Integrity of Shear Connection Mechanisms in Precast Concrete Insulated Wall Panels

预制混凝土保温墙板剪力连接机构的完整性

• 批准号: RGPIN-2017-05069
• 负责人: Tomlinson, Douglas
• 金额: $ 1.6万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=710703
• 关键词: Integrity; Shear; Connection; Mechanisms; Precast

Precast concrete insulated panels are commonly used as exterior walls. They are advantageous as they are structurally and thermally efficient. They consist of two reinforced concrete layers that surround a layer of insulation. The concrete layers are connected with ties called shear connectors. In most panels used today, shear connectors deform under load resulting in relative slip between the concrete layers. This slip reduces panel strength and stiffness (i.e. they deform more under the same load) relative to solid panels. Slip is not accounted for in current design guides; panels are designed based on conservative assumptions and designer experience. Slip is expected to increase as panels degrade over the long term from cycling structural and environmental loads. Panels also deform from thermal bowing on hot and cold days. Thermal bowing creates gaps between walls and reduces insulation quality. There are no existing design techniques that predict long term degradation and thermal bowing in these panels. Research is required to overcome this knowledge gap and ensure that engineers and practitioners are able to efficiently design and accurately predict the response of these panels over the short and long term. The long term objective of the proposed program is to better understand and improve the performance of precast concrete insulated concrete panels subject to structural and environmental loads and contribute toward the design of optimized and durable structural members. Guides will be developed that will allow engineers and manufacturers to accurately design and analyze panels subject to structural and environmental loads for the first time. To accomplish this, the program will focus on three short term objectives: (1) develop further understanding of the short term behaviour of precast concrete insulated wall panels by conducting structural tests on panel design parameters that have not been addressed before; (2) explore fundamental mechanisms (cyclic structural loading, thermal bowing, and environmental damage) that affect these panels over the long term; and (3) develop models validated by experimental results that predict the structural response of these panels over the short and long term. This research program will train 6 graduate and 5 undergraduate Highly Qualified Personnel to apply their research findings and professional skills development to become experts in the field of precast concrete insulated wall panels and reinforced concrete structures. Completing the research objectives and transferring this knowledge to engineers and the construction industry will allow structurally and thermally optimized panels to be developed. These more efficient walls will reduce: greenhouse gas emissions during fabrication and transportation, heating and cooling costs for building occupants, and the costs of maintaining building exteriors.

预制混凝土绝缘面板通常用作外壁。它们在结构和热效率上是有利的。它们由围绕绝缘层的两个钢筋混凝土层组成。混凝土层与称为剪切连接器的领带连接。在当今使用的大多数面板中，剪切连接器在负载下变形，导致混凝土层之间的相对滑动。相对于实心板，该滑动可降低面板的强度和刚度（即它们在相同的载荷下变形更多）。在当前的设计指南中不考虑滑移；面板是根据保守的假设和设计师经验而设计的。 随着面板在长期内从骑自行车结构和环境负载中的长期降解，预计滑移将增加。面板在炎热和寒冷的日子上也因热鞠躬而变形。热鞠躬会在墙壁之间造成缝隙，并降低了隔热质量。没有现有的设计技术可以预测这些面板中的长期退化和热鞠躬。需要研究以克服这一知识差距，并确保工程师和从业人员能够有效地设计并准确预测这些小组在短期和长期内的响应。 拟议程序的长期目标是更好地理解和改善由结构和环境负载的预制混凝土隔热混凝土面板的性能，并有助于设计优化和耐用的结构成员。将开发指南，这将使工程师和制造商能够首次准确设计和分析面板。为此，该计划将集中在三个短期目标上：（1）通过对之前尚未解决的面板设计参数进行结构测试，进一步了解预制混凝土绝缘墙板的短期行为； （2）探索长期影响这些面板的基本机制（环状结构载荷，热弓和环境损害）； （3）开发通过实验结果验证的模型，这些模型可以预测这些面板在短期和长期内的结构响应。 该研究计划将培训6名毕业生和5名本科高素质的人员，以应用其研究结果和专业技能发展，以成为预制混凝土隔热墙板和钢筋混凝土结构领域的专家。完成研究目标并将这些知识转移给工程师，建筑行业将允许开发结构和热优化的面板。这些更有效的墙壁将减少：制造和运输过程中的温室气体排放，建筑物乘员的供暖和冷却成本以及维护建筑物外部的成本。