由于过度依赖于对局部场地条件的估计，在近几十年的研究及发展中，人工地震动生成始终面临着两大问题：第一，与场地上目标结构物的动力特性完全脱节；第二，基于场地条件估计而生成的人工地震动时程具有任意性，与将来实际发生的天然随机地震动往往相去甚远。为了解决上述问题，转变单纯以场地为核心的人工地震动生成理念，本项目以目标结构物为核心，以期建立一种与目标结构物动力特性相容的包络性人工地震动生成模型，该模型针对目标功率谱模型中前N阶优势时频分量的能量分布密度、结构动力响应目标包线函数的设计、目标响应与地震动输入时程的反演等一系列关键问题开展相关研究。尽管仍然不能准确估计场地上可能发生的天然地震动的精确形式，但该方法生成的人工地震动时程具有包络性，能在主动、合理、可控的概率范围内保证结构的安全，从而为今后的抗震研究提供一种更为安全、有效的新型人工地震动生成模式。

Due to overdependence on the estimation of local site conditions, in the recent decades of research and development, the generation of artificial ground motion is always faced with two major problems: first, it is completely disjointed with the dynamic characteristics of the target structure on the site; second, the time history of artificial ground motion generated by site condition estimation is arbitrary, which is far from the natural random ground motion that actually occurs in the future. In order to solve the above problems and transform the concept of artificial ground vibration at the core of the field, the project is centered on the target structure. In order to establish an enveloping artificial ground motion model which is compatible with the dynamic characteristics of the target structure, this project has carried out a series of research on key issues, for example, the energy distribution density of the predominant frequency component of the front N order in the target power spectrum model, the design of the target packet line function of the structural dynamic response, the target response inversion of input time history of ground motion, etc. Although the exact form of natural earthquake may not be accurately estimated on the site, the artificial seismic time history generated by this method is enveloped, and it can ensure the safety of the structure in the probability range of active, reasonable and controllable. Thus, it provides a more safe and effective model of artificial ground motion for the future research on earthquake resistance.