Structures with Human-Induced Vibration – How Serviceability Requirement Improves Vibration Design Concept July 25, 2007
Posted by dionsiringo in Vibration, mechanical vibration, opinion, paper work.1 comment so far
In the past few years, human body motions have quite often caused serious structural vibration problems. We have seen several excessive vibration problems caused by human motion during the service of structures. Human-induced vibrations were sometimes not considered in vibration suppression design due to the fact that the problem itself is primarily serviceability problem. Main considerations for structural dynamic design are safety against the occurrence of major vibration impact to the structures such as: earthquake, wind-induced vibration, traffic-induced vibration or/and impact-induced that might lead to structural failure at a catastrophic level. Human-induced vibrations, which were perceived only as serviceability problem in term of annoyance and disturbance to the users, accordingly have not been addressed properly in design code.
Several latest reports on cases, where human-induced vibrations were found excessive and annoying, however, have changed the common perspective on this problem. The closing of Millenium Bridge in London right after its completion due to excessive human-induced lateral vibration is one major case that took public attention. Thus following this report and some other previous cases, researcher, structural engineers and building authority have work together to accommodate users convenience requirements (serviceability) to provide better structures that suppress the anticipated human-induced vibration.
Entrepreneurial universities June 7, 2007
Posted by dionsiringo in Indonesiana, opinion.add a comment
In the spirit of the slogan “2006, The Indonesian Year for Science”, it worth asking the question how much our scientific communities have contributed to the economy. With the current 0.3 percent of national GDP invested in research and technology, some might argue that it is too soon to ask for such a contribution. But while increasing national investment in research is vital, it is also essential to measure how much economic growth has — and will — emanate from these knowledge investments. New strategies should be developed to avoid the pitfall of the so-called “European paradox”; the conjecture that while European countries have consistently been leading players with top levels of scientific output, they lag behind in the ability to convert this knowledge into wealth-generating power.
During the New Order government of the 1980s and 1990s Indonesia experienced a similar kind of European paradox, only on a smaller scale. Back then, the promotion of high technology was initiated from the top, on the assumption this technology would automatically function as the accelerator of economic growth..
Revitalizing disaster management April 29, 2007
Posted by dionsiringo in Disaster Mitigation, Indonesiana, opinion.add a comment
It seems every story about Indonesia recently involves a disaster. With alarming speed, we have replaced such countries as the Philippines, Nepal and Bangladesh as the most disaster-prone nation in the world. Indonesia, however, is not alone in facing natural disasters. Globally, the number of environmental calamities is rising, mostly owing to an increase in floods.
For the period of 1994-2003, the International Council for Science found floods were the most common natural hazard, making up 33 percent of disasters. Storms were next at 23 percent, epidemics at 15.2 percent, droughts at 15 percent and earthquakes at 7 percent. The remaining disasters included tsunamis, landslides and volcanic eruptions. Hazards related to extreme weather conditions occurred most frequently and often affected the largest areas.
In disaster science, the paradigm is now shifting from knowing that rivers flood to understanding how a flood can cause so much damage. Human beings, not nature, are the cause of disaster losses. It is unrealistic to think that we can engineer the earth to stop disasters, but it is possible to adjust human behavior to reduce their risk.
Indonesia has long recognized the importance of having a disaster management organization….read complete article
Living with and learning from earthquake April 29, 2007
Posted by dionsiringo in Disaster Mitigation, Earthquake, Indonesiana, opinion.add a comment
The two major earthquakes that have struck Indonesia recently caused damage beyond imagination. In 2004 the Aceh earthquake triggered the largest tsunami in modern history. Last month’s quake in Yogyakarta may be not as huge in magnitude as other great historic earthquakes, but the area affected was extensive. The casualties from these two disasters were staggering, and this should remind everyone how earthquake-prone Indonesia is.
Since the devastating San Francisco earthquake of 1906, anti-earthquake engineering techniques have continuously improved…
Minimizing the danger, damage of landslides April 12, 2007
Posted by dionsiringo in Disaster Mitigation, Indonesiana, opinion.add a comment
Every year during the rainy season landslides pose a serious threat to many who live in mountainous areas of Java, Sumatra and several other islands. This year, we have already witnessed two tragic disasters caused by large scale landslides. Heavy rainfall combined with the misuse of land has triggered massive gravitational movements of debris and mud.
The recent toll from the landslides in Jember and Banjarnegara were particularly severe and tragic. However, even though these types of disaster continue to increase in terms of frequency and seriousness, little has been done to prevent, or even, mitigate the possibility.
There is a tendency to focus only on addressing immediate problems rather than anticipating new ones. To make matters worse, many people still merely put this disaster down to an “Act of God”, while in fact prevention of the landslide hazard is both scientifically possible and feasible.
