Qi Shengwen et al.-EG: The test confirmed that there were two types of power earthquake response in one-sided slope

Earthquake landslide is a secondary disaster induced by earthquakes. It often causes heavy casualties and huge property losses. The law of the power response of the slope is the key to evaluate the stability of the slope earthquake, engineering rock body earthquake resistance, and prediction of earthquake landslide. Essence Many post -earthquake surveys and trials have also found that there are obvious seismic amplification phenomena on the top of the slope, which is an important reason for the loss of stability of the slope. However, there are many factors that affect the power response of the slope, mainly including the characteristics of the source of the earthquake, the path of communication, and the characteristics of the venue. It involves multi -disciplines such as rock and soil dynamics, earth physics and other disciplines, which are extremely complicated. Facial (Figure 1), the analysis method is incomparable, and it is difficult to obtain the law of response, which leads to the stability evaluation of the slope seismic is still one of the most challenging problems in the construction of major projects in the activity structure area.

Figure 1 Double -sided slope (A) and single -sided slope (B)

In response to the above -mentioned important issues, Researcher Qi Shengwen, Institute of Geology and Earth Physics of the Chinese Academy of Sciences, carried out a large -scale slope vibration platform physical simulation and in -situ test based on similar theories on the basis of existing research. The test results show that the single -sided slope earthquake dynamic response form has obvious frequency dependence. When the loading frequency is less than a certain boundary value, the slope acceleration amplification coefficient increases with the increase in loading frequency, and the slope acceleration amplification coefficients are followed by the slope surface acceleration coefficient. The increase of the slope height increases and increases; when the loading frequency is greater than the critical value, the acceleration factor of the slope surface will decrease, and the slope acceleration amplification coefficient will be decreased before the slope height increases (Figure 2, 3) Essence The test results further confirmed the discovery of the Qi et al (2003) and QI (2006): that is, there is a high -side slope dynamic response and low -side slope power response form, not just the slope power amplification of the slope of the previous generation Phenomenon.

Figure 2 (A) Vibration table test and numerical simulation acceleration timing curve; (b) acceleration local amplification diagram; (C) slope PGA amplification coefficient

Figure 3 The distribution of the slope acceleration zoom in the slope under different frequencies. (A) The frequency of loading is 15Hz; (b) the loading frequency is 30Hz; (C) the loading frequency is 45Hz; (D) the loading frequency is 60Hz

On this basis, the author uses physical simulation as a constraint, and the nuclear numerical simulation of the school (Figure 2) has carried out a large number of numerical tests to study the physical mechanics parameters (density, elastic modulus, etc.), slope height, slope slope, slope slope, and slopes. The effects of factor such as slope, input earthquake dynamic frequency and other factors on the slope earthquake response, and found that the critical countless outline of the single -sided slope power response is about 0.17 ～ 0.20 -0.2, the slope shoulder acceleration amplification coefficient increases with the increase of H/λ; when the H/λ & 0.17-0.2, the slope shoulder acceleration zero will decrease with the increase of H/λ, and it should be should be used as it should be should be should be should be should be used as it should be should be used as should be should be should be used as a should be. At H/λ & 0.4, the sloping shoulder acceleration zero -amplification coefficient will be less than 1.0, that is, the decaying effect of the slope earthquake response will occur. At the same time, for a specific slope height, the slope acceleration amplification coefficient increases with the increase of the slope (Figure 4). Finally, based on the theory of earthquake wave transmission, the author explained that the high -side slope power response (H/λ & 0.2) and low -side sloping power response (H/λ≤0.2) were significantly different in the formation of the mass point vibration mode.

Figure 4 The acceleration enlargement coefficient (slope H = 60 m) and comparison with predecessors (Ashford et al., 1997), BP (Bouckovalas and Papadimitriou, 2005), (Tripe et al., 2013))

This study confirmed from the perspective of the test that for a given seismic input, the single -sided sloping power response has two types: high -side sloping power response and low -side sloping power response, and the critical countless outline high H/λ is about 0.20 is about 0.20 At the same time, when the high H/λ is about 0.40, the slope power response is no longer dominated by the amplification effect, but the attenuation effect dominance. This parameter provides an appropriate indicator for quantitative research on sloping power response, and can also provide important references for the stability evaluation of slope power stability.

研究成果发表于工程地质领域国际学术期刊Engineering Geology （祁生文*，贺建先，詹志发. A single surface slope effects on seismic response based on shaking table test and numerical simulation [J]. Engineering Geology, 2022, 306: 106762. DOI : 10.1016/j.enggeo.2022.106762). Studies have been funded by projects such as the National Natural Science Science Outstanding Youth Fund Project (41825018) and the Second Qinghai -Tibet Plateau Comprehensive Scientific Investigation Studies (QZKK20190904) and other projects.

Beautiful editor: Chen Feifei

School pair: Wanpeng

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