SFRC/SCC钢筋复合梁受弯性能试验研究

设计了一批受拉区为SFRC、受压区为SCC的钢筋复合梁,分析了纵筋配筋率、SFRC替换层钢纤维体积掺量以及替换层高度对复合梁在四点弯曲荷载作用下的承载力、挠度以及裂缝形态的影响,并与普通混凝土梁进行了对比。通过理论分析计算得出了SFRC/SCC复合梁的承载力表达式,并将理论计算结果与试验数据进行了对比分析,以验证表达式的合理性。结果表明:配筋率是提升复合梁承载力的首要因素,1.32%配筋率相对于0.79%配筋率的极限承载力最大可提升24.1%;钢纤维替换层对复合梁的承载力提升并不明显,但对于复合梁的挠度与裂缝宽度控制有明显作用,将替换层高度由50 mm提升至150 mm时,复合梁的挠度和主裂缝宽度最大分别降低了9.2%和77.81%。

Experimental Study on the Flexural Performance of SFRC/SCC Reinforced Composite Beams

A batch of reinforced composite beams with SFRC tension zone and SCC compression zone were designed,and the effects longitudinal reinforcement ratio,SFRC replacement layer steel fiber volume content and replacement layer height on the bearing capacity,deflection and crack shape of composite beams under the four-point bending load were analyzed,and compared with ordinary concrete beams.Through theoretical analysis and calculation,the expression of the bearing capacity of SFRC/SCC composite beams was obtained,and the theoretical calculation results were compared with the experimental datas to verify the rationality of the expression.The results show that the reinforcement ratio is the primary factor to improve the bearing capacity of composite beams.Compared with the reinforcement ratio of 0.79%,the ultimate bearing capacity can be increased by 24.1%at the maximum reinforcement ratio of 1.32%.The steel fiber replacement layer does not significantly improve the bearing capacity of composite beams,but it has an obvious effect on the deflection and crack width control of composite beams.When the replacement layer height is increased from 50 mm to 150 mm,the deflection and main crack width of composite beams are reduced by 9.2%and 77.81%respectively.