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.

预制混凝土保温板常用作外墙。它们是有利的，因为它们是结构和热效率。它们由两层钢筋混凝土层围绕着一层绝缘层组成。混凝土层是用一种叫做剪切接头的纽带连接起来的。在今天使用的大多数面板中，剪切连接件在荷载作用下变形，导致混凝土层之间的相对滑移。相对于实心面板，这种滑移降低了面板的强度和刚度（即它们在相同载荷下变形更多）。在当前的设计指南中没有考虑滑移；面板的设计是基于保守的假设和设计师的经验。