配置HRBF500钢筋的无粘结预应力混凝土梁短期刚度试验研究

Experimental Study on the Short-term Flexural Stiffness of Unbonded Prestressed Concrete Beams with HRBF500 Steel Bars

通过8根矩形截面梁的受弯试验,研究配置HRBF500纵向钢筋的无粘结预应力混凝土梁短期受弯刚度,并对国家标准《混凝土结构设计规范》(GB 50010—2010)中的刚度计算公式进行了评析。试验研究结果表明:设计规范GB 50010的短期受弯刚度计算模式对配HRBF500钢筋的无粘结预应力混凝土梁仍适用,但按设计规范GB 50010计算的短期刚度总体上比试验值偏小,二者之比平均为0.857。根据试验结果,提出无粘结预应力混凝土梁刚度比值系数ω的修正建议,修正后的计算值与试验值符合较好。

The flexural stiffness of unbonded prestressed concrete beams with HRBFS00 steel bars was studied by lab testing of 8 specimen. The formulae for stiffness estimation in Code for Design of Concrete Structures GB50010-2010 were evaluated. The experimental results show that the original method in GBS0010-2010 is in general suitable for unbounded prestessed concrete beams with HRBFS00 steel bars. However, the calcu-lations of short-term stiffness are generally lower than those testing values with the average ratio of 0. 857. Based on the test results, the unbonded prestressed concrete beam stiffness reduction factor to were modified. The modified values of stiffness are consistent with the experimental results.