爆炸作用下BFRP-FRCM加固砌体填充墙破坏机理和评估方法研究

The damage of the masonry infill walls under the blast loading is serious, and the blast-resistant design of masonry infill walls become a hot topic. From the microcosmic and macroscopical analysis, the blast performance of the BFRP-FRCM reinforced masonry infill walls will be systematically studied by means of theoretical analysis, experimental research and numerical simulation. The dynamic performances of the BFRP mesh, FRCM and BFRP-FRCM composite layer will be revealed, and a BFRP-FRCM composite layer model considering strain rate effect will be set up. A static and dynamic bond-slip constitutive model on the interface of the BFRP mesh and FRCM, the interface of the BFRP-FRCM and masonry infill walls will be established. Bond-slip mechanism of the interfaces between different materials of the BFRP-FRCM composite layer reinforced masonry infill walls will be revealed. The failure modes of the BFRP-FRCM reinforced masonry infill walls under blast loading will be studied, and effect rules of composite layer parameters influencing blast-resistance properties of masonry infill walls will be set up. The blast-resistance reinforcement mechanism of the BFRP-FRCM on masonry infill walls will be revealed. The blast-resistance performance evaluation and blast-resistance design method of the BFRP-FRCM strengthened masonry infill walls will be established, and the achievements could become the basis for the safety protection of masonry infill walls.

爆炸荷载作用下砌体填充墙的破坏严重，抗爆加固设计问题突出。本项目从微观和宏观两个层面，运用理论分析、试验研究、数值模拟等方法对BFRP-FRCM加固砌体填充墙抗爆加固机理进行系统研究。项目将研究BFRP网、FRCM以及BFRP-FRCM复合层的动态性能，建立考虑应变率效应的BFRP-FRCM复合层材料模型；建立BFRP网与FRCM界面、BFRP-FRCM与砌体填充墙界面的静态、动态粘结滑移本构模型；揭示BFRP-FRCM复合层加固砌体填充墙不同材料界面之间的粘结机理；确定爆炸荷载作用下BFRP-FRCM加固砌体填充墙的破坏模式，建立复合层加固参数对砌体填充墙抗爆性能的影响规律，揭示BFRP-FRCM加固砌体填充墙的抗爆加固机理；建立BFRP-FRCM加固砌体填充墙的抗爆性能评估方法和抗爆设计方法，为砌体填充墙的抗爆安全防护提供依据。

BFRP(Basalt Fabric Reinforced Polymer)网格作为一种新型增韧、阻裂材料，具有轻质高强、绿色环保、无磁性等优势。FRCM(Fiber Reinforced Cementitious Matrix)凭借其高抗拉应变及耗能能力，被广泛应用于桥梁、道路、既有结构加固修复等工程中。将FRCM与BFRP网格组合形成的复合加固层具有耐高温、耐腐蚀潮湿、兼容性强、黏结强度高等优点。为了探讨该材料的综合性能及应用前景，本项目对BFRP-FRCM加固混凝土构件的破坏机理和性能评估等进行了系统研究。首先，通过静力拉伸试验，研究FRCM砂浆种类、玄武岩网格配网率、水胶比对BFRP-FRCM复合层的静态拉伸力学性能的影响。通过四点弯曲试验，探究不同种类FRCM、不同水胶比、不同配网率对复合层抗弯强度、最大挠度、弯曲韧性指标的影响；通过霍普金森拉杆研究所掺纤维种类及加载速率、砂浆强度对BFRP-FRCM复合材料动态力学性能的影响规律；其次，为了研究BFRP-FRCM复合层与加气砌块之间的黏结性能，开展了水泥基材料内掺纤维种类、复合层黏结长度和BFRP纤维网层数的单面剪切试验。通过抗压试验与抗折试验，探究纤维取向、纤维种类和纤维布置位置等因素对定向纤维增强水泥基材料的抗压与抗折性能的影响规律。最后，通过野外现场爆炸试验，对爆炸荷载作用下BFRP-FRCM复合层加固砌体墙的爆炸破坏机理进行了系统研究，给出了该加固技术抗爆加固机理，并对爆炸后的砌体墙进行了损伤评估。上述研究结果为该材料在结构加固领域的推广应用提供基础理论和试验依据。