Multidimensional constitutive and numerical modeling in geotechnical seismic analysis and design

岩土地震分析和设计中的多维本构和数值建模

• 批准号: RGPIN-2015-03777
• 负责人: Taiebat, Mahdi
• 金额: $ 2.48万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=636228
• 关键词: Multidimensional; constitutive; numerical; modeling; geotechnical

The future of modeling in geotechnical earthquake engineering will be based almost exclusively on Performance-Based Seismic Design philosophy. PBSD requires a paradigm shift toward a displacement or deformation-based design as opposed to the traditional force-based design. It is more rational than the conventional analysis and design methods, and leads to more cost effective construction or safer design. PBSD demands an adequate measure of reliability of computed deformations. A realistic simulation of deformation of geo-structures subjected to irregular earthquake loading is very complex. The simulation tools should handle 3D dynamic analysis based on effective stress formulation, fully coupled solid-pore fluid interaction, and parallel/cloud computing features for handling large problems. The most important issue is proper constitutive modeling of the soil matrix. Current soil models used in engineering practice do not include many of the very important factors that affect the stress-strain relationship. It is also extremely challenging to address multidirectional cyclic loading of earthquakes. From discussion made with major practitioners, such as BC Hydro who deal with earth dams, it becomes clear that their main concern is with the different responses given by the different models that are available; in some cases these differences are significant enough to cause great concern.

岩土地震工程建模的未来将几乎完全基于基于性能的抗震设计理念。PBSD需要向基于位移或变形的设计转变，而不是传统的基于力的设计。它比传统的分析和设计方法更合理，并导致更节省成本的建设或更安全的设计。PBSD要求计算变形的可靠性有足够的度量。不规则地震荷载作用下岩土结构变形的真实模拟是非常复杂的。模拟工具应基于有效应力公式、完全耦合的固体-孔隙流体相互作用以及用于处理大型问题的并行/云计算功能来处理3D动态分析。最重要的问题是适当的本构模型的土壤基质。目前在工程实践中使用的土壤模型不包括许多非常重要的因素，影响应力-应变关系。解决地震的多方向循环荷载也是极具挑战性的。从与主要从业者（如处理土坝的BC Hydro）的讨论中可以看出，他们主要关注的是可用的不同模型给出的不同响应;在某些情况下，这些差异足以引起极大的关注。