Saturday, May 3, 2014

THE SOFT SIDE OF EARTHQUAKE PREPAREDNESS

While codes have continued to advance earthquake safe building, there are still a vast number of older buildings that fall far short of safe. Worst among them are the so called “soft” story buildings – the kind with the garage underneath and one side of the entire parking floor open to allow automobile access.

If you will remember the Northridge earthquake, these buildings came down like a stack of Jenga blocks, flattening cars and anything else underneath them. Insurance companies won’t insure them, which leaves owners open to huge law suits in the event that a quake does happen and renters are injured, or worse. While it may seem expensive to upgrade these properties, it’s nothing compared to what an owner stands to lose. It also makes the property insurable, more salable and more valuable. So there is every reason to upgrade now when the cost of this type of upgrade is lower than it’s been in years.

This is something we at Peter Erdelyi & Associates have been advocating for years and we will work with owners to structure a plan that makes it easy for them -- including doing the upgrade at cost with the balance paid with a post upgrade refi. If you own one of these buildings, or know of someone who does, please contact us.

Re-posted from our newsletter originally sent on 12/21/2012

SAVING MONEY ON A SAGGING FLOOR IN A SAGGING ECONOMY

Recently we were approached by a home owner whose hillside garage floor was sagging. The site visit revealed the floor members were still healthy, free of dry rot and termite, but that the previous owner had put a very heavy tile floor on top of the existing floor, causing the excessive deflection. Several contractors suggested the floor joists be replaced to the tune of about $30-$40K. Then it turned out that, in order to construct the floor, the walls of the garage had to be rebuilt. This was when the homeowner called Peter Erdelyi & Associates.

We saw there was room for a beam support under the garage floor joists that would spanning the length of the garage floor and supporting the posts and footings -- a simple and effective way reduce the deflection of the overstressed garage floor. Cost: $7,000.00

Now that is what we call "Value engineering"

P.S. Happy home owner, not so happy contractor.

Re-posted from our newsletter originally sent on 12/21/2012

WE HELPED SD AIRPORT EXPANSION TAKE OFF

The San Diego International Airport is celebrating the largest expansion in its 81-year history with the $1 billion "Green Build" Terminal Development Program. The project includes 10 new jet gates at Terminal 2 West, expanded dining and shopping, as well as terminal, roadway, parking and airfield improvements, as well as a new USO facility near Gate 19 in Terminal 2.

Peter Erdelyi & Associates, Inc. was part of an outstanding team working on the project. PE&A was assigned the structural analysis, design and detailing of a state-of-the art stay-in-place glazing structure. The steel structure supporting the glazing of the terminal “envelope” is designed and detailed to allow the main building to deform and reform during an earthquake event while the glazing structure stays essentially in place. It’s an amazing piece of engineering, with a very contemporary design of exposed steel tubes, bars and stainless steel rods connected together to form 3D trusses.

Re-posted from our newsletter originally sent on 12/21/2012

ON THE LIGHTER SIDE

Two engineers were standing at the base of a flagpole, looking at its top.

A woman walked by and asked what they were doing.

"We're supposed to find the height of this flagpole," said Sven, "but we don't have a ladder." The woman took a wrench from her purse, loosened a couple of bolts, and laid the pole down on the ground. Then she took a tape measure from her pocketbook, took a measurement, announced, "Twenty-one feet, six inches," and walked away.

One engineer shook his head and laughed, "A lot of good that does us. We ask for the height and she gives us the length!"

Re-posted from our newsletter originally sent on 8/6/2013

THE NEW SECOND UNIT - RENTAL OR PARENTAL

As everybody knows, there was always the possibility of building a "granny unit", or "recreation room" in addition to an existing single family dwelling on an R-1 zoned lot. These structures could not have a kitchen, because that would have created a "second unit". The City of Los Angeles recently changed the zoning to allow a second, or "rental", unit to be built on the same lot with a full kitchen and bathroom. It doesn't have to be just a wet bar and a half bath, as was the rule before. Parking requirements are very lax, only an open space has to be provided for this additional unit.

Easy isn't it?

We see a definite increase lately in these types of designs coming from the architects we do business with. It will be interesting to see what type of effect this will have on apartment building construction, which is in full swing lately.

Home owners, this is a great opportunity to create additional income to ease your mortgage payments or provide truly separate living quarters for your children returning from college, or aging parents. After all, nothing brings a family closer together than a little separation.

Love to hear from you...

Peter

Re-posted from our newsletter originally sent on 8/6/2013

THIS SHOULD BE OF INTEREST TO YOU

For all the mixed messages from the Fed and the uncertainty that has roiled financial markets recently, one thing looks very clear: The era of declining interest rates is over.

After three decades in which borrowing costs for Americans have pretty much declined steadily to rock bottom levels - easing consumer debt burdens for cars, homes, and college education - the long term path of interest rates is now at a turning point, according to many economist and investors.

Regardless of the Federal Reserve's statement recently and the market's reaction to Chairman Ben Bernanke's statements at his quarterly news conference, the reality is that the flood of easy money is ebbing and the economy is shifting to a new period of rising rates.

To some extent, the rising interest rates reflect the gradually improving American economy. Although still lackluster, the 4 year old recovery has settled into a fairly steady cruising speed, growing about 2% a year. Economic growth is widely expected to pick up toward the end of the year.

The benchmark 10-year U.S. Treasury bond yield was 1.66% in early May, but by the end of the month it had vaulted to 2.16% a huge jump. Mortgage rates, which are tied to 10-year Treasury yields, have crept up as well. Long-term interest rates peaked in the early 1980s with the 10-year Treasury yield averaging nearly 14% in 1981. It has fallen most years since then, to 7% in 1992, to 4.6% in 2002 and to 1.8% last year.

Analysts disagree over whether higher mortgage rates could wind up stalling growth. In the short term, it could push potential buyers into the market to lock in rates before they rise further. Longer range, the central question is, how the economy will be performing as rates climb back to historically normal levels.

If the economy is up, and people have jobs, and profitability is high, which is what happens when the economy starts to grow rapidly, no one is going to care, I think. What'd you think? I'd love to hear your point of view, as well!

Re-posted from our newsletter originally sent on 8/6/2013

IS SMALL THE NEXT BIG THING?

Are we going to follow our Japanese friends and say sayonara to larger living space? In the last few months more than one developer mentioned to me to be ready to design very small homes, the so called small-lot homes. It seems that after this economic, and real estate, downturn a substantial percentage of people are apprehensive about moving into so-called conventional size homes with larger mortgage commitments. Not just here in California, all across the USA. The "trend", especially for young urban professionals, is to get their own place, but near work and with low or no maintenance requirements, like big lawns and gardens.

So, many developers are designing and building new "small size" homes on tiny lots. The difference between these projects and actual condominiums is that there are no common areas, there is no annoying HOA's to deal with, everything is yours. It's a typical single family dwelling, but smaller.

This concept grew out of a 2005 Los Angeles City ordinance that aimed to add more affordable housing to the pool of housing starts in densely populated neighborhoods. This new ordinance cut the minimum size of lots for single family dwellings from 5,000 sq.ft. to 600 sq.ft. -- a substantial reduction.

Well, here at PE&A we've always said no project is too small.

What are your thoughts on this trend?

Re-posted from our newsletter originally sent on 8/6/2013

Friday, May 2, 2014

ANOTHER TAXING ELECTION!

I have long felt the most egregious and harmful tax to business in the City of Los Angeles is the tax on businesses gross receipts. Even if you have a loss for the year ( i.e: your expenses exceeded your income) you still have to pay a tax on the gross receipts of your business.

Ouch!

Who would have thought that two liberal Democrats - City Controller Wendy Gruel and Councilman Eric Garcetti- would both propose eliminating that tax! Cut taxes for business, Garcetti and Gruel contend, and the overall economy will grow, with benefits trickling down in the form of more jobs for Angelinos and more money in the city's general fund.

Kudos for them!

It's almost certain that one of these two contenders will win the upcoming runoff election for mayor, so it will be very interesting to see if this is one campaign promise that is kept. I'm sure all of you would agree, that this would be a real boost to businesses in Los Angeles.

Re-posted from our newsletter originally sent on 4/25/2013

GOING UP?

How many times have you encountered this typical LA situation: there's a beautiful lot, fantastic views, great location, but impossible to build on.

That was exactly the situation for an investor and his lot in the Hollywood Hills. The property had a stunning city view, it was adjacent to a beautiful lake, a fantastic location at an affordable asking price. It had it all.

So what was the problem?

The property was on the top of a steep slope, impossible to get to. To build at the street level wasn't an option, you lose the view. There were existing plans available for the street level construction, but nobody wanted to build at that level and miss that view. Building a drive way to the top was out of question because of the steep slope. The investor had already given up on the deal when the architect called us to the site to figure out some engineering solution. You know the old saying: If there is a will, and a good structural engineer, there is a way.

The solution? Build the garage at street level, then build a stairway on grade to get to and from the top on foot.

But who wants to walk up and down a slope that's the equivalent of six stories all the time?

Oh, well, in that case take the elevator. A six-story high one from street level. The one with a bridge to get to the house.

But what about the height restrictions of the hillside ordinance?

Simple. If you don't connect the elevator and the bridge to the main building of the house, you can be exempt of the very strict height limitations.

A little imagination gets another great project off the ground!

Re-posted from our newsletter originally sent on 4/25/2013

ANOTHER TALL STORY

What do you do if you want to build a three-story house, but the local planning only allows for a two-story?

That's the problem we faced when a local planning department determined the building we've been designing can't be taller than 33' with a sloped roof and 28' with a flat roof. The 28' height limit prohibited a third floor and a sloped roof on the top of the third floor would exceed the 33' height limit. What a conundrum! Everybody pretty much gave up on the third floor.

But where there is a will there is a way and we are very willing people here at PTE.

The answer: an accordion roof!

We created a motif of ridges and valleys slightly offset from one side of the building to the other side to achieve proper roof drainage, so the roof has the required 4:12 slope, but doesn't extend more than 3' above the plate line of the third floor, thus staying below the required 33' height limitation. A little more expensive, but the more dramatic design gave the owner the desired third floor and the planning department took lots of time to scratch their heads, but finally had to approve the concept!

Think of it as another crowning achievement of PTE.

Re-posted from our newsletter originally sent on 4/25/2013

ANOTHER CASE OF STREET SMARTS

Recently, our company was selected to do the structural engineering for a very unique single family compound -- four buildings on a lot with beautiful, sweeping views from downtown to the ocean, for a very famous Swiss sculptor/artist from Zurich. He just had a very big, successful exhibition in Los Angeles. I guess my German engineering background and knowledge of the language helped to get the job, as well. In addition to doing the structural engineering our company was asked to do civil engineering and expediting for the project, due to the fact that the architect is based in Zurich and our office is next to the Los Angeles Building and Safety's West side office on Sawtelle Blvd.

Part of the civil engineering was storm drain and sewer line design to discharge to the next public street. The problem was that the public street next to the property was a "paper street". You know the type of streets that exist on paper only, owned by the city. To run an 8" sewer line and an 18" storm drain line under this non-existent public street for about 200' to be connected to the existing lower street lines, with all the city drawing and permitting nightmares, would have cost the client 80-100K and months!

Here comes the thinking of a Hungarian civil engineer with LA street smarts.

If the sewer and storm drain go thru private land, sizes of drain and sewer lines decrease drastically, 8 to 6 and 18 to 8 inches respectively. We suggested to the owner to acquire a 3' easement of the neighboring lot for the purpose of running these lines on private property verses on public property. The neighboring property owner was agreeable to the idea, made some money on the deal and sold our client a 3' easement and the case was closed.

Construction saving: in the range of 50-60K

You know: where there is a will, and a good thinking engineer, there is a way...

Re-posted from our newsletter originally sent on 6/13/2013

LA IS BUBBLICIOUS!

The once in a lifetime mentality, fueled by a shortage of for-sale homes, is driving the Los Angeles area from recovery to frenzy, according to real estate agents, brokers, like my son, and experts. A report released recently by the real estate data and brokerage firm Redfin.com called Los Angeles of one the "bubbliest" housing markets in the U.S., second only to Washington, D.C.

The Redfin report comes as others have begun to raise concerns that housing might be approaching speculative territory. Professors Karl Case and Robert Schiller - creators of the widely followed home price index - have cautioned about fast rising home prices in recent months. Economists have also attributed much of the housing surge to investors' couple with the fact that banks are very slowly releasing REOs to maintain control of prices.

Many investors are buying homes to quickly sell again at a profit. Fixing and flipping is a robust business once again. We're going straight from Armageddon to speculation with no stops in between. That seems to be how the American economy works now, we just go from one bubble to the next and back again.

But there is a distinct difference between the home price run-up of the last decade and the current upswing. During the previous boom, listings abounded and sales soared. Now, rising prices are driven by a shortage of supply. And although underwriting standards may be relaxing, they remain tight when compared to when lenders did loans on stated income with no verification and issued enough subprime loans to crash the U.S. economy.

This is not a bubble by any stretch of the imagination. If you can't borrow, you can't speculate - that is the primary thing that will prevent this from happening.

What are your thoughts? Let me know.


Re-posted from our newsletter originally sent on 6/13/2013

EARTH SHAKING NEWS!

As all structural engineers know, one of the most dangerous and unsafe building types in California is the "Soft story" structures. As you know, soft story buildings are structures in which the ground level is parking with two or three floors of apartments above. Those who know me know this is a pet issue with me.

The buildings are, by design, "top heavy" and in the event of an adverse, strong ground motion the supporting weak, mostly wooden columns snap. The floors collapse on top of each other causing death and serious injuries for the people living in these types of units. We know this from the Northridge earthquake, where many of these buildings collapsed -- most notably the "Northridge Meadows" apartment complex where 16 people died in one building alone.

For years, at Building & Safety Departments in a variety of cities, I've championed passing an ordinance for a mandatory upgrade of these very unsafe and dangerous buildings to protect the public. It is too political, I was told, council members fear the backlash of apartment building owners, etc. There was only one city after the 1994 earthquake that passed a mandatory retrofitting program; Santa Monica in 1995. Now, another "progressive" city, San Francisco, has passed an ordinance for the same type of upgrade. And the vote was 11 to 0!

Kudos to San Francisco!

For the most part, retrofitting means additional bracing elements at the street level to make the buildings more rigid and able to withstand horizontal (earthquake) forces. It's not as expensive as many landlords think, and it will definitely save lives in an earthquake zone like Southern California. You know, here, the question is not if an earthquake will come, but when.

There are approximately 35-40,000 soft story buildings in the city of Los Angeles alone, not to mention all the surrounding areas. This is protection the public needs.

Our office is designing an increasing number of soft story retrofit projects, thanks to a federal program. Freddy Mac, or Fanny May do not lend money for these type of buildings and for refinancing purposes, landlords increasingly are forced to upgrade their soft story buildings. Retrofitting also has a positive effect on insurance for these buildings. I would like to hear your comments and experiences on this issue.

Re-posted from our newsletter originally sent on 6/13/2013

UNDERSTANDING ENGINEERS

To the optimist, the glass is half-full.
To the pessimist, the glass is half-empty.
To the engineer, the glass is twice as big as it needs to be. :)

Re-posted from our newsletter originally sent on 2/15/2014

CAMPAIGN PROMISE UPDATE!

Do you guys remember one of my articles about the campaign promises of the final two candidates for the mayor of Los Angeles Eric Garcetti and Wendy Gruel? Both candidates were against the city business taxes and said they would abolish it. A very surprising promise by any democrat, right? But they promised...

Just to refresh your memories, Los Angeles demands a "gross receipt" based sales tax if your business is located in Los Angeles. This tax has nothing to do with earnings or losses of your company, it is based on the gross receipt of your yearly income. A totally absurd idea -- just ask any business man who has ever paid taxes after a losing year in business, like almost anybody in the construction industry for the last 4-5 years.

Fast forward. Eric Garcetti is the winner of the runoff with Wendy Gruel. A few weeks ago I was invited to a dinner with Garcetti, and another two hundred or so people. He was very nice, talkative, a very mayoral figure. When I found myself shaking hands with him, I just had to ask him about this promise. It caught him by surprise; he wasn't prepared for a question like that. The only answer he had was, that is a very difficult situation and he has no real answer how to replenish the city's lost revenue if they abolish this tax. He quickly turned to another person to shake hands with.

Just another campaign promise up in smoke.

Re-posted from our newsletter originally sent on 2/15/2014

BLESSING OR CURSE (EXPONENTIAL GROWTH AND THE EXPO LINE)

I believe Shakespeare once said (and, no, I wasn't there at the time), "There is only one thing constant in life and that is change." True. Particularly when talking about the city of Santa Monica.

I've been doing business in Santa Monica for 39 years, but never experienced anything like what the city is currently undertaking. I think Santa Monica is becoming the most European style city in Southern California. Small service oriented businesses like shoe stores, hardware stores, repair shops, old diners and alike are squeezed out of the area, giving room to trendy coffee shops, bistros and expensive stores. In recent years, Santa Monica has become home to a thriving tech sector known as the Silicon Beach. All these techies have a different life style. They are mobile, not ready to settle down and have a family. They want to live in an apartment or condominium, spend their free time at the beach, sip wine in a trendy restaurant, or take a walk on the busy 3rd street promenade, watching street performers showing off their skills. Once unimaginable mixed use buildings, so common in European cities, are popping up all over. Small apartment buildings are giving way to huge buildings, sometimes over a hundred units apiece. This trend is just going to continue, and quite likely intensify, with the proposed Expo Line expected to open in 2016. The Expo Line will be the only light rail mass transportation in the Los Angeles area reaching the beaches.

Who is to blame -- or praise -- for all these changes?

The unprecedented number of projects has surfaced since a major change of the city's land use plan a few years ago. The city is also in the middle of many zoning changes along the future Expo Line.

Can you imagine on a nice summer day, all the people who want to spend the day at the beach and don't have to worry about parking anymore? There are several million like them living in the greater Los Angeles area – who will flock to Santa Monica on the Expo Line. I think it'll be a zoo. It will definitely be a blessing for the local businesses and therefore for the city coffers, but I think it'll be a curse for the people, especially the older folks living in Santa Monica.

What do you think? Is it really a blessing or a curse? Or both?

Re-posted from our newsletter originally sent on 2/15/2014

A LITTLE INSIGHT INTO ENGINEERS

An engineer was crossing a road one day when a frog called out to him and said, "If you kiss me, I'll turn into a beautiful princess." He bent over, picked up the frog and put it in his pocket. The frog spoke up again and said, "If you kiss me, I'll turn back into a beautiful princess and stay with you for one week." The engineer took the frog out of his pocket, smiled at it and returned it to the pocket. The frog then cried out, "If you kiss me and turn me back into a princess, I'll stay with you for one week and do anything you want." Again, the engineer took the frog out, smiled at it and put it back into his pocket.

Finally, the frog asked, "What is the matter? I've told you I'm a beautiful princess and that I'll stay with you for one week and do anything you want. Why won't you kiss me?" The engineer said, "Look, I'm an engineer. I don't have time for a girlfriend, but a talking frog - now that's cool."

Re-posted from our newsletter originally sent on 10/16/2013

IS OUR NEWSLETTER SO INFLUENTIAL?

Who would have thought that our bite-size structural news e-blasts have such a powerful impact? I'm sure you remember the story I wrote about my "pet project" -- how dangerous the soft story buildings are in Los Angeles and that the city of San Francisco has enacted an ordinance to upgrade about 2,000 such buildings. I had discussions with many of my readers, who responded to my article, agreeing with me about the necessity of similar action by our own city council. One of the architects, Mr. Doug Breidenbach, AIA, with whom I've been doing business for a few decades, has an inside track to city councilman Mr. Karo Torossian and his office. Recently he spent considerable time meeting and discussing the necessity of similar actions with Mr. Torossian.

Here comes the break-thru. Another Los Angeles city council man, Mr. Tom LaBonge, who is also concerned with the situation, has just requested, by a motion, that the city council consider instructing the Department of Building and Safety of Los Angeles to provide an inventory of thousands of these so-called soft-story buildings. An inventory is the necessary first step of identifying and cataloging these buildings to see what impact these would have on the safety of the citizens of Los Angeles, particularly the people living in them. Just a reminder, during the 1994 earthquake 16 people died just in the Northridge Meadows apartment alone. That's only one building! And it was all due to this soft story style building.

One thing that must be considered is the economic hardship on landlords to retrofit these buildings, and how these costs can be mitigated by ways of tax incentives, federal grants or having the costs of this construction be passed onto the tenants living in those buildings.

Very interesting development, our office will follow up and report on this topic as it develops.

Re-posted from our newsletter on 10/16/2013

H/3 - A CAUTIONARY TALE

We are very much into real estate frenzy, as you know. In the last 8-12 months we've heard many stories about bidding wars, properties sold over the asking price, etc. Some people, afraid that they might lose out on yet another dream home, aren't doing the necessary background checks for the property they want to buy, or actually end up buying. Usually home inspectors bring up the obvious problems with a house, but the costly and most important structural issues can remain undisclosed. I want to bring up a very common situation our office faced several times recently, so it appears to be "trending", as they say.

Building laws for hillside properties have changed drastically since the 1994 Northridge earthquake. Our office was involved in over 400 home structural inspections and helped the local Building and Safety departments to craft new "Hillside Ordinances" to avoid the most common hillside construction problems. There are several related new building laws, but I think the most important is the H/3 rule. This rule requires the foundation of a new construction, or remodeling of an old one, on a hillside to be of a minimum depth, without consideration of the underlying soil characteristic, based on the height of the existing slope only. Without going into the technical details, foundations on hillsides, without exception, have to be on deep piles - sometimes 40, 50 or even 60 feet deep.

Recently our office faced the unpleasant task of explaining to a few new home owners that their proposed addition on their recently purchased hillside property would be much more expensive than they thought at the time of the purchase of the property, because of this H/3 rule.

My advice is to consult a soil engineer, or structural engineering company, or have an approved, recent soil report included in the contingencies of the purchase.

Re-posted from our newsletter on 10/16/2013

Test Loading of Elisabeth Bridge, Budapest, Hungary in 1964

Source: erdekesvilag.hu

"I remember in my younger years, before I became an engineer that a bridge was built over the Danube in Budapest. It was a suspension bridge and slowly but surely the pieces came together hanging from the suspension cables and the bridge was finished. Before it was given to the public for use, a test loading had to be done. One by one trucks fully loaded with sand, buses, street cars and all kind of heavy equipment rolled on to the bridge. The sight was awesome. The bridge was deflecting, stretching, bending to the limit. But the sight what I'll never forget was this. The chief design engineer of the bridge was under the bridge alone, moored in a tiny dinghy on the water, showing the whole world that his is putting his life on the line for his design. Now that's what I call responsibility. It started with the first known building law, Hammurabi's law about 5,000 years ago which stated: "If a building collapses and the owner's son dies, the builder's son must be put to death". Serious stuff..."

Re-posted from our newsletter on 12/12/2013

UNDERSTANDING ENGINEERS

Normal people believe that if it ain't broke, don't fix it.
Engineers think that if it ain't broke, it doesn't have enough features yet.

HERE I GO AGAIN!

If you’ve been reading my newsletters for a while, you know my pet peeve – soft story buildings. For Los Angeles, all the neighboring cities and for all of the state of California it would be so much safer by retrofitting these buildings. The issue is, as always, cost and incentives.

Last month, I participated in a think-tank meeting for seismic related issues in the Los Angeles area. Among other things -- like geology, seismic preparedness, seismic faults, etc. -- the soft story issue came up as one of the most pressing items for structural engineers recently. One of the panelists was Lucy Jones from USGS, who was recently hired or "loaned" to the city of Los Angeles to help the city put together a list of under reinforced concrete high-rise and "soft story" buildings. You could see her on TV rather frequently answering questions about the recent La Brea earthquake. She is known as the Earthquake Lady.

There were suggestions for mandatory upgrades by new city, county or even state ordinances, state bonds to finance construction -- because actually this is more of a state, than city problem -- tax incentives for landlords, etc. All of these have been discussed before, but one suggestion stood out and it wasn't mine. Dog gone it!

For departments of public health, health inspectors go to restaurants and grade them for cleanness and other health related issues. The restaurants get an A, B or C and those placards have to be posted at the entry of the restaurants with big blue letters. Restaurant owners were so much against it at the beginning, fearing a loss of customers. Today it is a normal thing to check out a restaurant's grade. I know that I wouldn't eat in a restaurant with a C rating. The bottom line is that restaurants really got much cleaner since this system came into law.

Why not to do a similar action for apartment buildings? Apartment owners and landlords are already paying a yearly fee for inspectors to check out the apartments for health and other issues. It would be simple: make landlords post a sign issued by the local Building and Safety inspectors on the front elevation of the building indicating that this building is a dangerous place to live in. This would be a tremendous incentive for landlords to upgrade their buildings in fear of losing tenants.

No mandatory upgrade, no political issues, no deadlines, it would be voluntary only.

Problem solved, and in a few years the majority of soft story buildings would be fixed.

The biggest questions is, of course, why didn’t I think of that?!


What do you think? I'd love to hear your thoughts on this.

SHAKING ALL OVER

In light of the recent earthquakes I thought that sharing a few lesser known facts will help to understand what earthquakes are actually all about.

The earthquakes of California are caused by the movement of huge blocks, or plates, of the earth's crust - the Pacific and North American plates. The Pacific plate is moving northwest, scraping horizontally past the North American plate at a rate of about 2 inches per year, which is about the rate your fingernails grow. (This maybe explains why my wife has to go to the manicurist so many times a year.:)) You can compare this movement to when you snap your fingers. Before the snap, you push your fingers together and sideways. Because you are pushing them together, friction keeps them from moving to the side. When you push sideways hard enough to overcome this friction, your fingers move suddenly, releasing energy in the form of sound waves that set the air vibrating and travel from your hand to your ear, and you hear the snap. The same process goes on in an earthquake. Slow movements in the earth's outer layer push the sides of the faults together. The friction across the surface of the fault holds the rocks together so they do not slip immediately when pushed sideways. Eventually enough stress builds up and the rocks slip suddenly, releasing energy in waves that travel through the rock to cause the shaking that we feel during an earthquake.

In Northern California, the last major earthquake was 100 years ago in 1906 in San Francisco. It was believed to be a 7.8 magnitude quake with over 3,000 people were killed and 225,000 people were homeless. This, of course, was much larger than the 6.9 the 1989 shaker. In Southern California, the last major earthquake on the San Andreas Fault was more than 150 years ago in 1857, rupturing the fault from Central California to San Bernardino. Few people lived in the area, so there was very little damage. Further south along the San Andreas Fault, from San Bernardino through the Coachella Valley to the Salton Sea, more than 320 years have passed since the last major earthquake (around 1680). It is still storing and building up more and more energy for some future earthquake. Another major earthquake is likely to happen on this section of the fault within our lifetime, and will shake all of Southern California. How do we know that? There is a stream bed named Carrizo Plain National Monument that crosses the San Andreas Fault north of Los Angeles and is offset almost 300 feet horizontally and growing. The sediments in the abandoned stream bed are about 2,000 years old, more or less. If we assume movement on the San Andreas has cut off that stream bed within the last 2,000 years, then the average slip rate on the fault is more or less 2 inches per year. (Do you remember my wife's fingernails?) This does not mean the fault slips 2 inches each year. Rather, it stores up about 2 inches of slip each year to be released in infrequent earthquakes. The last earthquake offset the stream bed about 16 feet. If we assume, and it is only an assumption, that all earthquakes have 16 feet of slip, we will have earthquakes on average 100 years: 16 feet divided by 2 inches per year equals about 100 years. This does not mean the earthquakes will be exactly 100 years apart, but since the last major earthquake in Southern California was in 1857 more than 150 years ago, this "Big one" is very overdue. It is only a matter of time before this major earthquake strikes Southern California, which will be large enough to cause extensive damage throughout the entire region.

During the 1994 magnitude 6.7 Northridge Earthquake, intense shaking affected a much smaller area. Northridge was not a major earthquake and very few people have experienced one. In comparison, the Northridge 6.7 earthquake lasted only 7 seconds and ruptured only 9 miles. The theoretical 7.8 "Big One" will last about 110 seconds, almost 2 minutes and rupture the earth for about 250 miles, similar to the San Francisco one in 1906. Imagine the horrible 9.1 earthquake in 2004 in Sumatra, Indonesia, which created the devastating tsunami, killing about 300,000 people, lasting about 500 seconds -- more than 8 minutes, rupturing the earth more than 750 miles, twice the distance from Los Angeles to San Francisco.

In this theoretical, but very likely 7.8 earthquake along the San Andreas Fault, the surface will offset the ground by more than 20 feet in places, and bend or break any road, railroad, pipeline, aqueduct, or other lifeline that crosses the fault. In some areas, the ground will shift violently back and forth, moving nearly 6 feet per second - shoving houses off foundations, sending unsecured furniture and objects flying. The overall shaking in this earthquake will be more than 50 times the shaking produced by the Northridge earthquake. Thousands of older buildings will collapse, and another 45-50,000 will be a complete economic loss. How can we greatly minimize this potential damage? The answer is very simple. We have to understand that the "Big one" is coming; it is not a question of if, but when. We have to be prepared. Building codes have to be upgraded regarding building performance in earthquakes. Especially the very vulnerable, older, under reinforced concrete high rise and soft story, or tuck-under apartment buildings, which have to be retrofitted. The intent of the building codes is to protect people during an earthquake, not to keep buildings functional after an earthquake. My intent in this article was not to scare people, but to have a little more understanding of earthquakes and the role of structural engineers to minimize loss of life and property in our earthquake prone area of Southern California.