关键词: 超大跨径, 部分地锚, 交叉索斜拉桥, 概念设计

Abstract: This paper presents an original design scheme of super-span cable-stayed bridge，namely，a cable-stayed bridge with partial ground-anchorage and cross stays，which is appropriate for cable-stayed bridges with main span length around 1500 m． Its main characteristic is that the long stays cross with each other and are anchored in the ground-anchorage，and thus the long stays result in little horizontal pressure force in the main girder． Studies show that the proposed novel cablestayed bridge system has the following significant advantages over conventional ones: ① Horizontal pressure forces in the main girder caused by cables are greatly reduced; ② The cross stays effectively increase the stiffness of the girder in the span-center region of the main span; ③ As the cross stays can provide dual vertical supports and balance horizontal forces with each other perfectly，the horizontal angle of long stays can be reduced and the height of tower be decreased to only about 1 /5． 5 of main span length as a result; and ④The long stays form a network in the span-center region of the main span， which effectively improve the aerodynamic performance of the long stays．

Key words: super-span, partial ground-anchorage, cable-stayed bridge with cross stays, conceptual design