针对内置钢构架型钢混凝土深梁力学性能优越,但是外包混凝土裂缝宽度不能满足正常使用限值的情况,为了有效控制外包混凝土的裂缝开展,对基于裂缝控制的型钢混凝土深梁设计方法进行了研究。基于软化拉-压杆模型建立了内置钢构架型钢混凝土深梁的剪切力学模型,讨论了基于裂缝控制的内置钢构架型钢混凝土深梁设计方法,给出不同裂缝控制要求的箍筋和腰筋面积以及型钢混凝土斜压柱的几何参数;讨论了型钢混凝土斜压柱破坏状况,并给出控制型钢混凝土斜压柱破坏的含钢率条件;给出内置钢构架型钢混凝土深梁发生适筋破坏的条件,为建立该新型内置钢构架型钢混凝土深梁抗剪承载力设计规范公式提供理论基础。
Although the mechanical behaviors of steel truss reinforced concrete (STRC) are advanced, the crack widths of wrapped concrete can not always meet the crack limit. Therefore, in order to control crack development of concrete effectively, the design method of reinforced concrete deep beams based on cracks control is studied. In the paper, based on the softened strut-and-tie model, shear mechanical model of STRC deep beam was developed and the design method based on cracks control was discussed. Stirrups, web reinforcements and design parameters of steel reinforced concrete (SRC) diagonal strut were determined corresponding to different requirements of cracks control; failure modes of SRC diagonal strut were studied and ratio of steel was obtained to control failure of SRC diagonal strut ; design condition of ductile failure of STRC deep beam with reasonable ratio of reinforcements is given, all provide theoretical foundation for establishing shear strength design of STRC deep beam in design codes.