表面内嵌纤维筋加固混凝土梁破坏模式研究

THE FAILURE MODES OF CONCRETE BEAMS STRENGTHENED WITH NEAR SURFACE MOUNTED FRP BARS

摘要: 为研究不同参数下表面内嵌纤维筋加固后T 形混凝土梁的破坏模式, 对5 根不同梁端锚固、FRP(fiber reinforced polymer) 筋表面特征和FRP 筋类型的T 形混凝土梁进行受弯性能试验. 结果表明, 无梁端锚固、光圆GFRP (glass fiber reinforced polymer) 筋和CFRP (carbon fiber reinforced polymer) 筋加固梁试件发生粘结破坏. 梁端锚固和FRP 筋表面特征影响加固梁试件的极限载荷, CFRP 筋加固梁试件的屈服载荷和极限载荷较大. 螺纹FRP 筋和有梁端锚固加固梁试件FRP 筋利用率较高. 因此, 有梁端锚固的表面内嵌螺纹GFRP 筋加固是最为有效的加固方式.

Abstract: Focusing on the failure modes, 5T concrete beams with different anchorages, surface characters, materials of FRP bars, strengthened with near surface mounted FRP (fiber reinforced polymer) bars, are used in flexural experiment. It is shown that the bonding failure happens in the strengthened beams without anchorage, and those with plain GFRP bars and CFRP bars. The ultimate load is influenced by anchorage and surface characters of FRP bars; the yield load and the ultimate load are larger in beams strengthened with CFRP bars. The coeficient of utilization of FRP bar is larger for beams strengthened with ribbed FRP bars and anchorage. Therefore, it is most effective to strengthen beams with ribbed GFRP bars and anchorage.