【摘要】 研究目的:根据主动控制的理念,以东平水道特大桥为依托,对三主桁钢桁拱桥的整个施工过程进行有限元理论计算和分析,确定各施工阶段控制目标,预先分析施工中各控制目标偏离的可能性,并拟订和采取各项预防性措施,采取主动控制措施,指导施工架设,以使该桥顺利建成并满足设计要求。研究结论:通过有限元理论计算和分析,确定各施工阶段的目标控制值,得到扣索索力、支点顶落量、后锚力与压重的可调范围,做到"预先控制";再根据现场监测结果,采取钢桁杆件预抬、扣索张拉、后锚索张拉、边跨钢梁临时压重和支点顶落与纵移的主动控制对策和措施,及时调整结构内力与线形,做到"过程控制";最后全桥成功合龙。更多还原

【Abstract】 Research purposes: In accordance with the active control concept,and in combination with construction of the main bridge of the Dongpingshuidao Bridge,the whole constraction stages of the steel truss arch bridge with three main trusses was calculated and analyzed with finite element theory,the objective control value of every stages was determined,the possibility of deviation from the construction control target was analyzed in advance and the the preventive and active control measures were worked out and taken for guiding the bridge erection to complete the bridge construction smoothly and meet the design requirements. Research conclusions:The theoretical calculation and analysis with the finite element method were carried out for the bridge and the objective control values of every construction stage were determined to obtain the adjustable ranges of the cable force of the buckle cables,the jacking and lowering amount at the support points,the scale of post anchor force and the amount of the counterweight for the side span steel girder to achieve the "pre-control".According to the in-situ monitoring values of the geometry,internal force and cable force during the construction,the active control strategies and measures of pre-raising the steel truss members,tensioning the buckle cable and the post anchor cable,temporarily loading the side span steel girder and jacking,lowering and vertical moving the support point were taken to timely adjust the internal force and geometry of the structure for realizing the "process control" to achieve the successful closure of the bridge.更多还原