BFRP网格改良藏式毛石墙体受力性能试验研究

为研究玄武岩纤维复材 （basalt fiber reinforced polymer,BFRP） 网格改良藏式毛石墙体（简称毛石墙体）的受力性能,分别进行了4片毛石墙体的受压试验及低周水平往复加载试验. 重点研究竖向及水平往复荷载作用下BFRP网格改良毛石墙体的受力行为、破坏形态、承载能力、耗能性能、刚度退化规律等. 试验结果表明:竖向荷载下BFRP网格改良毛石墙体墙身裂缝发展较未改良毛石墙体缓慢,其平均极限抗压承载力是未改良毛石墙体的2.72倍,改良毛石墙体的最终破坏形态为BFRP网格受拉断裂后墙体面外失稳破坏;低周水平往复荷载作用下BFRP网格改良毛石墙体的耗能性能和抗剪承载力较未改良毛石墙体有显著提高,其平均峰值抗剪承载力提高幅度达74.3%;BFRP网格改良毛石墙体的最终破坏形态为斜向贯通裂缝处BFRP网格受拉断裂后墙体的剪切破坏. 

Experiments on Mechanical Performance of Tibetan Rubble Stone Walls Retrofitted with BFRP Grids

Two groups of Tibetan rubble stone walls, each with four pieces, were tested under compressive loading and low cyclic loading, respectively, in order to study the mechanical performance of the walls retrofitted with basalt fiber reinforced polymer (BFRP) grids. These tests focus on the mechanical behavior, failure modes, load carrying capacity, energy dissipation capacity, and stiffness degradation of the walls. The experimental results demonstrate that the rubble stone walls retrofitted with BFRP grids showed slower crack development compared with the un-retrofitted walls under the same compressive load. The measured average compressive strength of the rubble stone walls retrofitted with BFRP grids was about 2.72 times that of the un-retrofitted walls. The typical compressive failure mode of the rubble stone walls retrofitted with BFRP grids was BFRP grids rupture followed by out-of-plane buckling failure. Meanwhile, the rubble stone walls retrofitted with BFRP grids showed higher energy dissipation capacity and shear strength than the un-retrofitted rubble stone walls, and the measured average shear strength increased by 74.3%. Under low cyclic loading the rubble stone walls retrofitted with BFRP grids showed BFRP grids rupture along the diagonal cracks followed by shear failure.