A 10,000 year return period is used to represent a 1,000 year use. 20 times more than our building performance designs, but working stresses have a lesser increase (if any at all when using dampers and yielding members). I hope that in the next 50 years we will find a use for these waste products and an alternative source of power. If we could just consider the nuclear solution as a temporary bridge but design the containment for a future far beyond the economic interest.

Do you believe 2012 is the end? Others have concluded that, by 2012, if we do not change our ways then around 2050 we will have had to reduce our population to 30% of what it is today. We need to reach farther into the future than did our rational predecessors. This does not quite fit when sitting across the table from a client who needs an investment to survive a tax equation for obsolescence. Unanimous support of Global Warming keeps getting tripped up by short sighted views of weather events, ignoring the climate. Why is it temping to believe “the end is near” or “global warming isn’t happening”? Will it undermine your competitors? Does it let us spend more on our whims?

How does one sell the benefit of longer lasting structures?

Individual owners have a higher benefit when abating details that do not meet a 100 year return period seismic event. Seismic strengthening costs, at the 500 year return period, are usually most beneficial to the larger money interests who are using the community’s manpower and infrastructure. Neither person nor corporation seems to directly benefit from protection from a 1,000 year seismic event. The choice may have something to do with our society’s health needing to have a goal of a more distant future or just a simple and healthy concern for future generations.

Nuclear waste is more toxic than burning fossil fuels and it sticks around longer. The constant trend of human error for the next 1,000 years of using nuclear power could increase global background radiation to an inhospitable level. Nuclear energy is one front to fighting the warming climate. Global warming may not threaten our safety as a world population for another 100 years. I hope we will find a better energy source in the next ten years. I believe, to store nuclear waste, a seismic return period greater than what is used for common designs is reasonable. 10,000 years may be best.

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