Fire Performance of Timber-Concrete Composite (TCC) Systems in Mass Timber Buildings

大体积木结构建筑中木-混凝土复合材料 (TCC) 系统的防火性能

• 批准号: RGPIN-2021-04076
• 负责人: Salem, Osama
• 金额: $ 1.89万
• 依托单位: Lakehead University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=749417
• 关键词: Fire; Performance; Timber; Concrete; Composite

In a new era full of possibilities for manufacturing large timber sections made of engineered wood, i.e., glued-laminated timber (glulam), cross-laminated timber (CLT) and nailed-laminated timber (NLT) sections, strength and structural integrity of such sections can be retained for much longer time in fire. As a result, several tall buildings made primarily of timber are increasingly being constructed worldwide. Floor systems in such buildings can even be made stronger and span longer distances to allow designers greater versatility in terms of floor plan and promote for open concept design in modern buildings by adding a top layer made of concrete that allows the formation of Timber-Concrete Composite (TCC) floor systems with the use of sufficient shear connections. In this composite system, the advantageous mechanical properties of both materials are efficiently utilized and thus, several advantages can be achieved for a more robust floor system, if compared to timber floors such as those made solely of CLT or NLT panels. Among the several advantages of utilizing TCC floor systems are greater strength, durability, and much improved acoustics and vibration performance characteristics. Unfortunately, experimental work on TCC systems in fire conditions is not as extensive as at ambient temperature, and thus one very important area that warrants further investigation is the behaviour of TCC floor systems in fire conditions with focus on certain aspects. For instance, most previous experimental studies on TCC floor systems were of small size, small number and/or representing one-way floor assemblies; whereas in the proposed research program, twenty-four (24) large-scale two-way TCC slab-type floor assemblies utilizing CLT and NLT panels will be examined in fire conditions. Also, it is very rare to find research studies that address the effect of inter-panels joint connections on the structural fire behaviour of TCC floor systems, and thus those test assemblies with CLT panels will include spline panel-to-panel connections. In addition, the use of a supporting framing system made of glulam beams along the perimeter of the TCC floor slab to enhance the membrane action of the concrete slabs in fire is something that has never been presented in the available literature so far. Therefore, it is believed that the proposed research program will lead to: development of new and reliable experimental data and possible implementation of design models for TCC slab-type floor systems in fire conditions in the future version of CSA O86 standard (scientific impact); development of FE models that can simulate the actual behaviour of those TCC floor assemblies with the selected shear connections in fire conditions (technological impact); indirectly support the Canadian wood industry through the development of new design models (economic impact); and allow more robust, sustainable material-made, and fire safe mass timber buildings for Canadians (social impact).

在一个充满可能性的新时代，制造由工程木材制成的大型木材型材，即胶合层压木材（胶合木）、交叉层压木材（CLT）和钉合层压木材（NLT）型材，这些型材的强度和结构完整性可以在火灾中保持更长时间。因此，世界各地越来越多地建造一些主要由木材制成的高层建筑。此类建筑物中的楼板系统甚至可以变得更坚固，跨度更长，从而使设计人员能够在平面图方面具有更大的多功能性，并通过添加混凝土制成的顶层来促进现代建筑中的开放式概念设计，从而允许使用足够的剪力连接形成木材-混凝土复合材料（TCC）楼板系统。在这种复合材料系统中，两种材料的有利机械性能得到了有效利用，因此，与仅由 CLT 或 NLT 面板制成的木地板相比，可以实现更坚固的地板系统的多个优点。使用 TCC 地板系统的诸多优点包括更高的强度、耐用性以及显着改善的声学和振动性能特征。 不幸的是，TCC 系统在火灾条件下的实验工作并不像在环境温度下那样广泛，因此值得进一步研究的一个非常重要的领域是 TCC 地板系统在火灾条件下的行为，重点关注某些方面。例如，之前大多数关于 TCC 地板系统的实验研究都是小尺寸、少量和/或代表单向地板组件；而在拟议的研究计划中，二十四 (24) 个使用 CLT 和 NLT 面板的大型双向 TCC 板式地板组件将在火灾条件下进行检查。此外，很少有研究能够解决板间接头连接对 TCC 地板系统结构防火性能的影响，因此那些采用 CLT 板的测试组件将包括花键板与板之间的连接。此外，沿 TCC 楼板周边使用由胶合木梁制成的支撑框架系统来增强混凝土板在火灾中的膜作用，这是迄今为止现有文献中从未提出过的。因此，我们相信所提出的研究计划将导致： 开发新的、可靠的实验数据，并可能在未来版本的 CSA O86 标准（科学影响）中实施 TCC 板式楼板系统在火灾条件下的设计模型；开发有限元模型，该模型可以模拟在火灾条件下具有选定剪力连接的 TCC 地板组件的实际行为（技术影响）；通过开发新的设计模式间接支持加拿大木材工业（经济影响）；并为加拿大人提供更坚固、可持续的材料制造和防火的大型木结构建筑（社会影响）。