论文部分内容阅读
地震动是个动态随机过程,而传统岩石边坡地震可靠性分析往往基于拟静力法,忽略了地震的随机性。现有基于数值分析软件的地震响应功率谱法虽可考虑地震随机特征,却相对费时费力。提出一种岩石边坡随机地震响应及动力可靠度分析方法。首先,运用虚拟激励法建立了岩石边坡随机地震响应的快速计算方法。根据响应计算结果,基于首次穿越破坏准则建立了岩石边坡动力可靠度计算方法。算例分析表明,本文随机地震响应快速计算方法简便可行,且具有较高的计算精度。本文动力可靠度计算方法低估了边坡的地震可靠性,能更真实地反映边坡在地震中的实际安全情况。地震作用下边坡可靠性受地震设防烈度、场地类别和地震时间的影响。而对于传统拟静力法,地震力仅根据设防烈度确定。因此,当对于不同的场地类别和地震时间时,本文动力可靠度计算法将更具优越性。
Earthquake is a dynamic random process. However, the seismic reliability analysis of traditional rock slopes is often based on quasi-static method, ignoring the randomness of earthquakes. However, the existing seismic response power spectrum method based on numerical analysis software can take seismic random characteristics into consideration, but it is relatively time-consuming and labor-intensive. A method of random seismic response and dynamic reliability analysis of rock slope is proposed. First, a fast method of calculating random seismic response of rock slope is established by using virtual excitation method. Based on the response calculation results, a method to calculate the dynamic reliability of rock slope is established based on the first crossing failure criterion. The case study shows that the method of random seismic response in this paper is simple and feasible, and has a high computational accuracy. The dynamic reliability calculation method in this paper underestimates the seismic reliability of the slope and can more accurately reflect the actual safety of the slope in the earthquake. The reliability of the slope under earthquake is affected by the seismic fortification intensity, the type of site and the time of the earthquake. For the traditional quasi-static method, the seismic force is only determined according to the fortification intensity. Therefore, the dynamic reliability calculation method in this paper will have more advantages when it comes to different site types and seismic times.