Slope Seismic Stability
The seismic stability of slopes has been the hot spot issues of geological disaster study, and especially after the 5.12 Wenchuan earthquake, it has become the study focus of specialists and scholars. For slope seismic stability analysis, the current meth
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Slope Seismic Stability
The seismic stability of slopes has been the hot spot issues of geological disaster study, and especially after the 5.12 Wenchuan earthquake, it has become the study focus of specialists and scholars. For slope seismic stability analysis, the current method includes pseudo-static method, sliding block analysis method, and numerical simulation, in which pseudo-static method only takes consideration of the influence of PGA on slope stability, but not the influence of frequency and duration of seismic waves; neither sliding block analysis method can solve the instant stability coefficient of slopes under seismic loading effects, nor can it accurately evaluate the seismic stability in real engineering, so it is not convenient to use; although numerical simulation can carry out time–frequency analysis of rock slope stability under seismic effects, the operation is complex, especially for high and steep slopes with large difference in rock layer distribution. However, the results of Chap. 6 show that bedrock and overburden slopes coming across landslides are induced by duration, frequency, and amplitude of seismic ground motion, and these three form an organic whole, so singly considering one of them will lead to partial recognition of slope seismic stability. Therefore, it is quite necessary to study the influence of time, frequency, and amplitude on slope seismic stability time–frequency analysis. According to the field research results and formation mechanism analysis results of large-scale landslide disasters in Wenchuan earthquake, it can be known that SV wave (elastic wave whose vibration direction and propagation direction are vertical to the slope cross section) is the most disastrous and causes the most serious damage. In addition, the major energy of seismic wave is controlled by SV wave, while the duration of P wave is short and its energy is small. Therefore, we can approximately take it that the slope stability under earthquake is the slope stability under SV wave. But SV wave is a complex non-stationary signal, whose frequency feature changes with time. At the same time, bedrock and overburden slope are the most common slope structure with maximum instability quantity in seismic areas. Therefore, this chapter will focus on bedrock and overburden slope, based on elastic wave theory, adopt Hilbert–Huang transform and general analysis model of slopes, © Science Press and Springer Science+Business Media Singapore 2017 Y. Changwei et al., Slope Earthquake Stability, DOI 10.1007/978-981-10-2380-4_7
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7 Slope Seismic Stability
and propose time–frequency analysis method of bedrock and overburden slope seismic stability which could take consideration of three factors of seismic waves so as to provide new ideas to bedrock and overburden slope stability recognition.
7.1
Slope Seismic Stability
Based on elastic wave theory and general geological analysis model, we adopt Hilbert–Huang transform, propose time–frequency analysis method of bedrock and overburden slope seismic stability,
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