腹板两侧部分填充混凝土新型预制组合梁受弯性能试验研究

Experimental research on flexural performance of new precast composite beam partially encased concrete on both sides of web

为探讨腹板两侧部分填充混凝土新型预制组合梁的受弯性能,制作两个新型预制组合梁试件和两个对比梁试件,对比梁分别为工字钢梁和传统部分外包混凝土组合梁。通过改变新型预制组合梁翼缘内侧填充混凝土厚度,研究其裂缝分布、荷载-应变变化规律和受弯承载力。结果表明:腹板两侧部分填充混凝土新型预制组合梁具有较好的受弯承载力,改变翼缘内侧填充混凝土厚度对组合梁极限承载力的影响不显著;新型预制组合梁与传统部分外包混凝土组合梁相比,在不降低组合梁屈服承载力和极限承载力的同时,混凝土用量和组合梁自重分别降低了63.5%和50.67%,具有良好的经济效益。基于试验结果,提出了新型预制组合梁截面受弯承载力计算公式,公式计算值与试验值吻合良好。

In order to explore the flexural performance of a new precast composite beam partially encased with concrete on both sides of the web,two new precast composite beams and two control beams were fabricated.Control beams are I beams and traditional partially encased concrete composite beams.By changing the thickness of the concrete inside the flanges of the new precast composite beams,the crack distribution,changing rules of load-strain curves and flexural capacity were analyzed.The results show that the new precast composite beams partially encased with concrete on both sides of the web have good flexural capacity.The changes of the thickness of concrete have little effect on the ultimate bearing capacity of composite beams.Compared with the traditional partially encased concrete composite beam,the new precast composite beam has similar yield and ultimate bearing capacities.The concrete consumption and the self-weight of the composite beam reduced by 63.5%and 50.67%,which has good economic benefits.Based on experimental analysis,a formula for calculating the flexural capacity of the new precast composite beams was proposed,and the formula calculated value is in good agreement with the experimental value.