CAJ | 학술논문

马鞍山长江大桥左汊主桥为（360＋2×1080＋360） m 三塔两跨悬索桥，加劲梁为流线型扁平钢箱梁，采用塔梁固结体系。研究确定采用4台跨缆吊机，从两主跨跨中往桥塔方向进行钢箱梁节段吊装。采用有限元法建立平面杆系模型，进行合龙仿真计算，得到不同条件下合龙所需牵拉力，根据该结果进行牵引预偏系统设计，经方案比选确定采用千斤顶牵引已吊装梁段预偏的方案实现合龙。合龙施工时，在上、下游塔肢各配1台300 t 千斤顶，每台配12束φs 15．2高强度低松弛预应力钢绞线，在塔柱位于桥面以上的人孔内插入悬挑梁，作为千斤顶支撑座；跨缆吊机垂直起吊合龙段，至其顶与已吊装梁段底之间的净距在20～30 cm 时，利用牵引预偏系统牵引梁段，增大合龙空间，完成合龙段施工。
마안산장강대교좌차주교위（360＋2×1080＋360） m 삼탑량과현색교，가경량위류선형편평강상량，채용탑량고결체계。연구학정채용4태과람조궤，종량주과과중왕교탑방향진행강상량절단조장。채용유한원법건립평면간계모형，진행합룡방진계산，득도불동조건하합룡소수견랍력，근거해결과진행견인예편계통설계，경방안비선학정채용천근정견인이조장량단예편적방안실현합룡。합룡시공시，재상、하유탑지각배1태300 t 천근정，매태배12속φs 15．2고강도저송이예응력강교선，재탑주위우교면이상적인공내삽입현도량，작위천근정지탱좌；과람조궤수직기조합룡단，지기정여이조장량단저지간적정거재20～30 cm 시，이용견인예편계통견인량단，증대합룡공간，완성합룡단시공。
The left main bridge of Maanshan Changjiang River Bridge is a three-tower suspen-sion bridge with two main spans and with span arrangement of (360 + 2 × 1 080 + 360) m .The stiffening girder adopts the sleek flat steel box girder which is fixed with the towers .According to the preliminary study ,four cable cranes should be employed to hoist and erect the steel box girder sections from the midspan of the two main spans towards the towers .The finite element method was used to establish the link element model of the bridge to do closure simulation calculation , based on which the required dragging forces for the closure under different conditions were ob -tained .The dragging and pre-offset setting system was designed in accordance with the calculation results .By scheme comparison and selection ,the jacks were used to drag the already-erected gird-er sections to gain the pre-offset for the main girder closure .During the closing process ,a 300 t jack was installed to each of the upstream and downstream tower legs .Each jack is equipped with 12 nos .φs 15 .2 high-strength low-relaxation prestressing steel strands .Overhanging beams are in-serted into the manholes in the tower legs above the bridge deck to form the supporting seats of the jacks .The cable cranes hoisted the closure section vertically ,when the net distance from the top of jacks to the bottom of the already-hoisted girder section was 20 ~ 30 cm ,the dragging and pre-off-set setting system was used to drag the girder sections and widen the closure space to complete the closure section construction .