The Internal Force Analysis Of The Cable-stayed Bridge With Twist Cable-plane And Back Stay In Different Angles Of The Oblique Tower

After the appearance of cable-stayed bridge，it conquered most of bridge designers,constructors and the general public with its elegant appearance, and the completed bridgesoften became local famous landmarks. As repeated beauty will cause aesthetic fatigue,bridge designers have been chasing more beautiful, more innovative bridge, and alsotrying to combine structure stiffness with human aesthetic feeling. With the time passing,the inclined tower cable-stayed bridge emerged. The cable-stayed bridge with an obliquetower and space twist cable plane like saddle and bake cable formed by inclined tower andspace pinch plane inhaul cable makes full use of human visual illusion, so as to bring us astrong visual impact, and it is one of the popular bridges in the construction of urbanbridge currently. But research about the skew angle of the inclined tower, which is one ofthe key questions of this kind of bridge, is not thorough. So this paper has studied theabove problem from the following several aspects.Taking one single pillar inclined tower space pinch plane inhaul cable-stayed bridgein the north as background, the finite element software MIDAS/CIVIL as platform and6°as a range difference, we analyze the stress of the bridge in different angle and differentload condition, and compare the displacement, internal stress of the key section. Itindicates that when the angle approaches90°, which is the appropriate skew angle of theinclined tower, the stress of the whole bridge is balanced and reasonable and thedisplacement is small.At the same time, considering the great threat of the bridge instability, the stability ofthe bridge in different angles is analyzed. Based on the MIDAS/CIVIL model built above,the buckling analysis of the completed bridge in different angles is done. We also comparethe stability coefficient of the tower and the girder in different angles and do research onthe relation of the stability coefficient and the angle. In the same angle, the stabilitycoefficient of the inclined tower is lower than that of the girder. As the angle increases, thesafety factor of the tower and the girder has a downward trend, but is far larger than the specification requirement. So for stability, the skew angle of the inclined tower should notbe too big.After comprehensive analysis of the station of the stress and stabilization, the angleof the tower should approach90°.