Seismic protection of Heritage structures through Vibrating Barriers

地震多发区的历史建筑极易受到破坏。主要原因是这些建筑物的设计不足以抵御地震，而且建筑材料会随着时间的推移而变质。最近的地震，如2016年的诺尔恰地震，就是一个明显的例子，表明有必要迅速采取行动，保护遗产结构免受此类自然灾害的影响。文物建筑的抗震保护是一个尚未解决的研究问题，它不仅是一个公共安全问题，也增加了对文物建筑艺术价值保护的限制。在这方面，有一个明显的知识差距，导致研究问题，它是如何可能保护结构，而不修改它。以前的研究表明，保护结构的地震作用是管理使用本地化的解决方案，如隔离器和阻尼器。研究还表明，一个主要原因是，在现有结构中引入控制装置侵入性太强，成本太高，需要拆除一些结构和/或非结构部件。对于遗产结构，显然不能应用这些技术，因此目前没有采取地震保护行动来保护这些艺术珍品。研究还没有检查非侵入性设备保护遗产结构的潜力。拟议的研究将首次调查使用新型振动屏障（ViBa）来减少遗产结构的地震振动。振动屏障（Vibrating Barrier，简称ViBa）是一种位于土壤中的大型结构，通过结构-土壤-结构相互作用机制来减少邻近结构的振动。由于ViBa与结构分离，因此它特别适合于遗产结构，以便完全保留其原始结构而不进行任何更改。拟议的研究将旨在通过一个测试ViBa作用和未知设计参数的项目，建立一种保护遗产结构的通用方法。技术细节将通过文化合作伙伴推荐的案例研究来制定。特别是ViBa的设计首先需要通过有限元方法对遗产结构和下面的土壤进行数值建模。在这方面，文化合作伙伴将提供数据，以建立遗产结构的现实模型。然后，将通过基于传统Winkler方法的等效离散模型设计ViBa。此外，还将与工业合作伙伴一起探索ViBa安装的优化，以使该技术具有成本效益。研究问题1）最佳ViBa设计参数是什么以及如何确定？2)ViBa设计参数对模型不确定性的敏感度是多少？3)ViBa会是一个具有成本效益的解决方案吗？

Historic structures in seismic prone areas are extremely vulnerable. The main reason is that such structures have not been properly designed to withstand earthquakes and also because the construction materials deteriorate with the time. The most recent earthquakes, such as the one in Norcia 2016 are clear examples manifesting the necessity to act promptly to protect heritage structures from such natural disaster. Seismic protection of heritage structures is an unresolved research problem that not only is a public safety issue but also adds to the constraints for preserve the artistic value of heritage buildings. In this regard, there is a clear gap in the knowledge that leads to the research question on how it is possible to protect a structure without modifying it. Previous research suggests that protecting structures by seismic action is managed using localised solutions such as isolators and dampers. Research also shows that one main reason is that the introduction of control devices in existing structures is too invasive, costly and requires the demolishing of some structural and/or non-structural component. For heritage structures clearly such technologies cannot be applied and therefore no seismic protection actions are currently taken to protect such artistic treasures. Research has yet to examine the potential of non-invasive devices for protecting heritage structures. The proposed research will investigate for the first time the use of the novel vibrating barriers (ViBa) to reduce seismic vibrations of heritage structures. Vibrating barriers (ViBa) are massive structures hosted in the soil and tuned to reduce the vibrations of neighbourhood structures through a structure-soil-structure interaction mechanism. As the ViBa is detached from the structure it is particularly suitable for heritage structures so to entirely preserve their original structure without any alteration. The proposed research will aim to establish a general methodology to protect heritage structures through a project that tests the role of ViBa and unknown design parameters. Technical details will be developed through a case study recommended by the cultural partners. In particular the design of the ViBa will require first the numerical modelling of the heritage structure and the soil underneath through a finite element approach. In this regard the cultural partners will provide the data to establish a realistic model of the heritage structure. The ViBa will be then designed through an equivalent discrete model based on the traditional Winkler approach. Moreover, the optimization of the installation of ViBa will be explored with the industrial partner to make this technology cost-efficient.Research questions1) What are optimal ViBa design parameters and how are determined?2) What is the sensitivity of the ViBa design parameters to the model uncertainties?3) Will the ViBa be a cost-effective solution?