DEVELOPMENT OF REALTIME DISASTER MITIGATION SYSTEM FORURBAN GAS SUPPLY NETWORK

摘要

To cope with earthquake related secondary disasters, the new real-time disaster mitigation system for acity gas network has been developed by Tokyo Gas Company. Since 1998 for the purpose of realization ofdense real-time seismic motion monitoring, quick gas supply shut-off, prompt emergency response andefficient restoration work. In 2001, Tokyo Gas successfully started the operation of SUPREME, whichemploys 3,800 new SI sensors and remote control devices at all the district regulator stations in its servicearea (3100km2). SUPREME can observe the status of 3,800 district regulators and shut them off remotely,if necessary. The remote shut-off using SUPREME can realize quick gas supply shut-off and effectivelyreduce gas leakage risk during earthquakes. The SUPREME can also conduct damage assessment for gaspipe with enhanced use of GIS. To estimate the distribution of SI values and liquefied depth moreprecisely, digital map, geological map, topographical map and borehole logging data of about 60,000 siteswere collected and compiled. Site amplification factors for SI values were estimated at the boring points.Then, spatial distribution of the site amplification factor was estimated based on weighted average of theamplification factors of surrounding boring points and the geological / topographical maps.