绿色低碳地聚物混凝土材料和结构设计的基础研究

Geopolymer concrete is a composite material made by chemically activated alumino-silicate cementitious binders. It has excellent corrosion and high temperature resistance and performs even better than conventional Portland cement concrete in terms of the mechanical properties. Geopolymer concrete can be produced solely upon the use of alumino-silicate materials that do not need any calcination of the raw materials. The production and usage of geopolymer concrete can lead to a significant reduction in environmental pollution, carbon emission and energy consumption, and therefore, meets the needs of sustainable development of the national economy and construction industry. Nevertheless, there is a lack of systematic research on the theories for design and production of geopolymer concrete, their mechanical constitutive models and the structural design approaches for reinforced geopolymer components. This has heavily impeded the wide use of geopolymer concrete in the construction industry. To fill in the above knowledge gap, this project aims to conduct a systematic research program focusing on three key scientific issues: (1) the mechanisms for the setting and hardening, microstructure development and optimization of geopolymer concrete made by various alumino-silicate materials; (2) the constitutive models of geopolymer concrete under various stress conditions and the design theories for reinforced geopolymer concrete structural components; and (3) the deterioration mechanisms and predictive models of geopolymer concrete exposed to elevated temperature and corrosive environments at both material and structural component levels. Upon the completion of this project, a holistic but in-depth understanding of the behavior and modeling of geopolymer concrete from material to structural levels will be achieved, which will provide solid scientific foundation for the wide applications of geopolymer concrete in sustainable construction in China and the rest of the world.

地聚物混凝土是用以化学激发硅铝酸盐物质形成的胶凝材料制备的混凝土，具有耐腐蚀性好、耐高温等优点，其力学性能甚至优于传统的硅酸盐水泥混凝土。地聚物混凝土可全部利用不再需要高温煅烧的硅铝酸盐废弃物作为胶凝组分，其生产和利用可节能减排，有利于国民经济的可持续发展。但目前关于地聚物混凝土设计和制备的方法、本构关系、结构设计理论等方面的研究非常有限，成为制约地聚物混凝土工程应用的瓶颈。针对上述问题，围绕“不同硅铝酸盐物质配制的地聚物混凝土凝结硬化、微结构形成及性能发展和调控；地聚物混凝土的本构关系及配筋地聚物混凝土构件的设计理论；地聚物混凝土及其配筋构件的高温及侵蚀性环境下的劣化机理及预测模型”三个科学问题展开系统研究，旨在建立地聚物混凝土组成设计方法和本构关系，阐明不同荷载作用下地聚物混凝土构件的强度和变形设计理论，提出地聚物混凝土结构耐久性设计方法，为地聚物混凝土的广泛应用提供坚实的理论基础。

本项目从“不同硅铝酸盐物质配制的地聚物混凝土凝结硬化、微结构形成及性能发展和调控；地聚物混凝土的本构关系及配筋地聚物混凝土构件的设计理论；地聚物混凝土及其配筋构件的高温及侵蚀性环境下的劣化机理及预测模型”三个科学问题展开系统研究。首先研究了激发剂组成和胶凝组分对地聚物混凝土工作性能和力学性能的影响。定量了不同激发剂和不同氧化物组成的胶凝组分对地聚物混凝土相关性能的协同效应，提出了基于原材料组成的凝结时间调控理论和方法；基于紧密堆积和高性能混凝土设计理论，采用五因素四水平的正交设计方法和三角形单一质心设计法，提出有效的地聚物混凝土配合比组成设计理论与方法。在此基础上，研究了地聚物混凝土的基本力学性能，包括抗压、抗弯、静态及动态力学性能，并设计完成了一系列关于钢筋地聚物混凝土构件的试验研究，评估了现有的钢筋混凝土规范对地聚物混凝土配筋构件的适用性，并提出相应的钢筋地聚物结构设计理论。此外，研究了地聚物混凝土的氯离子传输性能和结合能力、碳化反应机理、碱-骨料反应，为研究配筋地聚物混凝土在腐蚀环境中的长期耐久性提供了理论依据及提升手段。通过试验对配筋地聚物混凝土梁、柱构件高温作用下性能随时间退化的全过程进行分析，提出火灾下配筋地聚物混凝土的损伤分析模型。