A colleague forwarded a link to a very interesting presentation by a Japanese engineer who surveyed the earthquake damage at various locations along the coast. It contains a lot more engineering information than all of the media reports I have seen.
Some interesting notes:
Strong shaking does not seem to have caused much if any structural damage. Tsunami damage was the dominant event.
Some types of construction (steel, concrete) resisted the tsunami better than others (wood).
He estimates that Tsunami warning systems that were in place saved hundreds of thousands of lives.
These narrated videos slowly zoom in to several million times magnification, which is enough to see the chemical composition of concrete and steel.
This information may not be directly applicable to structural analysis or design on a daily basis, but it can’t hurt to have some material science background on the materials with which we build.
You’ve all seen the pictures (linked at the bottom of the post) of the spectacular building collapse in Shanghai. At around 5:30am on June 27, an unoccupied building still under construction at Lianhuanan Road in the Minhang district of Shanghai city toppled over. One worker was killed.
These figures show why the building collapsed. The images are from a Chinese newspaper and from the bbs.sina.com.cn website. The translations were forwarded to me in an email (Unfortunately, I can’t read Mandarin).
(1) An underground garage was being dug on the south side, to a depth of 4.6 meters
(2) The excavated dirt was being piled up on the north side, to a height of 10 meters
(3) The building experienced uneven lateral pressure from south and north
(4) This resulted in a lateral pressure of 3,000 tones, which was greater than why the pilings could tolerate. Thus the building toppled over in the southerly direction. Read more…
It may be too late to send comments on the report, but it is still available to download and read. Via the NIST.gov website:
A new draft report released for public comment by the National Institute of Standards and Technology (NIST) provides a comprehensive set of “best practice” guidelines for designing building structures to resist major fires. The document, NISTIR 7563, Best Practice Guidelines for Structural Fire Resistance of Concrete and Steel Buildings, is part of the NIST response to the World Trade Center (WTC) disaster of Sept. 11, 2001, and was developed in conjunction with the agency’s technical building and fire safety investigation of WTC buildings 1 and 2 (the WTC towers) and 7. Read more…
The year 2008 will long be remembered as the start of an economic crisis that has gripped the entire globe – a year that may also have brought to an abrupt end the worldwide construction boom of the past decade that has seen ever-denser cities containing ever-taller buildings proposed from Madrid to the Middle East, from Shanghai to San Francisco. As financial shock waves have reverberated around the world, high-profile tall building projects in virtually all skyscraper cities have been cancelled, delayed, or put on hold in response to the precarious global economic conditions. The question that everyone is now asking – is this the end of the tall ambitions of places such as Moscow, Chicago or Dubai for the short-mid term future?
The correlation between tall buildings and economic recession is not a new one. In 1999 the economist Andrew Lawrence created the ‘Skyscraper Index’ showing how almost all of the world’s tallest buildings throughout history have reached completion virtually simultaneously with the onset of a major economic recession. Using the research and criteria of the Council on Tall Buildings and Urban Habitat (CTBUH), and specifically their annual ’Ten Tallest Buildings Completed Annually’ and projected ‘Tallest 20 in 2020’ research, this paper seeks to examine further the link between skyscrapers and economic cycles, and suggest how the current economic crisis will affect tall building developments in the next decade or so.
Today, the American Society of Civil Engineers issued its latest Report Card for America’s Infrastructure, the fourth since 1998. Never has the need for infrastructure investment received such national attention as it is now in the context of stimulating our economy. Recognizing the importance of informing and contributing to this discussion in a timely manner, we made the decision to release the key components of our 2009 ReportCard two months ahead of schedule. Today ASCE released website the grades for 15 categories of infrastructure, solutions for improvement, and a five year investment need figure.
The overall grade for the nation’s infrastructure is again a D and the cost to bring it up to good condition has risen to $2.2 trillion. In more than a decade, the United States has made no measurable progress in improving either the condition or performance of our roads, bridges, water systems or other vital infrastructure when viewed in aggregate.
Today’s engineers are working across disciplines and driving innovation. MAKE IT WORK. Engineering Possibilities looks at how engineers are envisioning and realizing the future of our built environment by transforming structures, improving environments, enhancing materials, re-inventing building technologies, and advancing forms. This exhibition highlights how inventive strategies for building are born from multidisciplinary research and integrated practice. Small engineering firms, large engineering firms, engineering schools, university labs, materials labs, artists, inventors, and architects are all part of the exchange of ideas – plotting trajectories of innovation. Read more…
Infrastructure is receiving unprecedented attention from President-elect Obama, the U.S. Congress, and the media. ASCE finds itself at a crucial moment to spread our message and participate in the dialog regarding infrastructure improvements.
Yesterday, the House Appropriations Committee released a summary of the House Democratic Leadership’s proposed economic stimulus package, the American Recovery and Reinvestment Act of 2009. Included in the infrastructure and science portions are many of ASCE’s priority issues. For details on the package, visit ASCE’s Government Relations blog.
On January 28, 2009, ASCE will issue important components of our 2009 Report Card for America’s Infrastructure, including letter grades with short conditions summaries for each of 15 categories, solutions for infrastructure improvement, and an overall cost to improve the nation’s infrastructure. The nation’s leaders rely on ASCE to provide expert advice on the condition of the nation’s infrastructure. Early release of the 2009 Report Card is essential to fulfilling that role. Read more…
The Structural Engineering Slide Library was collected over the period 1950 through 1980. It was developed as a visual resource for illustrating structural systems in undergraduate courses in structural analysis and design. Each structure is identified, and a brief description is given.
When I was a TA for a freshmen introduction to structural engineering course, these slides were helpful in providing “real world” illustration of some of the idealized conditions that we were studying.
For example, when explaining about pin and roller supports, it’s helpful to show what a pin (left), and a roller (right) really look like. Read more…
