Abstract With the span of steel truss girder cable-stayed bridge (STGCB) increases, it is easy to have local stability problems caused by the increase of axial forces, and the whole steel truss girder uses a large amount of steel. To solve these problems, a new laminated girder single tower cable-stayed bridge (NLGCB) is proposed in this paper. The structure of NLGCB is similar to STGCB, the difference is that the lower chords of the main girder near the cable tower are changed into the concrete structure, while the web members and upper chords are made of steel. Thus, a new type of concrete-steel laminated girder is formed, so as to improve the stress characteristics of the main girder. In order to verify the superiority of mechanical properties of NLGCB, a test bridge with an unequal span (5?m?+?6?m) was constructed. The natural frequency of the first in-plane vibration of the bridge was measured by the pulsation test, and the stresses and deflections of the structure were tested by the static load test. The static and dynamic characteristics of a 300?m?+?300?m span bridge were analyzed by finite element software and compared with STGCB. The results show that the natural frequency of the first in-plane vibration of the structure is close to the calculated value, and the vibration modes are consistent with the finite element simulation ones. When the steel consumption is reduced by 13.7 and the concrete consumption is not much, the strength, stiffness, natural vibration frequency, and stability of the structure are greatly improved.
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