As a result of sorting out, estimating and cataloging of historical earthquakes, from the year of 2 A.D. to Aug., 1949, we found that there were 2187 earthquakes with M≥3.0 in the area of the Yellow Sea and its adjac...As a result of sorting out, estimating and cataloging of historical earthquakes, from the year of 2 A.D. to Aug., 1949, we found that there were 2187 earthquakes with M≥3.0 in the area of the Yellow Sea and its adjacent area. Among the earthquakes, the number of earthquakes with M≥5.0 is 209, and at least 43 of the earthquakes caused serious losses, 20 of the earthquakes caused human causalities. It is demonstrated that there were 3 areas of historical earthquake concentration and the earthquake activity was higher in the 16th century and the first half if the 20th century.展开更多
The paper shows the approach toward the calculation of one of the bigger PFRP (Pultruded Fiber Reinforced Polymer) structure realized in high seismic zone, i.e., a covering structure of an historic church stroked an...The paper shows the approach toward the calculation of one of the bigger PFRP (Pultruded Fiber Reinforced Polymer) structure realized in high seismic zone, i.e., a covering structure of an historic church stroked and partially collapsed by earthquake in L'Aquila (Italy), the 4 April 2009. The goal regards the analysis and evaluation of seismic performance of that structure made by very light and elastic-brittle material, as FRP material, in a moment in which there is a loss of technical recommendation for specific calculation in seismic field, indeed actually some deepening already present in literature allows only static field. The covering structure is an all FRP spatial-reticular with elements made by pultrusion process, connection plates by bag molding process and steel bolts. The PFRP structure covers more than 1000 meters squares surface with 32 meters height and only 100 kN weight. Detail performance of first part of PFRP structure through mode vibrations and involved percentage mass deduced by numerical approach with discussion of employment's perspectives of PFRP material in seismic zones than traditional material are showed.展开更多
文摘As a result of sorting out, estimating and cataloging of historical earthquakes, from the year of 2 A.D. to Aug., 1949, we found that there were 2187 earthquakes with M≥3.0 in the area of the Yellow Sea and its adjacent area. Among the earthquakes, the number of earthquakes with M≥5.0 is 209, and at least 43 of the earthquakes caused serious losses, 20 of the earthquakes caused human causalities. It is demonstrated that there were 3 areas of historical earthquake concentration and the earthquake activity was higher in the 16th century and the first half if the 20th century.
文摘The paper shows the approach toward the calculation of one of the bigger PFRP (Pultruded Fiber Reinforced Polymer) structure realized in high seismic zone, i.e., a covering structure of an historic church stroked and partially collapsed by earthquake in L'Aquila (Italy), the 4 April 2009. The goal regards the analysis and evaluation of seismic performance of that structure made by very light and elastic-brittle material, as FRP material, in a moment in which there is a loss of technical recommendation for specific calculation in seismic field, indeed actually some deepening already present in literature allows only static field. The covering structure is an all FRP spatial-reticular with elements made by pultrusion process, connection plates by bag molding process and steel bolts. The PFRP structure covers more than 1000 meters squares surface with 32 meters height and only 100 kN weight. Detail performance of first part of PFRP structure through mode vibrations and involved percentage mass deduced by numerical approach with discussion of employment's perspectives of PFRP material in seismic zones than traditional material are showed.