Showing posts with label stress skin panels. Show all posts
Showing posts with label stress skin panels. Show all posts

Monday, January 25, 2010

Haitian Fault






One thing about major active faults is that there are not too many of them. In fact they are rather uncommon and easily detected if you have your eyes open.  If faults are active, the ground bends and warps forming a scarred landscape.  It is easily recognized around LA or San Francisco.

There are also better hidden ones out in flat country that way more tricky to spot or well eroded old ones that sometimes come back to life.

However, the majority of quakes come from the same well known faults as we have just seen in Haiti.

The first problem is that people build along them.  This can not be properly avoided because a decent exclusion zone would be fifty miles to either side of the fault.  Yet San Francisco has shown that building codes can sharply curtail damage and death rates.

Their last quake was the same magnitude as the Haitian quake and their death toll was 68.  That starts been within an acceptable range for that level of disturbance.

The absolute key to it all are building codes that minimize the collapse threat.  That is what has killed possibly 200,000 in Haiti.  We see pictures of piles of concrete and almost no rebar.  Those buildings actually crumbled.

The first rule is to stop building unreinforced concrete structures at all.  Even better, adopt wood frame construction for housing up to three stories.  A quake will still tear them apart but they are fighting it all the way.  In Kyoto a few western build structure were noticeably still standing.

I can go further than that.  I can produce stress skinned panels that have perhaps half the weight and twice the strength for about the same end cost after construction.  It has not been made to happen yet, but it is feasible and is the future of global housing for that and superior energy retention and ease of construction.

Nothing is ever bullet proof but Haiti’s quake was survivable.  There was little ground damage suggesting foundations could survive.  Once the building is able to avoid collapse, the remaining threat is land movement and that is local and rare enough to ignore.

Haiti would be well served to switch totally to termite treated wood frame housing even if stress skin is not available. 

My point remains.  It is possible to build out a completely new Haiti using stress skin panel construction presently unavailable, at similar cost to other options, able to withstand a magnitude 7 quake and withstand a level 4 hurricane and possibly much more with negligible loss to human life.  A friend put several years of his life into perfecting the necessary art and I spent many months confirming and analyzing the economic model to an optimum solution.

Fault Responsible For Haiti Quake Slices Island's Topography

by Staff Writers  Washington DC (SPX) Jan 18, 2010



The sharp diagonal line exactly at the image center is the Enriquillo fault. Port-au-Prince is immediately to the left (north) at the mountain front and shoreline.


A magnitude 7.0 earthquake occurred on January 12, 2010, at Port-au-Prince, Haiti, with major impact to the region and its citizens. This perspective view of the pre-quake topography of the area clearly shows the fault that is apparently responsible for the earthquake as a prominent linear landform immediately adjacent to the city.



Elevation is color coded from dark green at low elevations to white at high elevations, and the topography is shaded with illumination from the left. The topography in this image is exaggerated by a factor of two.


The sharp diagonal line exactly at the image center is the Enriquillo fault. Port-au-Prince is immediately to the left (north) at the mountain front and shoreline.


The Enriquillo fault generally moves left-laterally (horizontally, with features across the fault shifting to the left when the fault breaks in an earthquake), but vertical movements occur along the fault where irregularities in the fault line cause local compression or extension of the earth.


Meanwhile, movements of the topography at the Earth's surface can falsely appear to be vertical where mountain slopes are cut and misaligned by horizontal shifts of the fault.


Additionally, differing erosion rates on the two sides of the fault, due to the juxtapositioning of differing rock types by the fault, can give the appearance of vertical offsets of the current topographic surface. All of these real and apparent horizontal and vertical offsets of the topographic surface may (and likely do) occur here, making the fault easily observed in the topographic data.


The elevation data used in this image were produced by the Shuttle RadarTopography Mission (SRTM), flown aboard Space Shuttle Endeavour in February 2000. SRTM acquired elevation measurements for nearly all of Earth's landmass between 60 degrees North and 56 degrees South latitudes.


For many areas of the world, SRTM data provide the first detailed three dimensional observation of landforms at regional scales.


The mission was a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DOD), and the German and Italian space agencies. It was managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA'sScience Mission Directorate, Washington, D.C.


View Width: One degree latitude (111 kilometers, or 69 miles)
View Distance: Five degrees longitude (525 kilometers, or 325 miles)
Location: 18 to 19 degrees North latitude, 70 to 75 degrees West longitude
Orientation: View east, 5 degrees below horizontal
SRTM Data Acquired: February 2000


Haiti Quake Occurred In Complex Active Seismic Region

by Staff Writers
Woods Hole MA (SPX) Jan 21, 2010


The magnitude 7.0 earthquake that triggered disastrous destruction and mounting death tolls in Haiti this week occurred in a highly complex tangle of tectonic faults near the intersection of the Caribbean and North American crustal plates, according to a quake expert at the Woods Hole Oceanographic Institution (WHOI) who has studied faults in the region and throughout the world.



Jian Lin, a WHOI senior scientist in geology and geophysics, said that even though the quake was "large but not huge," there were three factors that made it particularly devastating: First, it was centered just 10 miles southwest of the capital city, Port au Prince; second, the quake was shallow-only about 10-15 kilometers below the land's surface; third, and more importantly, many homes and buildings in the economically poor country were not built to withstand such a force and collapsed or crumbled.


All of these circumstances made the Jan. 12 earthquake a "worst-case scenario," Lin said. Preliminary estimates of the death toll ranged from thousands to hundreds of thousands. "It should be a wake-up call for the entire Caribbean," Lin said.


The quake struck on a 50-60-km stretch of the more than 500-km-long Enriquillo-Plantain Garden Fault, which runs generally east-west through Haiti, to the Dominican Republic to the east and Jamaica to the west.


It is a "strike-slip" fault, according to the U.S. Geological Survey, meaning the plates on either side of the fault line were sliding in opposite directions. In this case, the Caribbean Plate south of the fault line was sliding east and the smaller Gonvave Platelet north of the fault was sliding west.


But most of the time, the earth's plates do not slide smoothly past one another. They stick in one spot for perhaps years or hundreds of years, until enough pressure builds along the fault and the landmasses suddenly jerk forward to relieve the pressure, releasing massive amounts of energy throughout the surrounding area. A similar, more familiar, scenario exists along California's San Andreas Fault.


Such seismic areas "accumulate stresses all the time," says Lin, who has extensively studied a nearby, major fault , the Septentrional Fault, which runs east-west at the northern side of the Hispaniola island that makes up Haiti and Dominican Republic. In 1946, an 8.1 magnitude quake, more than 30 times more powerful than this week's quake, struck near the northeastern corner of the Hispaniola.


Compounding the problem, he says, is that in addition to the Caribbean and North American plates, , a wide zone between the two plates is made up of a patchwork of smaller "block" plates, or "platelets"-such as the Gonvave Platelet-that make it difficult to assess the forces in the region and how they interact with one another. "If you live in adjacent areas, such as the Dominican Republic, Jamaica and Puerto Rico, you are surrounded by faults."


Residents of such areas, Lin says, should focus on ways to save their lives and the lives of their families in the event of an earthquake. "The answer lies in basic earthquake education," he says.


Those who can afford it should strengthen the construction and stability of their houses and buildings, he says. But in a place like Haiti, where even the Presidential Palace suffered severe damage, there may be more realistic solutions.


Some residents of earthquake zones know that after the quake's faster, but smaller, primary, or "p" wave hits, there is usually a few-second-to-one-minute wait until a larger, more powerful surface, or "s" wave strikes, Lin says. P waves come first but have smaller amplitudes and are less destructive; S waves, though slower, are larger in amplitude and, hence, more destructive.


"At least make sure you build a strong table somewhere in your house and school," said Lin. When a quake comes, "duck quickly under that table."


Lin said the Haiti quake did not trigger an extreme ocean wave such as a Tsunami, partly because it was large but not huge and was centered under land rather than the sea.


The geologist says that aftershocks, some of them significant, can be expected in the coming days, weeks, months, years, "even tens of years." But now that the stress has been relieved along that 50-60-km portion of the Enriquillo-Plantain Garden Fault, Lin says this particular fault patch should not experience another quake of equal or greater magnitude for perhaps 100 years.


However, the other nine-tenths of that fault and the myriad networks of faults throughout the Caribbean are, definitely, "active."


"A lot of people," Lin says, "forget [earthquakes] quickly and do not take the words of geologists seriously. But if your house is close to an active fault, it is best that you do not forget where you live."


The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the 

Thursday, June 4, 2009

Living in Space

The primary source of space debris has been material losses from work done in space and explosively destroyed devices. The first is unavoidable under present protocols and the later is by choice. The point that I am making is that we are not actually living up there in a meaningful way and we already produce way too much junk.

The solution is a space operations protocol that makes it almost impossible for debris to get free in the first place. That can be done by adopting a spindle hub to a monofilament bubble that has a tire like cross section. The ‘tire wall’ can be very deep permitting a bubble diameter of even a kilometer or much more as experience and need determine. This initial component should be light and easy to deploy.

The spindle acts as the zero gravity work zone for docking and transshipment to the habitat. The bubble or ‘tire’ can be inflated with air and the system can be spun up to achieve a rotational velocity capable of providing artificial gravity at the outer perimeter and stabilizing the overall shape.

All further work takes place inside the bubble habitat and is accessed through the spindle. Thus any debris will be plausibly, after much improvement, be arrested at the outer shell wall.

Once set up, an easy next step is to strengthen the skin with internal small stronger patches that are laid down and edge attached, then inflated with polyurethane foam or some other space friendly foam that also acts as a binder. When this shell is set up and strengthened to handle possible penetration by debris it is a simple next step to attach hubs on the spindle able to carry cables able to hold bridges close to the shell and stacked inward as construction continues. In that manner to is possible to fabricate a space station with inertial gravity while doing the construction in a living atmosphere and capturing all debris as it comes free. The shell itself is easily reinforced to whatever strength levels deemed wise and also readily repaired with patching protocols when penetration occurs.

This design concept lends itself to safe operations and ease of fabrication. It can also be made supernaturally strong by the expedient of using superior suspension cables. And a station disc with a diameter of one kilometer and a thickness of a hundred meters could easily provide several million square meters of living and work space while continuously been designed and built out.

The skin methodology also lends itself to layering foil to lower radiation damage to the occupants. Protection from the more egregious forms is a bit more of a challenge but with an engineering design based on suspension it is plausible once resources are available from space.

Wednesday, July 9, 2008

UFO Enigma

Mankind is on the verge of achieving energy efficient spaceflight. And the only thing holding us up from complete mastery of the physical universe is a major omission in our understanding of mathematics. Most of what has been accomplished has been done in the two hundred years since we invented the steam engine. The rest is prelude.

Biological engineering can give us a very long life and allow us to prosper in space while completely avoiding the multiple hazards of Earth. It is all happening now.

My point is that this may have already happened. I have spoken of the harshness of ice age conditions, but that may be unfair. We had the tropics and we had huge coastal plains that would have been ocean moderated for much of the globe. This provided ample room for huge human populations to develop.

And then mankind leapt into space and was happy with the result. It was a simple step to properly reorient the crust ending the northern Ice Age and liberating the vast temperate land areas while giving up the coastal plains.

It was perfectly logical to allow the many surviving hunter gatherers to pick up the pieces and rebuild a new world. It has taken us 12,900 years and it is obvious that we did not break any records. Our understanding today is built on a finite set of mathematical tools and a ton of good empirical knowledge. For most of that history, we have resisted advancing that knowledge.

The only thing holding us back from moving into space is the need for an effortless one g thruster that allows a human habitat to prosper. The rest we have. Would you hesitate if it meant living for hundreds of years?

An extant space faring human population of billions living in our solar system would completely explain the much scorned UFO phenomena. It certainly removes the problem of motive. Now we know why they bother and why they do not communicate. There is no mystery for them. I would only be saddened if they did not experience compassion for us who live in the gravity well in ignorance of our options and potential lifespan.

Today we know what man can really accomplish, because we have done it. We had that exact same opportunity for fifty thousand years before the Pleistocene Nonconformity. Ask yourself, do you think that we did not do as much then?

Surprisingly, a close reading of the material that has come down through to us embedded in our cultural artifacts has tended to throw out conforming tales that fit just such a history. Or perhaps it is all shared wishful thinking.


It is a trivial matter to build an effective space habitation once man himself is modestly re engineered to prosper in the necessary environments. Everyone has heard of the Dyson sphere which is perhaps a step too far. I simply expect that we will simply inflate a balloon anchored to the ends of a central axis and spin it around the axis up to one gee at the equator. Cargo vessels can access at the axis end (zero gravity) and material may then be lowered to the equator. A suspended structure can be built from the equator inward, possibly occupying half to a third of the contained volume while maintaining useful gravity throughout. The outer wall can be readily thickened with additional balloon wall material and expansive foams that also bind forming stress skin panels. A structure with a radius of 2000 feet could house a million individuals all living with ample gravity.

Thousands could be built in the Asteroid belt and never be noticed. And an efficient outer surface of nano solar cells would be a black as coal.

I can do all this today with today's technology. I am only missing a cheap one gee thruster accessing limitless energy. Perhaps dear reader you will be inspired to invent such a device.