A SEISMIC ZONING MAP CONFORMING TO EUROCODE-8, AND PRACTICAL EARTHQUAKE PARAMETER RELATIONS FOR THE NETHERLANDS

A zoning map for earthquake intensities and a relation between intensi ty and design ground acceleration are presented, conforming to Eurocod e 8, the European earthquake building code. For the southeast of the N etherlands, reduced or simplified seismic design procedures may be use d. For the remainder of the country, where expected intensities are ve ry low, the provisions of Eurocode 8 need not be observed. From the Ne therlands data set, the linear frequency-magnitude relation for the te ctonic earthquakes is re-calculated. A correlation between intensity a nd magnitude is determined and compared with similar relations in Cali fornia and Germany. The radius of perceptibility estimated from the lo cal magnitude is more accurate than that estimated from the maximum ob served epicentral intensity. This radius is substantially greater in t he Netherlands than in California for the same epicentral intensity. T he maximum expected earthquake for the Netherlands is estimated at abo ut 6 1/4 local magnitude.