表面内嵌纤维筋加固混凝土T形梁的受弯性能

Flexural performance of concrete T-shaped beams strengthened with near surface mounted FRP bars

通过对10根不同参数设置下的混凝土T形梁进行受弯试验,研究表面内嵌纤维(fiber reinforced polymer,FRP)筋加固后混凝土T形梁的受弯性能。结果表明:FRP筋表面特征影响加固梁的破坏形态,对极限荷载和FRP筋应变影响显著;钢筋配筋率和FRP筋直径对屈服荷载及极限荷载影响显著,而混凝土强度等级对其基本没有影响;混凝土强度等级、钢筋配筋率和FRP筋直径对加固梁FRP筋应变基本没有影响。推导出表面内嵌FRP筋加固混凝土T形梁受弯承载力计算公式,并结合试验结果,利用二元线性回归法对公式中的折减系数进行了修正。

To investigate the flexural performance,10 T-shaped concrete beams with different parameter settings,strengthened with surface-embedded FRP（ fiber reinforced polymer） bars,were studied in flexural experiment. The results show the failure modes are influenced by surface characters in FRP bars,which has significant influence on ultimate capacity and strain in FRP bars. The reinforcement ratio and diameter of FRP bars have significant influence on yield and ultimate capacity,except for the concrete strength. The concrete strength,reinforcement ratio and diameter in FRP bars have no obvious influence on the strain in FRP bars. The calculation formula of flexural capacity in T-shaped concrete beams strengthened with surface embedded FRP bars is derived,and the reduction coefficient in the calculation formula through the results of experiment and the method of binary linear regression is corrected.