基于MCFT理论的钢纤维混凝土梁的截面分析

根据钢纤维混凝土的特性,对MCFT理论的裂后混凝土平均主应力-平均主应变关系进行了修正。在Vecchio和Collins对钢筋混凝土板在纯剪作用下截面分析的基础上,叠加了弯矩的作用,建立了钢纤维混凝土梁在弯剪复合作用下的截面分析模型。利用作者以及其他研究者的试验对该模型进行了验证,结果表明计算得到的钢纤维混凝土梁的剪力-箍筋应变曲线和极限荷载与实测结果吻合良好。该文还利用该模型对钢纤维和箍筋对梁抗剪性能的影响效率进行了比较。

SECTIONAL ANALYSIS OF STEEL FIBER REINFORCED CONCRETE BEAMS USING MODIFIED COMPRESSION FIELD THEORY

Based on the characteristics of steel fiber reinforced concrete, averaged principal stress-strain relationships for cracked concrete of modified compression field theory (MCFT) are modified. Then a new sectional analytical model for steel fiber reinforced concrete beams under the combined action of bending moment and shear is established by adding the bending moment action into the model of Vecchio and Collins, a sectional analysis model for reinforced concrete membrane element under pure shear. The new model is tested by the experiments of the authors and other researchers. Computing predictions for the ultimate load and the dependence between shear and strain of stirrup of steel fiber reinforced concrete beams obtained by the model show a good agreement with their practically observed counterparts. The efficiency of steel fibers and stirrups improving shear behavior of the beams are also compared through the new model.