LASSIE: Low life cycle cost Sand-wich Isolation System for Seismic Risk Reduction

LASSIE：生命周期成本低的夹层隔震系统，可降低地震风险

• 批准号: EP/X010074/1
• 负责人: Nicholas Alexander
• 金额: $ 94.91万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX010074%2F1
• 关键词: LASSIE; Low; life; cycle; cost

LASSIE is an innovative, inexpensive technology for improving the safety and resilience of structures in earthquake regions. Through cutting edge research, world-class UK-based experimental facilities, international collaboration, and synergies with UK industry it builds upon existing research developments to qualify a new design method of seismic isolation in both developed and developing countries. The aim is to create a novel, low-cost sliding isolation system that will be a quantum leap forwards in the design of new seismically protected low-rise buildings. This technology will ensure life-safety for beyond design level earthquakes and significantly reduce life-cycle costs by maintaining full post-earthquake operability. In many cases, an earthquake causes the ground underneath a building to move, predominately, side-to-side (horizontally) and so it drives the building to oscillate from side-to-side (horizontally). These potentially large building oscillations must be mitigated in some way and typically this is achieved by permitting the building to absorb this aberrant kinetic energy by permitting damage (in the form of ductile deformations) to occur within the building. While this capacity design approach is widely adopted, it does impose a large financial repair/rebuild cost on society after a design level earthquake. This cost is compounded by economic downturns generated by the 'loss of use' of many large and important infrastructure artefacts. An alternative approach is seismic isolation systems which seek to partially uncouple the ground from the building at the foundation level. By permitting sliding to occur at the foundation level between the ground and the building, the building is 'released' from the ground and hence is subjected to a much-reduced level of seismic excitation. Consequentially, this either greatly reduces structural damage or enables the superstructure to remain undamaged during the design earthquake. However, the seismic isolation systems require expensive foundation/basement to accommodate them and, although overall costs are currently reducing, their widespread adoption is still not viewed as universally financially justifiable. Nevertheless, the concept that a building can be uncoupled from the damaging effects of the ground movement produced by a strong earthquake would be very appealing if costs can be reduced for ordinary residential buildings, whose large contribution to the building stock effectively drives the cost of seismic safety. Thus, the aim of this proposal is to develop a low life-cycle cost 'sand-wich' seismic isolation system that will ensure full-life safety and full post-event building operability. This proposed system is composed of a thick reinforced concrete (RC) foundation slab sitting above a 'sand-wich' layer (PVC/sand/PVC) which permits sliding to occur during large ground excitations. The novel re-centring of this sliding system is achieved by a combination of normally loaded, sliding cables (that run through ungrouted ducts within the RC ground slab) and a group of micropile/anchors and ring beam. This system makes use of state-of-the-art non-smooth nonlinear dynamics theory (slip-stick behaviour), the nonlinear elastic behaviour of geometrically loaded cables and dynamic/shock loaded soil-structure interaction of micropile groups. In this proposal every element/component of the novel design shall be tested experimentally in the newly commissioned 'UKCRIC - Bristol Soil-Foundation-Structure Interaction Facility (SoFSI)' EP/R012806/1 and computationally to ensure the performance of the proposed design is validated within a Technology Readiness Level (TRL) Framework methodology.

LASSIE是一种创新的，廉价的技术，用于提高地震地区结构的安全性和弹性。通过尖端的研究，世界一流的英国实验设施，国际合作以及与英国工业的协同作用，它建立在现有的研究发展基础上，在发达国家和发展中国家都有资格获得新的隔震设计方法。其目的是创造一种新颖的，低成本的滑动隔震系统，这将是一个量子飞跃，在新的抗震保护低层建筑的设计。这项技术将确保生命安全，超过设计水平的地震和显着降低生命周期成本，通过保持充分的震后可操作性。在许多情况下，地震会导致建筑物下方的地面移动，主要是左右（水平）移动，因此它会驱动建筑物左右（水平）振荡。必须以某种方式减轻这些潜在的大的建筑物振动，并且通常这通过允许建筑物内发生损坏（以延性变形的形式）来允许建筑物吸收这种异常动能来实现。虽然这种能力设计方法被广泛采用，但在设计水平地震后，它确实会给社会带来巨大的财政修复/重建成本。许多大型和重要的基础设施人工制品“失去使用”造成的经济衰退加剧了这一成本。另一种方法是地震隔离系统，它试图在地基水平将地面与建筑物部分分离。通过允许滑动发生在地面和建筑物之间的地基水平，建筑物从地面“释放”，因此受到的地震激励水平大大降低。因此，这要么大大减少了结构损坏，要么使上部结构在设计地震期间保持完好。然而，地震隔离系统需要昂贵的地基/地下室来容纳它们，尽管目前总体成本正在降低，但它们的广泛采用仍然不被视为普遍的财政合理。尽管如此，如果普通住宅建筑的成本能够降低，那么建筑物可以与强烈地震产生的地面运动的破坏性影响脱钩的概念将非常有吸引力，因为普通住宅建筑对建筑物的巨大贡献有效地推动了地震安全成本。因此，本提案的目的是开发一种低生命周期成本的“三明治”隔震系统，以确保整个生命周期的安全性和完整的事后建筑可操作性。该建议的系统是由一个厚厚的钢筋混凝土（RC）的基础板坐在上面的“三明治”层（PVC/砂/PVC），允许滑动发生在大地面激励。该滑动系统的新型重新定心是通过正常加载的滑动电缆（穿过钢筋混凝土地面板内的未灌浆管道）和一组微型桩/锚和环梁的组合来实现的。该系统利用了最先进的非光滑非线性动力学理论（滑粘行为），几何加载电缆的非线性弹性行为和动力/冲击加载的微型群桩土-结构相互作用。在本建议书中，新设计的每个元件/组件应在新委托的“UKCRIC -布里斯托土壤-地基-结构相互作用设施（SoFSI）”EP/R 012806/1中进行实验测试，并进行计算，以确保在技术准备水平（TRL）框架方法内验证建议设计的性能。

项目成果

Experimental determination of friction at the interface of a sand-based, seismically isolated foundation

砂基隔震地基界面摩擦力的实验测定

• DOI: 10.1007/s00707-023-03802-0
• 发表时间: 2023
• 期刊: Acta Mechanica
• 影响因子: 2.7
• 作者: Sezer Y