蒸压加气混凝土砌体构件抗爆与加固评估系统研究

Autoclaved aerated concrete (AAC) has been widely used in over 40 countries around the world. It can be used to make unreinforced masonry units such as blocks and infill walls, and reinforced elements for factory and civil structures such as wall panels, floor panels, roof panels, lintels, beams and other specially shaped elements. On the other hand, terrorism or gas explosions often result in severe damage or even progressive collapse of civil structures. Researches about AAC are mainly focused on the mechanical properties of the material and structural elements under static actions and AAC structures subjected to seismic loads. Till now there has been extremely limited understanding of the mechanical properties of the AAC material under dynamic load and the structural performance exposed to blast load. The present research program will start with studying the dynamic properties of AAC material and provide in-depth investigation on the response and damage mechanisms of AAC masonry elements under blast load based on experimental, numerical and theoretical analyses. Furthermore, the project will investigate the possible strengthening methods and generate pressure-impulse curves for quick damage assessment of un-strengthened and strengthened AAC masonry elements. The project aims at providing theoretical support for relative research and workable solution for engineering applications.

蒸压加气混凝土材料已在全球40多个国家普遍应用于建造无筋砌筑型单位如砌体材料、填充墙等，也可应用于工业厂房和民用建筑的配筋砌体构件如墙面板、楼板、屋面板、门窗过梁、梁构件和其他特殊形状构件等。另一方面，恐怖爆炸或燃气爆炸往往对民用建筑造成严重损毁，甚至结构的连续倒塌。目前学术界针对蒸压加气混凝土的研究局限于材料与构件的静力学特性和结构的抗震性能，针对蒸压加气混凝土材料动态特性和砌体构件抗爆的研究成果寥寥无几。本项目拟由蒸压加气混凝土材料的动态力学特性入手，运用试验研究结合数值模拟、理论分析等手段，深入研究蒸压加气混凝土砌体构件在爆炸荷载下的动力响应特征与破坏机理，建立构件抗爆损伤快速评估系统，有针对性地提出构件加固原理与方法，为蒸压加气混凝土结构抗爆分析提供必要的理论支持与工程实用方法。

蒸压加气混凝土（AAC）是一种具有均匀细密气孔的建筑材料，具有保温、轻质、减震、吸能等优点，已在全球40多个国家广泛应用于砌体构件如填充墙或其他非结构构件如墙板、楼板等。与结构构件相比，非结构构件因为强度较低，在遭受爆炸等极端荷载时更加脆弱。此外非结构构件通常由脆性材料制成，极易产生碎片，威胁其他结构及人员安全。为了更好地保护人员与设施安全，深入了解AAC材料的动态力学特性、评估AAC砌体构件的抗爆性能显得尤为重要，而目前学术界在该领域的研究成果寥寥无几。本项目针对B05与B06级AAC，分别开展了拟静力与动态冲击试验，给出了不同密度等级AAC材料的动态力学特性。分别开展了野外燃气爆炸试验与TNT爆炸试验，通过数值模拟验证了材料模型的正确性。通过大量的数值模拟，综合考虑了AAC砌体墙的密度、尺寸、边界条件等因素，给出了对应墙体不同损伤程度的超压冲量曲线，以快速评估AAC砌体墙在爆炸荷载作用下的响应与损伤程度。针对FRP加固与聚脲加固砌体墙，进行了不同加固方法下的参数敏感性分析，考虑了不同加固层厚度、强度等因素，通过大量数值模拟量化了不同加固方法对砌体墙抗爆性能的提升效果，给出了加固AAC砌体墙的超压冲量曲线。本项目建立了AAC砌体墙抗爆损伤快速评估系统，提出了有针对性的加固方法，研究成果同样适用于其他同类多孔混凝土材料，为多孔轻质混凝土结构的抗爆分析提供了快速参考与实用的工程加固方法。