Supporting data for Novel FRP reinforced low-carbon calcined clay-based foam concrete

In recent years, foam concrete has become increasingly popular in the field of construction, mainly because it is suitable for sustainable designs of modern buildings, such as eco-sustainability (i.e., reducing CO2 emissions, conserving energy), economic sustainability (i.e., minimizing dead loads for structures, operating with less labor and limiting heat losses), and living comfort (i.e., getting appropriate interior temperature, lowering noise). Moreover, the use of foam concrete in modular integrated construction (MiC) can significantly reduce the weight of the modules, which not only lowers transportation costs and carbon emissions but also reduces the difficulty of on-site installation and the corresponding carbon emissions. However, when considering embodied carbon and energy consumption, conventional ordinary Portland cement foam concrete (OPCFC) presents notable disadvantages. This is attributed to the high embodied carbon and energy content resulting from substantial ordinary Portland cement (OPC) usage. Consequently, reducing the cement content within OPCFC emerges as a critical strategy for advancing low-carbon sustainable development. Clay, which is abundantly available worldwide, has potential to act as an alternative supplementary cementitious material (SCM) for partial OPC replacement. Nevertheless, research on low carbon clay-based foam concrete remains limited. In alignment with the Hong Kong government’s carbon neutrality objectives, this study investigates the properties of a novel FRP reinforced low-carbon limestone calcined clay cement foam concrete (LC3FC), and proposes corresponding theoretical models.This study investigated the possibility of applying the LC2 mixture composed of the widely existing calcined clay with limestone and gypsum to low-density OPCFC. The results showed that partially replacing OPC with LC2 can significantly enhance the sustainability of foam concrete and demonstrate excellent performance in terms of mechanical properties, water resistance, and drying shrinkage performance. In addition, proposing a new reliability-based service life model to evaluate the service lives of LC3FC reinforced by traditional steel bars or BFRP bars. The results indicated that the combined use of LC3FC and BFRP bars substantially extends the service life of foam concrete members.This study explored strategies to further improve the compressive strength, drying shrinkage, and water absorption performance of foam concrete. And a comparative performance analysis was conducted between the developed high-performance foam concrete and foam concrete incorporating conventional SCMs. Furthermore, to assess the elevated temperature performance of LC3FC and to address the poor fire resistance of conventional reinforced concrete structures, elevated temperature performance test was conducted and corresponding theoretical calculation models were proposed.Finally, this study examined the mechanical performance of LC3FC slabs with varying densities reinforced by BFRP and GFRP bars, and further explored the influence of glass fibers (GF) on improving slab behavior. Furthermore, this study presented a theoretical calculation model for the cracking moment and failure flexural moment applicable to foam concrete slabs, and for the first time, proposed a theoretical calculation model for the shear capacity of foam concrete slabs that explicitly incorporates reinforcement characteristics, density, and fiber-related parameters. The results showed that with proper design, construction, and curing, LC3FC slabs have substantial application potential for slab components in MiC.近年来，泡沫混凝土（foam concrete）在建筑领域愈发受到青睐，究其原因，其适配现代建筑的可持续设计需求，涵盖生态可持续性（即降低二氧化碳排放、节约能源）、经济可持续性（即减小结构恒荷载、减少用工量并限制热损失）以及居住舒适度（即维持适宜室内温度、降低噪音）。此外，在模块化集成建造（modular integrated construction, MiC）中使用泡沫混凝土可显著降低模块自重，不仅能缩减运输成本与碳排放，还可降低现场安装难度及对应碳排放。然而，若考量隐含碳与能源消耗，传统普通硅酸盐水泥泡沫混凝土（ordinary Portland cement foam concrete, OPCFC）存在显著缺陷，其根源在于大量使用普通硅酸盐水泥（ordinary Portland cement, OPC）所带来的高隐含碳与高能耗。因此，降低OPCFC中的水泥掺量成为推进低碳可持续发展的关键策略。黏土在全球储量丰富，有望作为替代辅助胶凝材料（supplementary cementitious material, SCM）部分替代OPC。但目前针对低碳黏土基泡沫混凝土的研究仍较为有限。本研究契合香港政府的碳中和目标，针对新型纤维增强聚合物（fiber reinforced polymer, FRP）加固低碳石灰石煅烧黏土水泥泡沫混凝土（limestone calcined clay cement foam concrete, LC3FC）的性能展开研究，并提出了对应的理论模型。本研究探究了将由广泛存在的煅烧黏土、石灰石与石膏组成的LC2混合物应用于低密度OPCFC的可行性。结果表明，采用LC2部分替代OPC可显著提升泡沫混凝土的可持续性，且在力学性能、抗水性与干缩性能方面表现优异。此外，本研究提出了一种基于可靠性的寿命模型，用于评估传统钢筋或玄武岩纤维增强聚合物（basalt fiber reinforced polymer, BFRP）筋加固LC3FC的服役寿命。结果显示，LC3FC与BFRP筋的组合使用可大幅延长泡沫混凝土构件的服役寿命。本研究探索了进一步提升泡沫混凝土抗压强度、干缩性能与吸水性能的策略，并针对所开发的高性能泡沫混凝土与掺入传统辅助胶凝材料的泡沫混凝土开展了性能对比分析。此外，为评估LC3FC的高温性能并解决传统钢筋混凝土结构耐火性能不佳的问题，本研究开展了高温性能试验，并提出了对应的理论计算模型。最后，本研究针对玄武岩纤维增强聚合物（BFRP）筋与玻璃纤维增强聚合物（glass fiber reinforced polymer, GFRP）筋加固的不同密度LC3FC板的力学性能展开测试，并进一步探究了玻璃纤维（glass fibers, GF）对板受力性能的提升作用。此外，本研究提出了适用于泡沫混凝土板的开裂弯矩与受弯破坏弯矩理论计算模型，并首次提出了明确考虑配筋特征、密度与纤维相关参数的泡沫混凝土板受剪承载力理论计算模型。结果表明，通过合理的设计、施工与养护，LC3FC板在MiC的板类构件中具备可观的应用前景。