EARTHQUAKE DISASTER REDUCTION IN CHINA ABSTRACT

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1 Zifa Wang Director and Research Professor Institute of Engineering Mechanics 9 Xuefu Road, Harbin, China, zifa@iem.net.cn Research interests: earthquake engineering, earthquake insurance, and information technology Prof. Luis Esteva has been a long-time friend of China, especially with Institute of Engineering Mechanics (IEM), China Earthquake Administration. He visited IEM and China in early 1980s when China was still in its early stage of opening to the outer world. When I visited Mexico in June, 2004 for his support of China s bid to host 14WCEE, he instantly supported personally our proposal. During 13WCEE in Vancouver, Canada, as the President of IAEE, he was instrumental in organizing the Conference and witnessing China s successful bid (see picture bid.gif). During the closing ceremony, he was also congratulatory to China for its bid, and his genuine friendly altitude toward China has made him largely popular among Chinese researchers on earthquake engineering (see two attached pictures). In July, 2005, he visited IEM and China again. His lecture on perform-based earthquake engineering has helped young researchers in IEM to understand the frontline research results outside China. His meeting with deputy director general of China Earthquake Administration has been very helpful for us in soliciting supports for organizing 14WCEE in China. As the secretary general of Chinese Association of Earthquake Engineering and the director of Institute of Engineering Mechanics, I look forward to his continuous advice and support in the future. May health and wealth be with him forever! Zifa Wang August 18, 2005

2 EARTHQUAKE DISASTER REDUCTION IN CHINA ABSTRACT This paper starts with the broad definition of three major areas of work under China Earthquake Administration for earthquake disaster reduction. The detailed contents and measures for every task, combining with the introduction to China Digital Earthquake Observation Network, is then defined and explained. A mathematical formula, based on economical impact of every factor in earthquake disaster reduction, is proposed to consider the overall effect of every measure for earthquake disaster reduction. Finally, comments toward future direction of earthquake disaster reduction in China are discussed. Introduction The first destructive earthquakes since the founding of People s Republic of China occurred on March 8, 1966 in Xingtai, Hebei Province, with a magnitude of 6.8 and 7.2. The quakes killed more than 8,000 people and injured another 38,000. More than 5 million houses collapsed in the two events. Since then, the government started to realize the impacts of earthquakes, and subsequently, China Earthquake Administration (CEA, then called State Seismological Bureau) was established in 1971 to deal with the taunting task of earthquake disaster reduction. Since its formation, CEA has undergone a series of evolution in its short history. The name has changed from State Seismological Bureau to China Seismological Bureau in 1998, and finally to China Earthquake Administration in The staff team within CEA has grown from a few dozens of members to over 12,000 full-time members, including over 8,000 technical personnel. Every province in China has its provincial branch for earthquake administration, and local branches are also set up under provincial guidance. In addition, there are 5 major research institutes and a number of other administration institutes within CEA. These institutes, together with provincial earthquake administration branches, work under CEA as a large composite team for earthquake disaster reduction in China. As one of the very few ministry level government agencies worldwide only for earthquake disaster reduction, CEA s focus on earthquake disaster reduction in China has gradually evolved from earthquake observation, monitoring and prediction only to inclusion of preparedness, prevention measures and the recent expansion to emergency response and management. These three areas of work form the foundation for the daily administrational work and the project planning within CEA. Earthquake observation, monitoring and prediction Earthquake observation, monitoring and prediction have been one of the top priorities for CEA. With over 30 years of continuous construction, China now has accumulated a network of over 2,000 seismic observation stations. Another network of earthquake precursory observation is also built. With these networks in place, China has the monitoring capacity as defined in the

3 following. M 4.0 M 2.5 M 1.5 M 1.0 nation wide 50% land areas provincial capitals and their adjacent areas in the eastern part of China capital area On the other hand, earthquake prediction has been one of the unique administration areas in China. There are basically four different types of predictions as defined in the following. Long-term Prediction:a few years to tens of years or longer Mid-term Prediction:a few months to a number of years Short-term Prediction:a few days to a few months Imminent Prediction: within days Although much progress has been made in earthquake prediction in China, the overall accuracy of earthquake prediction is still in its infancy stage. The historical successful example of predicting the Haicheng Earthquake in 1975 was a combination of empirical experiences and earthquake observation, which is not readily duplicable in other cases. It is said that the success rate of short-term prediction is close to 37% while it is higher for long-term and mid-term predictions. It becomes more difficult to predict imminent occurrence of earthquakes. The current status is that a few types of earthquakes could be predicted under certain conditions, but the prediction relies more on empirical experience than scientific analysis. Earthquake prediction is still a global challenge for earthquake scientists. Seismic design for structures Earthquake preparedness and prevention measures Seismic design codes for structures were completed in China as early as Since then, a number of improvements have been made, resulting in modified design codes in 1974, 1978, 1989 and The current seismic design code of buildings is prepared for the purpose of carrying out the policy of giving priority to the prevention of earthquake disasters so that when buildings are made earthquake resistant, damage to buildings, loss of life and economic losses will be minimized. The principles for the design code can be summarized as the following. When buildings designed based on the code are subjected to the influence of frequently occurring earthquakes with an intensity of less than the fortification intensity of the region, the buildings will not be, or will be only slightly damaged and will continue to be serviceable without repair; When they are subjected to the influence of earthquakes equal to the fortification intensity of the region, they may be damaged but will still be serviceable after ordinary repair or without repair; When they are subjected to the influence of unexpected rare earthquakes with intensity higher than the fortification intensity of the region, they will neither collapse nor incur damage that would endanger human lives.

4 Raising public awareness of earthquake disaster mitigation Raising public awareness has been proven to be effective in past earthquakes. For example, during Niigata Chuetsu Earthquake of October 23, 2004, a number of people escaped the disaster because of prior knowledge on how to respond during an earthquake. This verifies the fact that public awareness program is effective in reducing especially casualties during an earthquake. In China, a number of earthquake exhibition halls and special libraries are set up to educate the public. Outreach programs are sometimes incorporated into extension education for both the general public and students in classrooms. Improvement of legislation system In order to increase the effect of earthquake disaster reduction in China, the People s Congress of People s Republic of China promulgated in 1997 the national Law of the People s Republic of China on Protection against and Mitigating Earthquake Disasters. This national law supports and guarantees the works on earthquake prevention and disaster reduction. Based on this law, a number of local regulations and industry stipulations are also issued to materialize the national law into engineering practice. Some of the examples include The Protection Act for Facilities of Earthquake Monitoring and Environmental Condition of Earthquake Observation(1994), Emergency Response Act for Destructive Earthquakes(1995), and Stipulations for Issuing Earthquake Prediction(1998). Another set of result issued as national regulation is the national acceleration zonation map for China (2000), as shown in figure 1.

5 Figure 1 Acceleration zonation map for China (2000) [CEA, 2004]. There are two rules as regard to how to apply the result from this map. Ordinary industrial and civil structures can be built in accordance with the above zoning map Key construction projects and lifeline works have to be constructed in line with the results from dedicated engineering assessment Retrofitting the existing structures There are two reasons why there is a need to retrofit existing structures. One is to fix the weakening of strength due to aging or external damage to the existing structures. Two is to enhance existing structures to be compatible with new design standards. Up to now, retrofitting is performed either to mostly on historical monuments and important structures or to damaged structures during an earthquake. Retrofitting has also been proven to be effective in Taiyuan, Shanxi province. Before Yanggao Earthquake the city of Taiyuan had been retrofitted with the aid from a UN fund. There was obviously light damage in the city for the retrofitted structures, while comparable structures under similar ground motion excitation suffered heavier damage. At this time, gradual and increasing efforts are put forward by both central and local governments as well as private enterprises to retrofit vulnerable structures. Engineering assessment for key projects The national law described in 3.3 provides the basis for the need to assess earthquake safety for large and key projects, especially the national key projects such as the Three Gorges Dam and

6 most of the nuclear power plants. The aim of the project is to determine the ground motion level at or surround a given project construction site via sophisticated engineering approaches. The result from this assessment shall be used to design the project accordingly, if it is different from the zonation map. In a good percentage of the cases where there is a need for sophisticated engineering assessment it is found that the ground motion level appears to be different from the zonation map, which stresses the importance of such a complicated study. Urban Active Faults Detection Projects Starting from 2003 a new national key project, called China Digital Earthquake Observation Network, is under way for a 5-year construction. Included in this project are three networks (seismic observation, precursory, and strong ground motion), three systems (active fault detection, information, and emergency response and commanding), and a training base for rescue teams. Active fault detection system tries to identify active faults in almost all the major cities in China, including the provincial capitals in the country. When the result from this project is compiled, it will definitely help the preparedness and prevention of earthquake disaster if it happens. Earthquake loss estimation Earthquake loss estimation tries to assess the economical impact of an earthquake disaster should it happens. The purpose of this field of work is to identify the most vulnerable spots within a city during an earthquake, and corresponding retrofitting measures are proposed at the same time. For example, in Daqing city of Heilongjiang province, earthquake loss estimation is performed for the whole city as well as the surrounding oil fields, and numerous vulnerable spots are identified for further repair and enhancement. The result can be readily incorporated into city planning. Earthquake Emergency Pre-plan Earthquake Emergency Response In order to better prepare for emergency during an earthquake, the State Council has set up an earthquake disaster relief headquarter within CEA. This headquarter will enact during a destructive earthquake. On April 27, 2001 China International Search and Rescue Team (CISAR) was established with much fanfare. This team is governed by the relief coordinating office within CEA, which is under the administration of State Council of China. There are over 200 members in CISAR with the background of engineering, earthquake science and medicine. CISAR is equipped with advanced tools and communication systems. Emergency relief and rescue Ever since its founding, CISAR has played a major role in relief, search and rescue. It was deployed domestically to Bachu-Jiashi Earthquake and Zhaosu Earthquake in Xinjiang Province. Internationally it was deployed to Algiers, Iran in 2003 and it was again deployed to Indonesia after the great Sumatran Earthquake of The team has won a high fame as a hard working

7 and reliable search and rescue team at the field, thus earn an excellent reputation both domestically and internationally. The mathematical representation of earthquake disaster reduction in China Around the world there are few countries like China that have coordinated central governmental efforts in earthquake disaster reduction. There are many reasons to this. One could be that China has suffered heavily during past earthquakes. In 20 th century, around half of the casualties of earthquakes occurred in China. Over half of the inland earthquakes also occurred within China. The second reason is that Chinese government places a high priority to the importance of human life. Therefore, in 2004, a national goal for earthquake disaster reduction in 2020 was issued, which states By 2020 China should be resistant nationally to an M6 class earthquake, or to the current fortification level in design standards. Developed regions and large cities should have comparable earthquake resistance level comparable moderately developed countries. There are at least two problems to this. 1) How to assess the resistance and scientifically define such a goal? 2) How to get there? The second question can be partially answered if the first question is clearly answered. Therefore, we will focus on the first one. In order to assess earthquake resistance, we need a physical parameter that is a complicated function of many factors. With the existence of such a parameter, the effect of every factor can be studied independently, thus resulting in the identification of most important affecting factors in determining earthquake resistance. Economic loss is proposed to be such a parameter because an earthquake usually only causes damage and loss while creating little benefit. The extent of the damage can be best expressed by the amount of economic loss of the event. Therefore, the 2020 national goal can be expressed via the following formula. Minimize: Total_Loss = Property_Loss + Derivative_Loss + Human_Loss + Commercial_Loss + Other_Losses Where Casualty <= Target_1 Business_Interruption <= Target_2 Property_Loss <= Target_3 Derivative_Loss <= Target_4 From the above, it is clear that if we convert casualty loss into economic loss this becomes a typical problem in operational research. By studying the amount variation of total loss due to the change in every domain of work in earthquake disaster reduction, we can assess the effect of different measures. With such a formula in place, we can at least derive the results for the following questions. 1) What is the most important affecting factor? 2) What is the most effective measure? 3) Where is the problem? and many more.

8 Conclusion China, with its ministry level government agency China Earthquake Administration, has put into a good amount of efforts into earthquake disaster reduction. Earthquake observation, monitoring and prediction, earthquake preparedness and prevention, and emergency response and rescue are three areas of work in reducing earthquake disaster in China. A number of measures have been taken in China to prepare and prevent earthquake should it happens. Furthermore, a national goal for 2020 has been established requiring extra efforts to realize it. A mathematical formula is proposed to further study the problem. At this time, China is planning its 11 th 5-year plan for earthquake disaster reduction. A long-term plan for year 2020 is also simultaneously happening. In the next five years, China will focus on at least the following areas in order to reduce the impacts of potential destructive earthquakes. Earthquake safety for large cities and major metropolitan areas Earthquake safety for rural areas Emergency response for key infrastructure systems Experimental fields in seismically active regions For further reduction of earthquake disaster in China, both international and domestic help are needed and a closer international collaboration is expected in the coming years. References China Earthquake Administration (2003), annual report (2003) Wang, Z. (2005), Research Report for 11 th 5-yearPlan for Earthquake Disaster Reduction, Recent Developments in World Seismology, 2005(7), 17-22