Utilization of Ultra High Performance Concrete for Offshore Applications.

超高性能混凝土在海上应用中的利用。

• 批准号: RGPIN-2015-04159
• 负责人: Marzouk, Hesham
• 金额: $ 1.46万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=677342
• 关键词: Utilization; Ultra; Performance; Concrete; Offshore

The development of Ultra High Performance Fiber Concrete (UHP-FRC) is deemed as one of the most promising technological advances in material applications suitable for structural Engineering. The new material exhibits exceptional mechanical and durability properties. Concepts of particle packing using nanotechnology have been taken one step further to produce it. The enhanced ductility, impact resistance and energy absorption capacity of the new concrete makes it an ideal material for use in high resistance structures. The present research investigation will be focused on studying the concrete plate under static and impact loading. The use of thin plate can be used as a concrete form for thick mega important structures like offshore and nuclear containment structures or it can be attached to building exterior panels to produce safer more sustainable structural shield in the future.***The new material has been used for different parts on the roof, base slab and other parts of the new offshore Hebron gravity concrete platforms. UHP-FRC has an excellent resistance to spalling, scabbing, and fragmentation, making it an ideal material for wave forces and sea ice for the splash zone. The new material is very well used for offshore wind turbine structures applications.***The cracking, tension stiffening and reinforcement ratios of UHP-FRC plate are important design factors for any offshore structure. The impact loading of UHP-FRC plate under dropped weight will be investigated experimentally, analytically and numerically. Four analytical models will be developed based on the critical impact energy for radial cracking, spalling, tunneling (scabbing) and penetration. The Random Decrement (RD) method will be used determine the dynamic properties of the tested plates before and after testing. The natural frequency, damping ratio, normalized RD and normalized deflection will be determined for the tested plates at different nodes. A critical impact energy expressions will be developed after considering the change of the modulus of elasticity due to Dynamic Impact Factor (DIF) for quasi-static domain, and dynamic domain. ***A numerical investigation is being developed using a concrete damage plasticity constitutive mode suitable for large deformation. A series of laboratory tests has been conducted at Ryerson lab under supervision of the applicant to determine the identification model parameters. The damage plasticity model under strain rate dependent is considered as a modification of the Drucker-Prager strength hypothesis. Tensile and  damage parameters will be used for the model. The developed numerical FE model will be used on the simulation of the impact problem using explicit dynamic analysis technique. The long term objective will be focused on the successful development of an efficient design of a thin plate to be used as a shield against impact for important structures. ***********

超高性能纤维混凝土(UHP-FRC)的发展被认为是结构工程材料应用中最有前途的技术进步之一。这种新材料具有出众的机械性能和耐用性。使用纳米技术的颗粒堆积的概念已经更进一步地产生了它。新型混凝土的延展性、抗冲击性和能量吸收能力增强，使其成为用于高阻力结构的理想材料。本文将集中研究混凝土板在静力和冲击荷载作用下的受力性能。薄板的使用可以作为厚重的巨型结构的混凝土模板，如海上和核安全壳结构，也可以附加在建筑外板上，以生产更安全、更可持续的结构盾牌。*这种新材料已经被广泛用于新的海上希伯伦重力混凝土平台的屋顶、底板和其他部分的不同部分。UHP-FRC具有优异的抗剥落、结痂和碎裂性能，使其成为波浪作用力和飞溅区海冰的理想材料。这种新材料非常适用于海上风力机结构应用。*超高强度纤维混凝土板的开裂、抗拉加强和配筋率是任何海上结构的重要设计因素。本文将从试验、分析和数值三个方面研究落锤作用下超高强度纤维混凝土板的冲击载荷。将根据径向破裂、剥落、隧道开挖(结垢)和侵彻的临界冲击能建立四个分析模型。试验前后将采用随机递减(RD)法确定受试板的动态特性。确定了受试板在不同节点处的固有频率、阻尼比、归一化Rd和归一化挠度。在考虑准静态域和动态域由于动态冲击因子(DIF)引起的弹性模量变化后，将推导出临界冲击能表达式。在申请人的监督下，瑞尔森实验室进行了一系列实验室测试，以确定识别模型参数。应变率相关的损伤塑性模型被认为是对Drucker-Prager强度假设的修正。该模型将使用拉伸和弹性损伤参数。开发的数值有限元模型将用于使用显式动力学分析技术模拟碰撞问题。长期目标将集中在成功开发一种高效的薄板设计，用作重要结构的冲击防护。***********