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为改善波形钢腹板组合梁负弯矩区受力性能,避免波形钢腹板剪切屈曲以及受压翼缘局部屈曲,提出波形钢腹板内衬混凝土形成组合构造的措施。通过设计具有不同弯、剪比参数的2个试件,开展波形钢腹板内衬混凝土组合梁模型试验,研究其承受弯矩与剪力共同作用下的力学性能,明确不同弯、剪比对极限承载能力以及失效模式的影响,建立弯、剪共同作用的相关方程。试验结果表明:试件的破坏模式为明显的弯、剪耦合破坏,内衬混凝土出现弯曲、剪切2类主裂缝;弯剪比对试件未开裂截面抗剪刚度影响较小,但对初始开裂后试件抗剪刚度影响较大;弯剪比增大,试件开裂荷载减小,结构的延性增加;在弯、剪共同作用下,未开裂截面应变基本满足平截面假定,但受拉区混凝土开裂后,相应区域波形钢腹板由于“折叠效应”应变较小,平板段几乎为0,斜板段由于混凝土的挤压作用应变不为0。最终依据模型试验与数值模拟结果,建立弯、剪共同作用下波形钢腹板内衬混凝土组合梁承载力评价准则,为今后的设计提供参考。
In order to improve the mechanical behavior of the negative bending moment zone of the corrugated steel web composite beam and to avoid the shear buckling of the corrugated steel web and the local buckling of the compression flange, the measures to form the combined structure of the corrugated steel web-lined concrete are proposed. By designing two specimens with different parameters of bending and shear, the model test of corrugated steel web-lined concrete composite beam was carried out to study the mechanical properties of the composite beam subjected to bending moment and shear stress. Ultimate bearing capacity and the impact of failure mode, the establishment of bending, shear related equations. The test results show that the failure modes of the specimens are obvious bending and shear coupling failure, and the two types of main cracks are bent and sheared. The shear-bending ratio has little effect on the shear stiffness of the uncracked section. However, The shear stiffness of the specimen after cracking has a greater impact; the shear-shear ratio increases, the specimen cracking load decreases, the ductility of the structure increases; under the combined action of bending and shearing, the strain of the uncracked section basically satisfies the assumption of flat section, After cracking of the concrete in the area, the corrugated steel webs in the corresponding area have a small strain due to the “folding effect” and almost zero in the flat area, and the strain in the inclined slab due to the compression of the concrete is not zero. Finally, according to the results of model test and numerical simulation, the evaluation criteria for the bearing capacity of corrugated steel web-lined concrete composite beams under the combined action of bending and shearing are established, which will provide references for future design.