traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to...traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration （PGA） is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.展开更多
The authors make the analysis of first arrivals of the P-wave from Ina-TEWS （Indonesian tsunami early warning system） and CTBT （comprehensive nuclear-test-band treaty） stations. These are used for earthquake early...The authors make the analysis of first arrivals of the P-wave from Ina-TEWS （Indonesian tsunami early warning system） and CTBT （comprehensive nuclear-test-band treaty） stations. These are used for earthquake early warning, magnitude determination and potential earthquake hazard mitigation based on seismogram acceleration. This research is focused on the study of energy duration of high frequency, and the maximum displacement of P-waves by observing broadband seismograms. The further analysis consists of deconvolution, integration or defferentiation, recursive filtering for data restitution, and applying a Butterworth filter of second order. The Butterworth filter uses high frequency 0.075 Hz to cut the effect of drift, and band-pass frequency 2-4 Hz for use in magnitude calculation. The authors choose potentially damaging earthquakes to be greater than Mw 〉 6.0. Based on the trigger on the three seconds the first arrival P-wave, the dominant period （Td） and amplitude displacement （Pd） was calculated by using data CISI （Indonesian CI Sompet） seismological station, Garut （west Java） and tested for data CTBT, LEM bang, Bandung （LEM station）. This research resulted determination of the P-wave arrival time accurately using integrated skewness and kurtosis. Performance data from the CTBT stations is very high. Signal to noise ratio 〉1,000 after passing through the filter. Such riset conducted to find out a rapid magnitude estimations from predominant frequency of displacement are： log Td = 0.2406 M- 1.3665 （R = 0.73） or M = 4.156 log Td ＋ 5.6797. Relationship of Pd, magnitude moment, Mw and hypocentre, R are log Pd = -4.684 ＋ 0.815 Mw - 1.36 log R. For relation of PGA （peak ground acceleration） and amplitude displacement are log PGA = 1.117 log Pd ＋ 0.728 （R = 0.91）. Furthermore, this formula can be used to support earthquake early warning in west of Java.展开更多
基金supported in part by National Science Foundation of China (Contract NO. 41030742)Guangxi Science Foundation and the Program for Science & Technology of Henan Province in China (Grant No. 142300410200)
文摘traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration （PGA） is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.
文摘The authors make the analysis of first arrivals of the P-wave from Ina-TEWS （Indonesian tsunami early warning system） and CTBT （comprehensive nuclear-test-band treaty） stations. These are used for earthquake early warning, magnitude determination and potential earthquake hazard mitigation based on seismogram acceleration. This research is focused on the study of energy duration of high frequency, and the maximum displacement of P-waves by observing broadband seismograms. The further analysis consists of deconvolution, integration or defferentiation, recursive filtering for data restitution, and applying a Butterworth filter of second order. The Butterworth filter uses high frequency 0.075 Hz to cut the effect of drift, and band-pass frequency 2-4 Hz for use in magnitude calculation. The authors choose potentially damaging earthquakes to be greater than Mw 〉 6.0. Based on the trigger on the three seconds the first arrival P-wave, the dominant period （Td） and amplitude displacement （Pd） was calculated by using data CISI （Indonesian CI Sompet） seismological station, Garut （west Java） and tested for data CTBT, LEM bang, Bandung （LEM station）. This research resulted determination of the P-wave arrival time accurately using integrated skewness and kurtosis. Performance data from the CTBT stations is very high. Signal to noise ratio 〉1,000 after passing through the filter. Such riset conducted to find out a rapid magnitude estimations from predominant frequency of displacement are： log Td = 0.2406 M- 1.3665 （R = 0.73） or M = 4.156 log Td ＋ 5.6797. Relationship of Pd, magnitude moment, Mw and hypocentre, R are log Pd = -4.684 ＋ 0.815 Mw - 1.36 log R. For relation of PGA （peak ground acceleration） and amplitude displacement are log PGA = 1.117 log Pd ＋ 0.728 （R = 0.91）. Furthermore, this formula can be used to support earthquake early warning in west of Java.
