论文部分内容阅读
通过5根无粘结预应力空腹式钢骨混凝土梁和1根非预应力空腹式钢骨混凝土梁的受弯试验,分析梁截面应变分布、变形、预应力筋内力增量发展及裂缝分布规律。结果表明:在其它参数条件相同的情形下,对空腹式钢骨混凝土梁施加预应力,可显著提高梁的抗裂承载力;以受拉区混凝土开裂和受拉钢骨下边缘屈服为转折点,试验梁的荷载-变形曲线呈三直线特征;破坏形态与非预应力空腹式钢骨混凝土梁相比裂缝出现较迟,裂缝向上开展缓慢,主裂缝特征不明显;建立的无粘结预应力空腹式钢骨混凝土梁的抗裂承载力和极限承载力计算公式与试验结果吻合较好。
Through the bending tests of 5 unbonded prestressed fast-tracked SRC beams and 1 non-prestressed fast-track SRC beams, the analysis of the beam cross-section strain distribution, deformation, increment development of prestressed tendons and the distribution of cracks . The results show that under the same conditions of other parameters, the prestressing force can be applied to the beam of SRBS beam significantly. With the cracking of the concrete in the tension zone and yielding of the lower edge of the tensioned steel sheet as a turning point, The load-deformation curve of the test beam shows a three-line characteristic. Compared with the non-prestressed fast-loaded SRC beam, the failure mode appears later than the non-prestressed SRB beam. The crack propagates upward slowly and the main crack is not obvious. The established unbonded prestressed fasting The formula for calculating the ultimate bearing capacity and ultimate bearing capacity of steel reinforced concrete beams is in good agreement with the test results.