| Seismic stability of slope is one of hot problems in geotechnical seismicengineering and earthquake engineering field. Studies show that there areegregious coherence between the distribution of global earthquake belts andlandslide belts, which sufficiently reflects the effects of earthquake inducing onslope stability losing. That complexity of the composition of geological materialsconstitutive models and speciality of earthquake ground motion with strongrandomicity make slope seismic stability difficult. Some primary studies, aimedat seismic stability of rock slope under earthquake ground motion are carried on.The main studies are as follows:1. The state-of-the-art advancement of several important problems onseismic stability analysis of rock-soil slopes is reviewed, including analysismethod of seismic response, dynamic properties, strength criteria, parametertesting, failure mechanism& failure location, seismic stability evaluation methods,seismic stability evaluation index &safety standard, earthquake input andcomputation accuracy of seismic stability evaluation index, and concise remarksare made. Then some study problems, which need to be done in future, aresuggested.2. Considering obvious weak slip zone occurring within rock slope, thedifferent slip zone analysis methods during the calculation of finite element arebrought forward and the method combining the finite element method with limitequilibrium method used in engineering is presented. The method proposedpresent initial static stress field and safety factor for seismic stability analysis ofrock slope. The method is used to calculate one rock slope. On the basis of this,the effects of material parameters on safety factor of rock slope are studied.3. The analysis method truly reflecting characters of earthquake groundmotion transmitting is the basis of concisely describing seismic response ofrock-mass. A new method, explicit wave motion fem, with considering theElastic-viscoplastic dynamic properties of rock-mass, is proposed, and itscomputation theories and details, including constitute model ofelastic-viscoplastic of rock, step-by-step formula of displacement, execution ofmulti-transform formula with both different height, are expounded, then programare coded. As a case of simple rock slope, its seismic responses under onedisplacement pulse and true earthquake record input are analyzed, and thecorrectness of program is verified.4. The calculation method of dynamic safety factor time history of rockslope is present, and based on it, the concept of dynamic safety factor of rockslope is proposed introducing the idea of reliability theory. The computationmethod of dynamic safety factor of rock slope is proposed. It is used to calculateone rock slope, compared with that of pseudo-static method.5. The effects of input ground motion peak and frequency content onstability of rock slope are studied. Then, the relations of pseudo-static safetyfactor and dynamic safety factor of rock slope, input ground motion peak anddynamic safety factor of rock slope are given, which provides a feasible methodfor predicting seismic stability of important rock slopes. In addition the effects ofvertical input ground motion on stability of rock slope are studied.6. The stability of high and steep slope along leading road along DaduheRiver's Ya'an bank Country Road No. 108 directly decides natural running of theroad and Daduhe bridge in Shimian. Based on comprehensively analyzing theregion earthquake seismic activity, earthquake geological structures, potentialearthquake source in the slope region are acquired, and acceleration peak andtarget spectra of the slope site, whose probability of exceedance is 10% in 50years, are computed. Based on these, 3 pieces of man made earthquake waves aregenerated by triangle progression. As the inputs of generated waves, the seismicstability of high and steep slope along, lying at leading road along DaduheRiver's Ya'an bank Country Road No. 108 is computed, using the method ofdynamic safety factor of rock slope.
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