不同纵筋率高强钢筋RPC梁抗剪承载力及剪切延性试验研究

为研究纵筋率对高强钢筋活性粉末混凝土梁剪切性能的影响,进行集中荷载下5根RPC梁的受剪试验,分析纵筋率对梁的斜裂缝宽度、剪切延性及抗剪承载力的影响。结果表明:试验梁的抗剪承载力随着纵筋率的提高而提高,而剪切延性随着纵筋率的提高而降低;采用高强钢筋的活性粉末混凝土梁,正常使用极限状态下斜裂缝最大宽度不超过0.3 mm。建立考虑纵筋作用的高强钢筋活性粉末混凝土梁抗剪承载力计算的经验公式,利用经验公式对搜集的27根梁进行计算,吻合较好且变异系数小。该公式具有一定的参考意义,可为高强钢筋活性粉末混凝土梁抗剪承载力的研究提供参考。

Experimental Study on Shear Bearing Capacity and Shear Ductility of High Strength Reinforced RPC Beams with Different Longitudinal Reinforcement Ratio

In order to study the effect of the longitudinal reinforcement ratio on the shear performance of high-strength reinforced reactive powder concrete beams, shear test of 5 RPCbeams under concentrated load is conducted to analyze the effect of longitudinal reinforcement ratio on diagonal crack width,shear ductility and shear capacity of beams. The results show that the shear bearing capacity of test beam increases with the increase of longitudinal reinforcement ratio,and the shear ductility declines with the increase of longitudinal reinforcement ratio; the maximum diagonal crack width is less than 0. 3 mm in serviceability limit states of high strength reinforced reactive powder concrete beams without stirrups. The empirical formula for calculation of shear capacity of high strength reinforced reactive powder concrete beam is established considering the contribution of the longitudinal reinforcement. The calculation with the presented method of the data collected from 27 beam agree well with the test values with small variation coefficient and the formula is of certain reference and can facilitate the study of the shearing capacity of high strength reinforced reactive powder concrete beams.