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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=653011
• 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，深基础是由一组与混凝土筏连接在一起的桩组成的。*筏的作用是将柱荷载均匀地传递到桩上。然而，它并不*与桩分担建筑荷载。而工程师经常单独设计筏板基础来承载整个建筑荷载。因此，桩基础的设计被认为是高度*保守的，实际上是不经济的。*桩筏基础的概念已经越来越受到世界各地的认可。虽然工程师认识到筏板对基础荷载的贡献，但该领域的研究在估计筏板份额方面一直滞后。这是因为桩/土/筏之间的相互作用本质上是复杂的，现场测试是很困难的。*在文献中，可以找到一些关于桩-筏的荷载-沉降关系的报告。基础。然而，这些报告基于有限的模型，未能*认识到发生在桩筏基础内的一些重要控制参数和三维应力变形*机制的影响。*在本提案中；将*对桩筏基础进行实验和数值研究。将开发三维数值模型来模拟桩筏*基础的情况，并对原型实验装置进行实验室测试。在*用实验结果和文献中可用的数据验证数值模型后，该模型将用于检查参数，这些参数被认为控制着*该基础的性能。*这项研究的结果将对在不影响安全的情况下建造高层建筑的桩筏*基础。预计所制定的*设计理论、指南和建议将被纳入加拿大*基础工程手册和美国土木工程师协会实践手册中。 *同样重要的是要注意该项目将为高素质人员和科学家提供培训。