Earthquake Response And Its Application to Energy Supply System JIN Xing GUO Xun LI Shanyou Institute of Engineering Mechanics (IEM) China Seismological Bureau 29 Xuefu Rd Harbin

Contents 1.Earthquake activities and seismic disasters in China last century 2.Situation of Early Warning System in China 3.Introduction to Earthquake Response System in the near future 4.Application to energy lifeline system

Earthquake Hazard in the Last Century Earthquake with magnitude ： 380 Earthquake with magnitude ： 65 Earthquake with magnitude great than 8.0 ： 7 Earthquake with magnitude great than 8.5 ： 2 Left total deaths: 590,000 Total wounded ： 760,000 Collapsing Room ： more than 60,000,000 Direct Economic Loss: thousands of million RMB Indirect Economic Loss: tens of thousands of million RMB million RMB

≥8.0 The Distribution Strong Earthquake (M≥6.0) In 20 th Century

Ms ： 7.8 Ms ： 7.8 Date ： July, 28, 1976 Date ： July, 28, 1976 Deaths ： 242,000 Deaths ： 242,000 Loss ： 13,275 million RMB Loss ： 13,275 million RMB Tang Shan Railway Cars Factory

Earthquake Activity Trend 1990

Peak Acceleration Zoning Map of China (2000)

2. Situation of Earthquake Warning System in China (1) Daya Bay Nuclear Power Plant (Shenzhen, Guangdong Prov.) From 1991, Instruments include: 6 units of 3-component accelerometer, 2 units of 3-D Trigger, 4 units of peak acceleration recorder and control unit. Distribution: around the center, both on ground surface and on key structures. Alarm Philosophy: S-wave alarm. Functions: warning to control center during a earthquake providing useful information after the earthquake for facilities maintenance

2. Situation of Earthquake Warning System in China (2) Administrative Center of Daqing Oil Field From 1992, 8 detecting units (seismometer and accelerograph, ground surface and downhole) connected by digital communication network, S-wave alarm Criteria. Ertan Hydropower Station (Sichuan Province) From 1996, SQC-III accelerograghs Qinshan Nuclear Power Station (Zhejiang Province) From 1994, 4 digital accelerographs

3. Introduction to Earthquake Response System in the Future Earthquake Response System Earthquake Warning SystemEarthquake Emergency System Communic ation Links Data Processing & Policy Decision Center Contin gency Schem e Evaluatio n System for Earthqua ke Disaster EarthquakeMonitoring System CommunicationLinks Data Processing andPolicy DecisionCenter Evaluation System for EQ Disaster Contingency Scheme

General Considerations About Earthquake Warning System (EWS) (1)National EWS: Earthquake Monitoring Network Strong Motion Network: 2000 Digital Accelrographs Special Communication & Information Network Control Center: China Earthquake Disaster Prevention And Reduction Center (Beijing) Objective: Large Earthquake Reporting ≤10 min Emergency Response ≤25 min Seismometers:636 Fixed and 1000 Mobile

(2). EWS for Major Monitoring Cities: Such as Beijing, Tianjin, Kunming, Lanzhou, Urumchi etc., to establish regional dense earthquake intensity quickly reporting network. (3). EWS for Important Infrastructures: Such as Nuclear Power Plant, Hydropower Station, Highway and High Railway, to establish dense telemetered accelarograph network.

The Distribution of Digital Seismic Stations State Digital Seismic Station Net Regional Digital Seismic Station Net (Up to the end of the tenth five year Plan (2005))

The Distribution of State Digital Accelerograghs ( To be completed before 2005) First-class Monitoring Area Second-class Monitoring Area

4. Application to Energy Lifeline System (1)Basic Idea: to build earthquake monitoring system including accelerographs, communication system and control center. (2)Basic principle: a. S-wave Alarm (40 gal, 80 gal, 120 gal); b. Front Alarm (arrival time difference); c. P-wave alarm (initial motion). d. The determination of earthquake parameters (magnitude, location, time); e. Evaluation of earthquake damage losses Analysis and estimation of strong ground motion along energy supply system Emergency plan

This is a pipe line with length of 5400 km which will transport gas From Tarimu and Changqing Oil Field to provinces of East China (Anhui, Jiangsu, Shanghai, Zhejiang). Because of the widely distributed potential earthquake sources, we can not establish a EWS like that in Mexico or in Hualien, Taiwan. S-wave Alarm criteria will be applied by setting detecting units every 50km along the pipeline, some existing instruments operated by different related provinces will included in this Earthquake System. Considerations on EWS for the Gas Transportation Project

Gas Transporting Tibet Railway Power Transporting Water Transp. Four National Major Lifeline Projects

Conclusion Remarks China is an earthquake-prone country, energy supply system suffered severe damages in the past strong earthquakes; The existing Earthquake Warning System is just a primary step; The development of the national economy needs urgent effective EWS; We hope as more as possible cooperation with the members of APEC on this filed

Consists of distributed seismic accelerographs, communication links and controlling center; Can quickly response to seismic event; Losses can be minimized through promptly countermeasures. Basic Concept of EWS:

S-wave Alarm : The alert is issued when the acceleration exceeds pre-set levels, such as 40 gal (A), 80 gal (B) and 120 gal (C). Three levels correspond to different countermeasures. Problems: Alarm is too late to give enough time useful for the countermeasures; Frequent false alarm is issued for the harmless small earthquake. Alarm Philosophy （ 1 ） C A B S-wave Alarm

Front Alarm: The earthquake motions are detected as early as possible near the source to prepare against the earthquake before seismic motion reaches the site, using the difference of transmission velocities of electric signal and seismic wave. Front Alarm Margin Time : t 2 -t 1 -t 1 ´ Focus Alarm Philosophy （ 2 ）

P-wave Alarm (From UrEDAS, Japan) Alarm Philosophy (3) P-wave Alarm: Alarm is issued by the detecting of P- wave. Usually, P-wave alarm is done by the trigger of at least two adjacent accelerometers. If the pre-set threshold level is to low, false alarm occurs very often.

In the case of single station, the epicentral azimuth may be estimated by the amplitude of initial part of two horizontal traces, the epicentral distance may be calculated by the arrival time difference of P and S waves. As for multi-station, the earthquake location may be determined using the arrival time of P waves at 4 stations. Method for location determination

Alarming system E When the state or regional telemetered station network center receives the information of P wave at some stations, they automatically transmit one alarming single to early alarm system center of energy supply system closing to the epicenter. E After the earthquake parameters transmit to the early alarm system center, the alarm system intelligently estimate the damage of energy supply system by use of the earthquake parameters and the information from the dense telemetered accelarograph network, and then take appropriate emergency measures.

What Should We Do in the Near Future To establish National EWS, some regional EWS and EWS for important infrastructure, New type of earthquake detecting instruments have been produced such as GDQJ-I and GDQJ-II.

Features of GDQJ Accelerograph (1) Data Acquisition: 16 bit of A/D converter with 3 channels, 90dB of dynamic range, 62.5, 125, 250 and 500 Hz of sampling rate Sensor: Triaxial Force Balance Accelerometer, ±2g full scale range, 140 dB of dynamic range and 0~80 Hz of bandwidth Trigger: alarm threshold or STA/LTA Storage: 4 Mbyte CMOS RAM System Control: configure sample rate, filter type, trigger type and volting, maintains communications and event storage

User Interface: Full RS-232 interface with modem control Intelligent Alerting: Auto initiate communications when an event is detected Timing: Free running oscillator and GPS Power Supply: 100~240 Vac 50/60 Hz with 10AH 12V battery Driving Software: Windows 98 based and version for DOS platform Features of GDQJ Accelerograph (2)