中文摘要：

研究配制最大力总伸长率大于9%的600 MPa级新型高强抗震钢筋的混凝土梁的抗裂性能。进行了不同混凝土强度等级（C30、C40、C50、C60）和不同钢筋强度等级（335、400、600 MPa）的钢筋混凝土梁抗裂度的系统试验,结果表明：钢筋强度的增加对混凝土抗裂性能提高有限,混凝土强度仍是影响抗裂的重要因素。通过开裂弯矩试验值与GB 50010、JTJ 267、DL/T 5057等现行规范计算值的详细比较分析可知：现行各混凝土设计规范中,对于混凝土强度fcu≥50 MPa的情况,其计算值都高于实测值较多,即现行规范高估了强度等级为C50以上的钢筋混凝土梁的抗裂性能,其设计抗裂安全性偏低。由此,基于试验实测数据,给出了钢筋混凝土梁抗裂度的修正公式,其与试验结果吻合良好。

英文摘要：

The resistance against cracking of reinforced concrete beams with 600 MPa seismic steel bar were studied,in which the per-centage total extension at maximum force of 600 MPa seismic steel bar is larger than 9%.The systematic experimental research was carried out,linked to the different concrete strength（C30,C40,C50,C60）and different steel strength（335,400,600 MPa）were all considered.The results show that the increasing of steel strength is useless for improver the resistance against cracking of reinforced concrete beams and the concrete strength is the most important factor.According to the results of comparison between experimental data and the calculation values by current code GB 50010,JTJ 267 and DL/T 5057,it was found that the safety degree is lower when compress strength of concrete fcu≥50 MPa.Therefore,based on experimental data,the improved calculating formula was proposed.It show that the calculated value by proposed formula and the experimental value accord well.