摘要
试验研究了不同纵向受拉钢筋配筋率的自密实轻骨料混凝土梁和普通钢筋混凝土梁的抗弯性能。结果表明,在同级荷载作用下,自密实轻骨料混凝土梁纯弯段的裂缝分布较普通钢筋混凝土梁均匀,其极限抗弯承载力和截面刚度较小,各试验梁在受力过程中正截面平均应变符合平截面假定;通过增加受拉钢筋配筋率能够有效抑制裂缝的发展、增大截面刚度和提高极限抗弯承载力。提出了自密实轻骨料混凝土梁最大裂缝宽度计算公式,验证了GB 50010—2010《混凝土结构设计规范》中的梁的抗弯极限承载力计算公式适用于本文设计的试验梁,计算结果与试验结果均吻合。
In this paper, the flexural performance tests are carried out on self-compacting lightweight aggregate concrete beams and ordinary reinforced concrete beams with different longitudinal tensile reinforcement ratios. The results showed that the crack distribution of the pure curved section of the self-compacting lightweight aggregate concrete beam is more uniform than that of the ordinary reinforced concrete beam under the same-stage load. Meanwhile, ultimate bending capacity and section stiffness are small, and the average section normal strain in stress process is in accordance with the plane section assumption. By increasing the reinforcement ratio of the tensile steel bars, the development of cracks can be effectively suppressed, the section stiffness can be increased, and ultimate flexural capacity can be improved. In addition,the formula for calculating the maximum crack width of self-compacting lightweight aggregate concrete beam is proposed.It is verified that the calculation formula of the ultimate bearing capacity of the beam in the Code for GB 50010—2010 Concrete Structure Design is applicable to the test beam designed in this paper. The calculated results agree well with the test results.
引文
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