Load Sharing mechanism of Piled-Raft-Foundations

桩筏基础的荷载分配机制

• 批准号: RGPIN-2014-06627
• 负责人: Hanna, Adel
• 金额: $ 1.6万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=612337
• 关键词: Load; Sharing; mechanism; Piled; Raft

In practice, deep foundations are made of a set of piles connected together with a concrete raft. The role of the raft is to transfer the column load to the piles uniformly. It does not however share the building load with the piles. While engineers often design raft foundation alone to carry the entire building load. Accordingly the design of pile foundations is regarded as highly conservative, in fact uneconomical. The concept of Piled-Raft-Foundation has been increasingly receiving recognition around the world. While engineers recognize the contribution of the raft to the foundation loads, research in this field has been lagging to estimate the raft share. This is due to the fact that interaction among the piles/soil/raft is complex in nature and field testing is difficult at best. In the literature, several reports can be found dealing with the load-settlement relationship of piled-raft foundations. Nevertheless, these reports are based on limited modeling, and failed to recognize the effect of some vital governing parameters and the three-dimensional stressdeformation mechanism, which take place within the piled-raft foundation. In this proposal; experimental and numerical investigations on piles-raft foundation will be performed. A three-dimensional numerical model will be developed to simulate the case of piled-raft foundation and laboratory tests will be conducted on prototype experimental set-up. After validating the numerical model with the experimental results and the data available in the literature, the model will be used examine the parameters, believed to govern the performance of this foundation. The results of this study will have significant economic impact on the construction of piled-raft foundations for high-rise buildings without compromising on the safety. It is expecting that the design theories, guidelines and recommendations developed will be incorporated in the Canadian Foundation Engineering manual and American Society of Civil Engineers manual of practice. It is equally important to take note that this project will provide training to the Highly Qualified Personnel and scientists.

在实践中，深基础是由一组用混凝土筏子连接在一起的桩组成的。 筏板的作用是将柱荷载均匀地传递到桩上。然而，事实并非如此 与桩一起分担建筑荷载。虽然工程师经常将筏板基础单独设计为可承载 整个建筑的负荷。因此，桩基础的设计受到高度重视。 保守，实际上并不经济。 桩筏基础的概念在世界各地得到了越来越多的认可 世界。虽然工程师们认识到筏子对基础荷载的贡献，但在 这一领域在估计浮筏份额方面一直滞后。这是由于以下事实： 桩/土/筏的性质复杂，现场测试充其量也是困难的。 在文献中，可以找到几个关于荷载-沉降关系的报告。 桩筏基础。然而，这些报告是基于有限的建模，未能 认识一些关键控制参数的影响和三维应力变形 机制，这发生在桩筏基础内。 在本方案中，将对桩筏基础进行试验和数值研究。 已执行。建立了三维数值模型来模拟桩筏的情况。 将在样机实验装置上进行基础和实验室测试。之后 用实验结果和已有的数据验证了数值模型。 文献中，该模型将被用来检验参数，被认为是支配性能的 这个基金会。 研究结果将对桩筏的建设产生重大的经济影响。 在不影响安全性的情况下，为高层建筑提供基础。它期待着 制定的设计理论、指导方针和建议将被纳入加拿大 《基础工程手册》和《美国土木工程师学会实用手册》。 同样重要的是要注意到，该项目将为高素质的人员和科学家提供培训。