Performance Based Seismic Evaluation of Underground Structures

0000136 Ramirez日本科比的大海车站是第一个没有穿越活动断层的地下结构，在地震中倒塌。 初步分析和其他人的分析表明，中间柱严重不足以抵抗侧向变形。 然而，Daikai的失败只是一个警告。 在科比地震中观察到的大量地下结构损坏甚至完全倒塌的例子有助于确定一个值得认真研究的问题。 值得关注的是，在美国和日本，可能有类似于大海站条件下的地下结构。 这个问题是多方面的，因为它需要开发的方法来进行现有的地下结构的地震风险评估以及新的设计，给定适当的地面运动特性。 这就要求不仅从安全性方面，而且从可使用性方面明确定义结构性能。 该研究项目的目标是：识别和评估地震事件期间地面与结构之间的荷载传递机制，（2）确定钢筋混凝土构件在非弹性位移循环期间的变形能力，（三）明挖法地下结构抗震性能的新技术和标准的发展以及累积损伤关键要素的识别明挖回填地下结构的评估。本项目的研究团队包括来自美国和日本的结构和岩土工程师，他们来自学术界和实践界。本项目得到了NSF 98-36第三年竞赛的支持。“美日城市地震减灾合作研究。"

0000136RamirezThe Daikai Station Kobe, Japan was the first underground structure not crossing an active fault the collapsed during an earthquake. Preliminary analysis and that of others have indicated that the middle column was grossly inadequate to resist lateral deformations. However, the Daikai failure is only a warning. The numerous examples of damage and even complete collapse of underground structures observed during the Kobe Earthquake help define a problem that merits serious investigation. Of great concern is that there may be in the USA and Japan, underground structures under similar conditions to the Daikai Station. The problem is multifaceted in that it requires that approaches be developed to both conduct the earthquake risk assessment of existing underground structures as well as the design of new ones, given the appropriate ground motion characteristics. This calls for clearly defining structural performance not only in terms of safety, but serviceability as well. The objectives of this research project are: Identification and evaluation of the load-transfer mechanisms between the ground and the structure during a seismic event, (2) Determination of the deformation capacity of reinforced concrete members during inelastic cycles of displacement, (3) Development of new techniques and criteria for seismic performance of cut and cover underground structures and identification of critical elements for cumulative damage assessment of cut and cover underground structures.The research team in this project includes USA and Japan based structural and geotechnical engineers from both academia and practice.This project is supported under the 3rd-year competition under NSF 98-36. "US Japan Cooperative Research in Urban Earthquake Disaster Mitigation."