The current design approach recommended by seismic codes is often based on the use of uniform-hazard response spectra, reduced to account for inelastic structural behaviour. This approach has some strong limitations that have been highlighted in many studies, including not allowing a direct control of the seismic risk and losses. This study aims at quantifying the levels of safety and the costs associated with this design approach, and to investigate alternative design approaches that have been developed in the last decades. In particular, a risk-targeting approach and a minimum-cost approach are considered. The first one, allowed by US codes, aims at designing structures with the same risk of collapse throughout regions of different seismicity. The second one aims to minimize the sum of the initial construction cost and the cost of expected losses due to future earthquakes. The comparison of the three approaches is performed by considering, as an example structure, a four-storey reinforced concrete frame building located in different areas in Europe, and by looking at the implications in terms of achieved safety levels, initial costs, and future losses. The study’s results provide useful information on how the design criteria and the different hazard levels throughout Europe affect the cost and safety levels of seismic design.

中文翻译：

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评估结构抗震设计的替代方法

地震规范建议的当前设计方法通常基于均匀危害响应谱的使用，并减少以考虑非弹性结构行为。这种方法有一些强大的局限性，许多研究已经强调了这些局限性，包括不允许直接控制地震风险和损失。这项研究旨在量化与该设计方法相关的安全级别和成本，并研究近几十年来开发的替代设计方法。特别是考虑了以风险为目标的方法和最低成本的方法。美国规范允许的第一个结构旨在设计在不同地震活动性区域中具有相同坍塌风险的结构。第二个目的是使初始建设成本和未来地震造成的预期损失成本之和最小。三种方法的比较是通过考虑一个位于欧洲不同地区的四层钢筋混凝土框架结构作为示例结构，并从已实现的安全水平，初始成本和未来损失的角度考虑的。这项研究的结果提供了有用的信息，说明了整个欧洲的设计标准和不同的危害等级如何影响抗震设计的成本和安全等级。并从已实现的安全水平，初始成本和未来损失的角度研究其含义。这项研究的结果提供了有用的信息，说明了整个欧洲的设计标准和不同的危害等级如何影响抗震设计的成本和安全等级。并从已实现的安全水平，初始成本和未来损失的角度研究其含义。这项研究的结果提供了有用的信息，说明了整个欧洲的设计标准和不同的危害等级如何影响抗震设计的成本和安全等级。