The most important method of understanding liquefaction-induced engineering failures comes from the investigation and analysis of earthquake damage.In May 2021,the Maduo M_(s)7.4 earthquake occurred on the Tibetan Pla...The most important method of understanding liquefaction-induced engineering failures comes from the investigation and analysis of earthquake damage.In May 2021,the Maduo M_(s)7.4 earthquake occurred on the Tibetan Plateau of China.The most representative engineering disaster caused by this earthquake was bridge damage on liquefied sites.In this study,the mutual relationships between the anti-liquefaction pre-design situation,the ground motion intensity,the site liquefaction severity,and the bridge damage state for this earthquake were systematically analyzed for typical bridge damage on the liquefied sites.Using field survey data and the current Chinese industry code,simulations of the liquefaction scenarios at typical bridge sites were performed for the pre-design seismic ground motion before the earthquake and the seismic ground motion during the earthquake.By combining these results with post-earthquake investigation results,the reason for the serious bridge damage resulting from this earthquake is revealed,and the necessary conditions for avoiding serious seismic damage to bridges built in liquefiable sites is presented.展开更多
The May 222021 M_(W)7.4 Madoi,Qinghai,China earthquake presented a rare opportunity to apply the modern unmanned aerial vehicle(UAV)photography method in extreme altitude and weather conditions to image surface ruptur...The May 222021 M_(W)7.4 Madoi,Qinghai,China earthquake presented a rare opportunity to apply the modern unmanned aerial vehicle(UAV)photography method in extreme altitude and weather conditions to image surface ruptures and near-field effects of earthquake-related surface deformations in the remote Tibet.High-resolution aerial photographs were acquired in the days immediately following the mainshock.The complex surface rupture patterns associated with this event were covered comprehensively at 3-6 cm resolution.This effort represents the first time that an earthquake rupture in the interior of the Qinghai-Tibetan Plateau has been fully and systematically captured by such high-resolution imagery,with an unprecedented level of detail,over its entire length.The dataset has proven valuable in documenting subtle and transient rupture features,such as the significant mole-tracks and opening fissures,which were ubiquitous coseismically but degraded during the subsequent summer storm season.Such high-quality imagery also helps to document with high fidelity the fractures of the surface rupture zone(supplements of this paper),the pattern related to how the faults ruptured to the ground surface,and the distribution of off-fault damage.In combination with other ground-based mapping efforts,the data will be analyzed in the following months to better understand the mechanics of earthquake rupture related to the fault zone rheology,rupture dynamics,and frictional properties along with the fault interface.展开更多
基金Natural Science Foundation of Heilongjiang Province under Grant No.ZD2019E009Key Project of National Natural Science Foundation of China under Grant No.U1939209。
文摘The most important method of understanding liquefaction-induced engineering failures comes from the investigation and analysis of earthquake damage.In May 2021,the Maduo M_(s)7.4 earthquake occurred on the Tibetan Plateau of China.The most representative engineering disaster caused by this earthquake was bridge damage on liquefied sites.In this study,the mutual relationships between the anti-liquefaction pre-design situation,the ground motion intensity,the site liquefaction severity,and the bridge damage state for this earthquake were systematically analyzed for typical bridge damage on the liquefied sites.Using field survey data and the current Chinese industry code,simulations of the liquefaction scenarios at typical bridge sites were performed for the pre-design seismic ground motion before the earthquake and the seismic ground motion during the earthquake.By combining these results with post-earthquake investigation results,the reason for the serious bridge damage resulting from this earthquake is revealed,and the necessary conditions for avoiding serious seismic damage to bridges built in liquefiable sites is presented.
基金This work was supported by the National Natural Science Foundation of China(U1839203,42011540385)the National Key Laboratory of Earthquake Dynamics(LED2020B03,IGCEA1812)the Science and Technology Projects of Qinghai Province(2020-ZJ-752).
文摘The May 222021 M_(W)7.4 Madoi,Qinghai,China earthquake presented a rare opportunity to apply the modern unmanned aerial vehicle(UAV)photography method in extreme altitude and weather conditions to image surface ruptures and near-field effects of earthquake-related surface deformations in the remote Tibet.High-resolution aerial photographs were acquired in the days immediately following the mainshock.The complex surface rupture patterns associated with this event were covered comprehensively at 3-6 cm resolution.This effort represents the first time that an earthquake rupture in the interior of the Qinghai-Tibetan Plateau has been fully and systematically captured by such high-resolution imagery,with an unprecedented level of detail,over its entire length.The dataset has proven valuable in documenting subtle and transient rupture features,such as the significant mole-tracks and opening fissures,which were ubiquitous coseismically but degraded during the subsequent summer storm season.Such high-quality imagery also helps to document with high fidelity the fractures of the surface rupture zone(supplements of this paper),the pattern related to how the faults ruptured to the ground surface,and the distribution of off-fault damage.In combination with other ground-based mapping efforts,the data will be analyzed in the following months to better understand the mechanics of earthquake rupture related to the fault zone rheology,rupture dynamics,and frictional properties along with the fault interface.
