FOR 1136: Simulation of Geotechnical Construction Processes with Holistic Consideration of Constitutive Lows in Soils

FOR 1136：全面考虑土壤本构低点的岩土施工过程模拟

• 批准号: 76838227
• 金额: --
• 依托单位: Lehrstuhl für Bodenmechanik, Grundbau u Umweltgeotechnik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/76838227?language=en
• 关键词: 1136; Simulation; Geotechnical; Construction; Processes

Construction in urban environment requires frequently excavation pits. The shoring of these pits have to be constructed in such a manner that its serviceability and the respective of the nearby structures are assured. Within the Research Unit it is expected to consider the overall changes of the soil conditions throughout the entire process of one or of diverse geotechnical construction processes using non-linear, robust, realistic and modern constitutive laws for soils and powerful, stable numerical modelling strategies for the geotechnical problems associated with. Due to the fact that geotechnical methods and construction processes are diverse and manifold, the intention of the Research Unit is not to consider all possible variations of those construction processes. Furthermore, the Research Unit will concentrate the efforts on selected geotechnical problems. For the description of the selected processes it is, on one hand, necessary to implement static, cyclic and dynamic simulation strategies and, on the other hand, the soil has to be regarded as a mixture of grain skeleton with water and air contents. Besides of these fundamental considerations are also further effects related to the contact between soil and structure, which have to be taken into account. Some of the fundamental questions to be answered are: (1) Is there any significant influence of the construction process on the design of the elements to be installed or on the serviceability of already nearby existing structures? If so, under which conditions are these influences significant and in which simplified manner can these be implemented in the design process? (2) May existing constitutive laws be improved for a realistic description of repeated loading and unloading? (3) Can the dynamic installation of piles (installation by vibration or dynamic impact) and the holistic consideration of the stress-strain paths throughout the entire construction process in soil be analysed with a dynamic coupling of the solid and fluid material phases according to the p-u or u-p-U-formulation in order to obtain realistic results? How can the numerical stability of the chosen algorithms and methods be obtained? The answer of the above and further questions are the scope of work of the Research Unit.

在城市环境中进行施工，需要经常开挖基坑。这些基坑的支护必须以确保其可用性和附近结构的相应性的方式进行施工。在研究单位内，预计将考虑在一个或不同的岩土工程施工过程的整个过程中土壤条件的整体变化，使用非线性，稳健，现实和现代的土壤本构关系和强大的，稳定的数值建模策略相关的岩土工程问题。由于岩土工程方法和施工过程多种多样，研究组的目的不是考虑这些施工过程的所有可能变化。此外，研究组会集中研究选定的岩土工程问题。对于所选过程的描述，一方面，有必要实施静态，循环和动态模拟策略，另一方面，土壤必须被视为具有水和空气含量的颗粒骨架的混合物。除了这些基本考虑因素之外，还必须考虑与土壤和结构之间的接触有关的进一步影响。需要回答的一些基本问题是：（1）施工过程对待安装元件的设计或对附近现有结构的适用性是否有任何重大影响？如果是，在哪些条件下这些影响是显著的，在设计过程中可以以何种简化方式实现这些影响？(2)现有的本构关系是否可以改进，以更真实地描述重复加载和卸载？(3)为了获得真实的结果，是否可以根据p-u或u-p-U公式，通过固体和流体材料相的动态耦合来分析桩的动态安装（通过振动或动态冲击进行安装）以及对土壤中整个施工过程中的应力-应变路径的整体考虑？如何获得所选算法和方法的数值稳定性？对上述问题和其他问题的答复属于研究股的工作范围。