Modelling of Deformation and Instability in Geomechanics

提案的基本主题是可持续性和管理与潜在危害相关的风险。需要关注的不仅是我们的城市，还有连接城市中心的基础设施。该提案将涉及两方面的研究：一是加强我们对路面结构中使用的颗粒材料的力学行为的理解，目的是改进考虑到不断变化的环境条件的设计；二是发展分析技术，以更好地处理不稳定性的建模和预测，特别是更好地模拟泥石流和山体滑坡，以及沿沿海地区或河流岸线发生的水流滑坡中的土壤-水相互作用。泥石流有可能破坏自然水生栖息地，破坏海上管道和基础设施，并对防洪产生负面影响。瓦砾和山体滑坡对我们的交通网络和基础设施构成直接威胁。

The underlying theme of the proposal is sustainability and managing risk associated with potential hazards. It is not only our cities that require attention but also the infrastructure joining the urban centers. The proposal will address two lines of research: one dealing with enhancing our understanding of the mechanical behaviour of granular materials used in pavement structures with the purpose of improving design that takes into account changing environmental conditions; and the second is to develop the analytical technology to better deal with the modelling and prediction of instabilities, in particular to better model debris slides and landslides, as well as the soil-water interaction in flow slides that occur along coastal areas or river shorelines. Flow slides have the potential to destroy natural aquatic habitats, damage offshore pipelines and infrastructure and negatively impact flood defenses. Debris and landslides are a direct threat to our transportation network and infrastructure. The objectives of the proposed research, which compliments what has been done in the past, are to: (a) model reclaimed asphalt concrete (RAP) - natural aggregate mixtures to examine the interaction between RAP particles and natural aggregate taking into account cyclical loading and temperature. The specific modelling of aggregate interaction will be carried out via discrete element modelling based on stress-assumed polygonal finite elements and nonlinear joint elements. This framework will allow naturally taking into account anisotropy and its effect on macro-behaviour. The frameworks of hyperplasticity and high cycles accumulation modelling will be used to study and more accurately assess development of permanent pavement deflections (strains) due to granular base layers that lead to rutting and fatigue failure. The experimental research undertaken by applicant over the past has led to a large data bank (insitu and lab) that will be used for model development and calibration. (b) develop two-dimensional finite element (FEM) and material point method (MPM) model that explicitly takes into soil-water interaction, as well as temperature influences. The modeling framework will build on the technology that has been developed to date to tackle multi-scale/multi-mechanism phenomena taking into account a nonlinear far-from-equilibrium thermodynamic approach.