中文摘要：

为研究高强钢筋超高性能混凝土（ultra-high performance concrete,UHPC）梁的正常使用性能,对6根UHPC梁进行了正截面弯曲性能试验,总结高强钢筋UHPC梁的荷载-挠度变化规律,研究其开裂弯矩、短期刚度、裂缝宽度及相应的计算方法。以《混凝土结构设计规范（GB 50010-2010）》为基础,根据试验结果回归出高强钢筋UHPC梁开裂弯矩的截面抵抗塑性影响系数表达式,确定了高强钢筋UHPC梁的钢筋应变不均匀系数、开裂截面内力臂系数和平均综合应变系数,从而得出高强钢筋UHPC梁短期刚度的计算公式,并按钢纤维混凝土计算方法对梁的短期刚度进行了修正计算和对比分析,为实际工程应用提供依据。

英文摘要：

To study the serviceability of ultra-high performance concrete（ UHPC） beams reinforced with high strength steel bars,the flexural properties of six UHPC beams were tested. Then the change law of load-deflection of the UHPC beam was concluded,the cracking moment,the short term stiffness and cracking width,and the calculation methods were summarized. Based on the code for design of concrete structures（ GB 50010-2010）,the cross sectional plastic coefficient influencing the regression equation of UHPC beam＇s cracking moment was concluded,the rebar nonuniform coefficient of UHPC beam,the internal lever arm coefficient of cracking cross section,and the average integrated strain coefficient were ascertained to calculate the beam＇s short term stiffness. The beam＇s short term stiffness was calculated and compared,based on the adjusted calculating method for steel fiber reinforced concrete. In addition,a modified cracking width calculation formula was generated.