Effective Stress - Part 2

This is physics as I love it - primal.  The most important formula of physics is F=ma.  Force is mass times acceleration.  For us, it is better to invert it a bit -- a=F/m  or zero acceleration means zero force.

Of course, nothing is simple since force and acceleration are vectors and everything must be summed.  This leads to the first study in engineering, that of statics and a force-balance diagram.  For, if you want something to stay still, like a building, you must balance all the forces.

You calculate it with a force-balance diagram, and if you want to learn anything here, go off and study it.  Then come back.  You couldn't believe the anguish in my Statics class.  Some people just couldn't get it, and had to drop out of engineering.  They went on to be seismologists and climate scientists.  :)

So, we'll start with a soil particle, a nice shiny grain of quartz, since I like quartz.  How does it live down there?

This grain does not live by himself.  He is squished by the other grains.  If he turned colour by the amount of squeezing, this would reflect the 'effective stress'.  There could come a point where the effective stress is very high, and he could crack.

There is one thing that could relieve him of some cracking pressure (stress), and that's water.  As I said in my Wikipedia explanation, we would have these quartz grains in a beaker, and fill it with water.  Those seismologists would do well to read this.  :)  They are bitching about the lack of references, but there's nothing!  Filling with water introduces some very interesting physics.

Effective Stress - Part 1

I am about to embark on a geotechnical lecture.  I am inspired by the Callie seismologists suddenly hauling out effective stress as the cause of the Oklahoma earthquakes.  They've never used water before!  But now they are misusing the poor thing, as it has always been misused.

Now, I'm off to do my research.

Making Canada more like Palo Alto

I wrote in my g+ that Palo Alto is a social nightmare.  It is a gated town, without actual gates.  The boundary road delineates a factor of 10 in property values, and a factor of 10 in quality of life.  Just crossing a few metres to get gas scares the hell out you in the daytime.

Inside this 'Reservation for the Rich', it's a paradise where rent per person (multi-shared) is $1000 a month.  All the locals vote down any proposal to increase the density, so it is probably the highest priced accommodation per square foot of actual land in the world.

Yet, it continues to generate the income to support this un-reality.  That's because there is a wild-west gold-rush fusion of money and brains.  You go to a party and you feel it.  Big money and big brains in the same breath.

So, how can the rest of world emulate this, without the road-crossing death scenes?

In Canada, we have bright technical people, but stupid money.  Palo Alto is full of Toronto engineers.  My son is starting a start-up.  Getting money thrown at him is the easiest part.  In Toronto, if you want to get a government grant you have to hook up with the local bagman-maffie person, and the thing needs a photo-op for ministers.  There is no hope.

I see some hope for devices, with Kickstarter, but this comes nowhere close to the PA brains-money fusion.