设计了6根不同几何尺寸的中部带有短柱的高强混凝土梁式试件,进行受弯性能低周反复荷载试验,研究试件截面高度对反复荷载作用下高强混凝土梁受弯性能的影响。试件截面高度和上部纵向钢筋配筋率不同,截面长宽比、剪跨比、底部纵向钢筋配筋率和配箍率等参数相同。采用C70高强混凝土,纵向受力钢筋采用HRB400级钢筋。分析了截面高度对高强混凝土梁名义开裂弯矩、名义屈服弯矩、名义极限弯矩、位移延性、塑性转动能力、刚度退化以及耗能能力的影响。研究结果表明:截面高度对高强混凝土试件的名义开裂弯矩、名义屈服弯矩、名义极限弯矩没有明显影响;反复荷载作用下试件刚度退化明显,各试件刚度退化规律相差不大,不受截面高度影响;随着截面高度增加,位移延性系数、塑性铰区的塑性转动能力及功比指数降低,存在明显的尺寸效应。 Six high-strength concrete beam specimens with short columns in the middle of different geometrical dimensions were designed and tested by low-cycle cyclic loading tests. The effect of the specimen section height on the flexural behavior of high-strength concrete beams under repeated loadings was studied. The cross section height of the specimen and the longitudinal reinforcement ratio in the upper part are different, and the parameters of the section length-width ratio, shear span ratio, bottom longitudinal reinforcement ratio and stirrup ratio are the same. Using C70 high-strength concrete, longitudinal force using reinforced HRB400 steel. The effect of cross section height on nominal cracking moment, nominal yield moment, nominal ultimate bending moment, displacement ductility, plastic rotational ability, stiffness degradation and energy dissipation capacity of high strength concrete beams was analyzed. The results show that the section height has no obvious effect on the nominal cracking moment, the nominal yield moment and the nominal ultimate bending moment of high-strength concrete specimens. The stiffness degradation of specimens under repeated loading is obvious, Not affected by the height of the section. With the increase of the section height, the displacement ductility coefficient, the plastic rotation ability and the work ratio index of the plastic hinge area decreased, and the obvious size effect existed.