In order to simplify the skewed continuous steel-box girder bridge’s structure in the middle pier and make it easy to manufacture and assemble uniformly in the factory, a new supporting diaphragm arrangement was proposed by setting the bearings of the middle pier at the independent diaphragms. Taking a (30+35) m skew continuous steel-box girder bridge as the engineering background, a model considering girder, pier and pile and a finite shell element model of the whole bridge were established. The structure mechanical characteristics and the transfer of the support reaction were analyzed under the actions of dead and live load, thermal effect, foundation settlement as well as earthquake, and furthermore the structure torsional stiffness was discussed. The results show that the new design plan can meet the force-bearing demand of the structure, and can provide some references for the design of the similar bridges. For the new and original design, the structure support reaction, bending moment, defection, the displacement time history of the bearings and the torsional stiffness are almost the same. The longitudinal girders share the same force and can be seen as the elastic support of the diaphragm both for the new and original design. The structure equivalent stress near the middle pier is less than 35 MPa, and the degree of the stress concentration of the supporting diaphragms in the new design is smaller under the vehicle load compared with the original design.%为简化斜交连续钢箱梁桥在中间墩处结构构造，方便工厂标准化制造，通过将中墩支座支承在独立的横隔板上，提出一种新型支点横隔板设置方式。以某(30+35) m跨线斜交连续钢箱梁为工程背景，建立梁−墩−桩一体化混合有限单元模型和全桥板单元有限元模型，系统分析恒载、竖向活载、温度、基础沉降、地震荷载以及车辆荷载作用下结构受力特性以及支座反力传递规律，并探讨结构的扭转刚度。研究结果表明：所提出的新支点横隔板设置方式满足结构受力要求，可为类似桥梁的设计提供参考；新设计下结构支座反力、弯矩、挠度和桥墩支点位移时程以及扭转刚度等整体受力特性与原设计的基本相同；新设计和原设计中，结构纵梁分担的荷载一致，可作为于支点横隔板的弹性支承；在车辆荷载作用下，结构中支点位置局部等效应力在35 MPa以内，且新设计结构支点横隔板局部应力集中程度比原设计的小。
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