Tag Archives: Code

S.Korea strengthens Building Code after Quake

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Korea

 

As an update to my post on the Japanese earthquake, there is news from South Korea that the government there is already working to strengthen quake-resistant capacity. 

“We are seeking to revise a construction law to strengthen quake-resistant capacity for two-story and smaller buildings,” the land and transportation ministry said. “The government will complete its final plan for that by next week.”

Under current Korean law, only large buildings with more than two stories and floor space of more than 1,000 square meters are required to be built according to quake-resistant guidelines, and the ministry is looking to expand the quake-resistent guidelines to smaller buildings.  Currently,  smaller structures are not subject to the requirement, even though they make up 84% of the total construction.  

The U.S. is unlikely to adopt new standards in such a lightening fashion.

Comments? Questions?  Drop me a line, or follow me on Twitter @melissabrumback

Japan Earthquake: Engineering that saved lives

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globe showing earthquake activity
Photo: NASA. Cumulative Earthquake Activity (1960-1995).

 

The earthquake that hit Japan one week ago today, which had a reported  magnitude of 8.9, ranks as the 7th largest earthquake ever recorded, and the death toll continues to rise from the trifecta of earthquake, tsunami, and nuclear power issues.    The death toll could have been even worse, however, without the strict Japanese Building Codes which doubtless saved thousands of lives.

According to the New York Times, such features as extra steel bracing, giant rubber pads and embedded hydraulic shock absorbers in high buildings make modern Japanese buildings among the sturdiest in the world during a major earthquake.   Japan has such strict building codes because it is located in the “Ring of Fire,” where over 90% of the world’s total earthquakes occur.

John Wilson of Swinburne University (Melbourne) Centre for Sustainable Infrastructure says Japan’s “stringent” building regulations make the country well-prepared for earthquakes and tsunamis.  “[Building codes] were tightened up a lot in the 1980s – most of the buildings built over the last 30 years in Japan will be subject to very tight seismic regulations,” he said.  “They are designed for quite a high lateral force, to allow for the forces that get generated from such earthquakes… but also in many buildings they add additional features such as additional damping in the buildings to absorb some of the energy.”

During the earthquake, despite being hundreds of miles from the epicenter, Tokyo’s tall buildings literally swayed like trees as the quake shook the ground.  According to structural engineer Bill Faschan:  “The basic idea, particularly (for) a tall building, is it’s supposed to act like a tree. A tree in the wind, it sways back and forth. And in a seismic event, it’s very similar. Obviously, the ground (is) shaking as opposed to the building being moved back and forth by the wind, but (it’s) the same idea. It’s supposed to move. It’s supposed to give.”

Is the U.S. ready for a big earthquake?

Not according to some experts.  Even in the more earthquake-prone areas such as California, they say, the U.S. is far behind Japan in the building technology.  As Donald R. Prothero with the L.A. Times pointed out:

Although California building codes are among the most stringent in the United States (thanks to what the 1933 Long Beach quake, which destroyed nearly all of our unreinforced masonry buildings), they don’t begin to match the standards demanded in Japan. Just consider the high overpasses where the 5 and 14 Freeways meet — which fell in the 1971 Sylmar quake; their replacements fell in the 1994 Northridge quake — and you begin to realize just how vulnerable our infrastructure is. And those quakes were only 6.6 and 6.7 in magnitude.

What comes next for the Building Codes?

Will U.S. jurisdictions create more stringent Building Codes after seeing the Japanese earthquake’s damage?  Although California does take  the likelihood of earthquakes into account its Code, will it now tighten them further?

Drop me a line in the comments to discuss this or any other Construction law topic.  And don’t forget to sign up for email delivery of blog posts directly to your mailbox. 

Friday Extra:  Check out this Blog Post for a simple to understand explanation of the science behind Japan’s earthquake.

Roof collapse investigations: Engineers Say Codes Adequate

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snow collapses roof deck Following on last week’s story about green roofs, including one which collapsed under a weight of snow and ice, engineers speaking to the ENR have stated that Codes are adequate, but that they may need to be adjusted in certain situations:

[E]ngineer sources for this article say existing building codes are adequate if designers allow for a factor of safety. But Levy [Matthys Levy, chairman emeritus at Manhattan-based Weidlinger Associates]  recommends designers make proper allowances for snow accumulation such as when designing roof structures near parapet walls, especially those that are four feet or higher.

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Multi-level roofs with steps instead of roof flashing can also be problematic with snow accumulation on a first-story portion, for instance, piling up against the second story, Levy says. “It’s best to avoid stepped designs unless you design for them,” he says. While an average of 40 psf may be adequate for designing most of a roof, designers should allow 60 psf to 80 psf for the parapet wall, he says. And mountainous regions may require twice as much strength, he says.

Garrick Goldenberg, professor of structural engineering at Wentworth Institute of Technology in Boston and chief structural engineer at Chappel Engineering Associates in Marlboro, Mass., said that while state building codes address snow drifts with requirements for the shape and slope of a roof, this year’s record snowfalls and ice accumulation with little thawing has led to a greater number of collapses.  In sampling snow at Chappel Engineering in early February, Goldenberg says his group found that even two feet of freshly fallen snow or more totaling 16 to 20 lb/sf was not a danger to buildings. On average, people assume fresh fallen snow produces eight pounds of pressure on a roof per square foot.

However, invisible loads caused by accumulation of ice have been a serious problem since ice weighs 7.5 to 8 times more per cu ft than snow. “In many cases, even before reaching two-foot snow loads, we were in excess of 30 pounds because of the ice,” he claims.

For more, go to the ENR full story: Ice, Snow Take Toll on Northeast Roofs, But Engineers Say Codes Are Adequate.

What are your thoughts about current Codes, in light of the many collapses in the Northeast and Midwest?  Legally, does designing to Code, but failing to take into account likely weather events, make your design deficient?  I’ll post some of my thoughts in a subsequent post, but share yours below.

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 Photo: “Deck roof collapse”   by Derek K. Miller via Creative Commons license/Flickr

Tues Tip: Prepare for new ADA Standards

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ADA sign   The Americans with Disabilities Act (“ADA”) has been a standard in construction since its was signed into law by President George   H.W. Bush in 1990.  However, there are significant new changes coming, thanks to a new Department of Justice Rule and Standards.  The new Rule becomes effective in a little over two months– on March 15, 2011.  The new Standards are not mandatory until next year (March 15, 2012).  Buildings can currently be constructed to meet either the current or the 2010 Standards; however, the 2010 Standards will become mandatory next year.

According to the Department of Justice, some of the changes that design for new construction will need to accommodate include:

1. Reach Range Requirements (Section 308)

The reach range requirements have been changed to provide that the side reach range must now be no higher than 48 inches (instead of 54 inches) and no lower than 15 inches (instead of 9 inches). The side reach requirements apply to operable parts on accessible elements, to elements located on accessible routes, and to elements in accessible rooms and spaces.

2. Water Closet Clearances in Single User Toilet Rooms (Sections 603, 604)

In single-user toilet rooms, the water closet now must provide clearance for both a forward and a parallel approach and, in most situations, the lavatory cannot overlap the water closet clearance. The in-swinging doors of single use toilet or bathing rooms may swing into the clearance around any fixture if clear floor space is provided within the toilet room beyond the door’s arc.

3. Common Use Circulation Paths in Employee Work Areas (Sections 203.9, 206.2.8)

Under the 1991 Standards, its was necessary to design work areas to permit an employee using a wheelchair to approach, enter, and exit the area. Under the 2010 Standards, it will be necessary for new or altered work areas to include accessible common use circulation paths within employee work areas, subject to certain specified exceptions.

4. Location of Accessible Routes (Section 206)

All accessible routes connecting site arrival points and accessible building entrances now must coincide with or be located in the same general area as general circulation paths. Also, where a circulation path is interior, the required accessible route must also be located in the interior of the facility.  [Editor’s note: this requirement will help meet the Universal Design principle of equitable use by all persons.]

These are just some of the many changes.  The DOJ ADA website offers several fact sheets and the actual regulations, so take some time to review it if you have not already.

Questions about the Americans with Disabilities Act?  Comments about how these changes will affect your projects and how you are adapting plans to accommodate these coming changes?  Drop me a line in the comment section below.  Also, be sure to enter your email to get delivery of posts direct to your email inbox to be sure you never miss a post.

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Photo:  “Minneapolis Road to Freedom 71“by Transguyjay via Flickr/Creative Commons License.

LEED Credibility Challenged– UPDATE

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 A group of local citizens, designers, and school board Building Committee members in Eagle Ridge, Wisconsin has issued a statement expressing their belief that LEED certifications are now suspect, following the failure of the USGBC to withdraw LEED Certification from the Northland Pines High School.  The group had appealed a decision to dismiss their claims that the LEED Gold certification for the school should be revoked, despite clear evidence which, they claim, shows that the building did not meet specific ASHRAE Standards, which are prerequisites to getting a LEED (green) building certification.

 They call into question the value of LEED certification if there is no verification of a purported building’s “green” credentials.

 You can download their statement of concern “USGBC and LEED Credibility Destroyed”.

 For more information relating to the case, Stephen Del Percio’s article “Wild Week for Green Real Estate Law” is an excellent summary.

 As previously mentioned on this blog, there is no clear idea of how the Courts would treat any LEED-specific claims.  Yet.  Stay tuned.

 UPDATE:  This afternoon, the USGBC has issued a statement standing by their findings:

LEED’s intent, and USGBC’s mission, is about helping people learn about and understand how to design, build and operate better buildings.  Buildings are complex systems of systems and any of the 100,000 of decisions associated with design, construction and operation can always be second-guessed. We are confident that our due diligence has been more than sufficient to put these issues to rest, and we are moving forward to focus our efforts where they do the most good — advancing the market uptake of green buildings and communities that is at the heart of our work

The full statement and commentary can be reviewed at Chris Cheatam’s article “Breaking: USGBC Stands by Its LEED Challenge Decision.”