GFRP布被动约束标准煤矸石混凝土圆柱轴压性能细观模拟

Mesoscopic Simulation on Axial Compression Performance of Standard Coal Gangue Concrete Circular-Columns Confined by GFRP Sheet

为研究细观模型的有效性,利用三维PFC-FLAC耦合方法构建玻璃纤维增强复合材料(GFRP)布约束煤矸石混凝土圆柱的细观连续-非连续耦合模型。通过已有试验数据验证了该模型的有效性,并在此基础上开展了0、2、4层GFRP布对煤矸石混凝土圆柱的轴压性能、破坏模式及吸能特性的影响研究。结果表明:建立的细观模型精度较高;煤矸石混凝土圆柱的极限破坏强度随GFRP层数增加而逐渐增大,能量吸收效率和体积比吸收能也均有相同的变化趋势,但存在增大比例减小的问题。从应力-应变曲线延性特征、峰值强度、破坏模式、总能量密度变化、能量吸收效率及体积比吸收能等六个方面综合考虑,兼顾经济成本与缠绕水平原则,确定GFRP布层数增加可以增强煤矸石混凝土圆柱的轴压性能。

In order to study the effectiveness of the mesoscopic model,a mesoscopic continuous-discontinuous coupling model of coal gangue concrete circular-columns confined by glass fiber reinforced composite(GFRP)sheet was established by three-dimensional PFC-FLAC coupling method.The validity of the model was verified by experimental data.On this basis,the effects of 0,2 and 4 layers of GFRP sheet on the axial compression performance,failure mode and energy absorption characteristics of coal gangue concrete circular-columns were studied.The results show that the established mesoscopic model has high accuracy.The ultimate failure strength of coal gangue concrete circular-columns increases with the increase of GFRP sheet layers.The energy absorption efficiency and volume specific energy absorption also increase with the increase of GFRP layers,but the proportion of increase decreases.The ductility characteristics of stress-strain curves,peak strength,failure mode,total energy density change,energy absorption efficiency and volume specific energy absorption of coal gangue concrete circular-columns are considered comprehensively,and the increasing layers can enhance the axial compression performance of the coal gangue concrete circular-columns,taking into account the principles of economic cost and winding level.