Vertical Evacuation Structures Subjected to Sequential Earthquake and Tsunami Loadings

承受连续地震和海啸荷载的垂直疏散结构

• 批准号: 1726326
• 负责人: Dawn Lehman
• 金额: $ 100.75万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-15 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1726326&HistoricalAwards=false
• 关键词: Vertical; Evacuation; Structures; Subjected; Sequential

In extreme events, such as major earthquakes or tsunamis, public safety is a primary concern. A major subduction zone earthquake could cause a large tsunami, which could render constructed infrastructure near the coastline, traditionally designed for only seismic loads, to be severely damaged and result in loss of life. In coastal regions at low elevations, it may be difficult to quickly move to higher ground in the short time between the initial ground shaking and the arrival of a tsunami from a subduction earthquake. However, a vertical evacuation structure (VES) could provide refuge, with the most promising VES for large coastal populations being buildings with lower stories capable of resisting the sequential earthquake demands and tsunami loads. This research will investigate a new structural system for a building to serve as a VES, where the structural elements are continuous from the end of the pile to the top of the structure. This new system will use the above-wave-height stories for evacuation; the lower (below wave) stories will use connections that allow walls and slabs of the lower, non-evacuation floors to "breakaway" at the highest water level. Although counterintuitive, this breakaway system will reduce the tsunami load demands on the structure, further protecting the building and its occupants. This research will investigate the interactions of the structure, soil, and tsunami waves for both traditional systems designed only for seismic loads and the new breakaway structural system. The results of this research will provide first-of-its kind data for this new type of VES, which can improve life safety in tsunami-prone regions and provide course-ready material for graduate-level classes and seminars for researchers and practitioners. Data from the project will be archived and made publicly available in the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) Data Depot (http://www.designsafe-ci.org). Although evacuation structures have been built in tsunami-prone regions in Japan and the United States, they are typically low-rise structures with limited shelter capacity. In contrast, taller structures could serve dual purposes, such as a hotel with lower stories housing retail or conference rooms, with upper levels designed for evacuation. Under earthquake loading, buildings are expected sustain damage in the maximum credible event and, unless specific to the site, soil-structure interaction is neglected. This design philosophy would not serve for a VES, which must be designed to: (1) remain damage-free during the maximum credible earthquake, (2) sustain the maximum considered tsunami at the lower floors, including horizontal and vertical forces, where initial research shows that these tsunami force demands can be two to five times the design earthquake forces, and (3) account for changes in the stiffness and strength of the soil due to liquefaction and scour. This research will address the fundamentals of sequential earthquake and tsunami hazard building performance to serve as a VES, accounting for full nonlinear soil-structure-wave interaction. Two structural systems will be studied: exterior concrete walls, which are a traditional structural solution for seismic loads, and a new structural system utilizing continuous concrete filled tube pile-column frames with breakaway connections at the floors below the inundation depth, tuned to fracture at specific loading resulting from hydrostatic buoyancy. The research activities will involve the following: (1) investigate fundamental characteristics of the soil-structure system through computational simulation, (2) experimentally study tsunami demands on the structure using the NHERI Large Wave Flume at Oregon State University, (3) analytically couple the tsunami demand and structure-soil response analyses using the NHERI Computational Modeling and Simulation Center resources, and (4) combine the findings to evaluate current and establish new design methodologies for VESs subjected to sequential earthquake and tsunami hazard loading.

在大地震或海啸等极端事件中，公共安全是首要问题。 俯冲带大地震可能引起大规模海啸，这可能使传统上仅为地震荷载设计的海岸线附近的建筑基础设施受到严重破坏，并导致生命损失。在低海拔的沿海地区，可能很难在最初的地面震动和俯冲地震海啸到来之间的短时间内迅速转移到高地。 然而，垂直疏散结构（VES）可以提供避难所，最有前途的VES为大型沿海人口的建筑物具有较低的楼层能够抵抗连续的地震需求和海啸载荷。本研究将探讨一种新的结构体系的建筑物，作为一个VES，其中的结构元件是连续的，从端部的桩的结构的顶部。这个新系统将使用高于波浪高度的楼层进行疏散;较低（低于波浪）的楼层将使用连接，允许较低的非疏散楼层的墙壁和楼板在最高水位处“脱离”。虽然违反直觉，但这种分离系统将减少海啸对结构的负载需求，进一步保护建筑物及其居住者。 本研究将探讨结构，土壤和海啸波的相互作用的传统系统设计的地震荷载和新的分离结构系统。 这项研究的结果将为这种新型的VES提供首个同类数据，它可以提高海啸易发地区的生命安全，并为研究人员和从业人员的研究生课程和研讨会提供课程准备材料。该项目的数据将在NSF支持的自然灾害工程研究基础设施（NHERI）数据库（http：//www.example.com）中存档并公开提供。www.designsafe-ci.org 虽然在日本和美国的海啸易发地区已经建造了疏散结构，但它们通常是低层结构，避难能力有限。 相比之下，较高的建筑物可以达到双重目的，例如酒店的较低楼层可以容纳零售或会议室，而上层则设计用于疏散。在地震荷载作用下，预计建筑物将在最大可信事件中遭受破坏，除非特定于场地，否则土-结构相互作用将被忽略。这一设计理念不适用于VES，VES的设计必须：（1）在最大可信地震期间保持无损坏，（2）在较低楼层承受最大考虑海啸，包括水平和垂直力，其中初步研究表明这些海啸力需求可能是设计地震力的2至5倍，（3）考虑了由于液化和冲刷引起的土壤刚度和强度的变化。这项研究将解决的基本原理，连续地震和海啸灾害的建筑物的性能，作为一个VES，占全非线性土壤结构波相互作用。将研究两种结构系统：外部混凝土墙，这是一种传统的地震荷载结构解决方案，以及一种新的结构系统，利用连续混凝土填充管桩柱框架，在淹没深度以下的楼层具有分离连接，在静水浮力产生的特定载荷下调整断裂。研究活动将涉及以下方面：（1）通过计算模拟研究土壤-结构系统的基本特性，（2）使用俄勒冈州州立大学的NHERI大型波浪水槽实验研究海啸对结构的需求，（3）使用NHERI计算建模和模拟中心的资源分析耦合海啸需求和结构-土壤响应分析，（4）结合联合收割机的研究结果，对承受连续地震和海啸灾害荷载的VES的现有设计方法进行评估，并建立新的设计方法。

项目成果

1.45m wave

1.45m波

• DOI: 10.17603/ds2-x0yd-w493
• 发表时间: 2022
• 期刊: Designsafe-CI
• 作者: Pyke, Christopher

1.4m Wave

1.4m波

• DOI: 10.17603/ds2-2vwe-tz62
• 发表时间: 2022
• 期刊: Designsafe-CI
• 作者: Pyke, Christopher

Modeling recommendations for RC and CFST sections in LS-Dyna including bond slip

• DOI: 10.1016/j.engstruct.2020.111612
• 发表时间: 2021-02
• 期刊: Engineering Structures
• 影响因子: 5.5
• 作者: Mu-Zi Zhao;D. Lehman;C. Roeder

Integrated Study of Existing Tsunami Design Standards

现有海啸设计标准的综合研究

• DOI: 10.1061/(asce)st.1943-541x.0003506
• 发表时间: 2022
• 期刊: Journal of Structural Engineering
• 影响因子: 4.1
• 作者: Lewis, Nicolette S.;Lehman, Dawn E.;Motley, Michael R.;Arduino, Pedro;Roeder, Charles W.;Pyke, Christopher N.;Sullivan, Kenneth P.
• 通讯作者: Sullivan, Kenneth P.