CT- and multi-monitoring ready thermo-frozen-hydro-mechanical 3D loading system

CT 和多监测就绪热冷冻水机械 3D 加载系统

• 批准号: 500412763
• 金额: --
• 依托单位: Christian-Albrechts-Universität zu Kiel
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2022
• 资助国家: 德国
• 起止时间: 2021-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/500412763?language=en
• 关键词: CT; multi; monitoring; ready; thermo

In view of the upcoming climate change, the analysis of frozen soil materials is of fundamental importance for the adaptation or mitigation in urban areas as well as for the understanding of occurring geological phenomena. The currently existing permafrost soils are essential in securing the organic carbons encapsulated therein and in stabilizing the existing soil structures, such as constantly and seasonally frozen soils (cryosols) in the cryosphere, embankments, foundations, due to the high rigidity of the subsoil. Here, the basic understanding of changing the coupled cryo-hydro-mechanical soil properties must be improved, so that in addition to the changed chemical, biological processes through the thawing or the transition of the cyclical, alternating thawing / freezing of upper cryosols, the resulting hydraulic, mechanical Changes such as weathering, loss of stiffness and strength, frost-related mixing and erosion can be assessed and modeled. Changes in the cryopedogenic processes such as ice segregation, ice accumulation and cryometamorphosis under alternating thawing / freezing are also unknown.In the adaptation of urban life and the mitigation of increasing urban heat hotspots, the cooling of infrastructures becomes more important. To do this, urban ice stores must be built on a geological scale. Initial research on this is already in progress. From a structural engineering point of view, freezing processes with the load-bearing capacity or protection against failure are known. Cyclical freezing processes, such as those required for the use of ice storages, are completely unknown in terms of their effects. The effects of cyclical freeze-thaw hysteresis on the volumetric pore space and structure changes, in the Atterberg limits or mechanical strength and compressibility degradations have hardly been analyzed and have significant effects on sediments with a larger proportion of fine particles. Secure geomechanical forecasts for these sediments for cyclical freeze-thaw cycles are not yet possible.For the modeling of the cyclic cryo-hydro-mechanical material behavior of frozen soils, a large number of different experimental tests are to be carried out, for which a previously non-existent laboratory device is to be purchased. For the experimental 3D analyzes of the soil samples, a 3-dimensional pressure system for cyclical cryo-thermo-hydro-mechanical loading is to be acquired, which in addition to the cyclical freezing / thawing, the additional installation of further monitoring devices (digital cameras for particle image Velocity, thermography cameras, laser technology, μCT's, radar, etc.) are allowed directly on the sample and during the test process, so that local changes in the structure can be recorded in high resolution as tomography or surface plot and transferred to the modeling.

鉴于即将发生的气候变化，对冷冻土壤材料的分析对于城市地区的适应或缓解以及对发生地质现象的理解至关重要。当前现有的永久冻土土壤对于保护其封装的有机碳和稳定现有的土壤结构（例如，由于地下土壤的较高刚性，都必须不断和季节性冷冻的土壤（冷冻溶剂）。在这里，必须改善对改变耦合的冷冻水种机械土壤特性的基本理解，以便除了通过融化或过渡到周期性的，替代性融化 /冷冻溶液的过渡外，除了过渡或过渡时，上层冷冻溶液的冻结 /冷冻，以及由此产生的液压变化，例如，液态和僵化的型号和模型，造成了僵化和模型的损失，并混合了混合，并混合了混合，并混合了混合。在替代解冻 /冻结下，冰分离，冰的积累和哭泣的冰淇淋等冷冻生成过程的变化也是未知的。在适应城市生活和减轻城市热热点的缓解时，基础设施的冷却变得更加重要。为此，城市冰店必须以地质规模建造。对此的初步研究已经在进行中。从结构工程的角度来看，已知具有承重能力或防御故障的冻结过程。在其影响方面，周期性的冷冻过程（例如使用冰储存所需的过程）是完全未知的。周期性冻结滞后滞后对体积孔隙空间和结构变化的影响，在Atterberg限制或机械强度和机械强度以及可及性降解的影响几乎没有分析，并且对具有较大优质颗粒比例较大的沉积物具有显着影响。这些沉积物的安全地质力学预测尚不可能进行周期性冷冻循环。对于循环冷冻 - 氢化机械材料的建模，将要进行大量不同的实验测试，为此，将购买先前不存在的实验室设备。 For the experimental 3D analysis of the soil samples, a 3-dimensional pressure system for cyclical cryo-thermo-hydro-mechanical loading is to be acquired, which in addition to the cyclical freezing / thawing, the additional installation of further monitoring devices (digital cameras for particle image Velocity, thermographic cameras, laser technology, μCT's, radar, etc.) are allowed directly on the sample and during the test process,因此，可以将结构的局部变化记录为高分辨率或表面图，并转移到建模中。