Quake proofing old house on stilts?

[Brian Sandle]

This is an over 80 year old house near the sea, so the nails will be getting a bit weak. It is built on stilts 5 to 7 feet tall, with mainly vertical outer covering for this `basement'. The basement has hardly any internal walls, except some flimsy rooms at one end. It has a few diagonal wooden steadiers at teh other end.

We do get some quakes here and once the steeple top was knocked off our

200 ft cathedral. Quite a bit of quake restance strengthening has been going on in big old buildings. New big ones tend to be built on rubber and lead `base isolators'?

A diagonal wooden strut will bend a bit under compression and allow some flexibilty one way, but will not stretch. I suppose quake forced oscillation will work with the strut straight as one maximum. Is it better to preserve some flexibility by having all the diagonal struts parallel?

The house has a brick chimney, too, and is on sand.

[Brian Sandle]

Yes, I was thinking of advances in thinking.

If I had wanted a large building before the days of base isolators being generally known an engineer would not have told me.

I read that houses supported on tall piles on hillsides are susceptible to earthquake damage?