Abstract:Abstract : Research purposes : When the post - construction railway or highway passes through the existing line,the framed structure bridge is one of tlie main forms of changing the plane cross to three - dimensional cross. In the process of jacking construction, the construction parameters and engineering conditions will lead to the geometric changes of track and subgrade of the existing lines,and have a negative impact on safety and stability of the train on the existing lines. Taking the jacking construction of framed structure bridge which is under tlie existing Tinajin - Sanhaiguan railway as research object, by using the MIDAS/GTS finite element software, the jacking construction model of framed construction bridge is established,the parameters which influence jacking effect of frame construction bridge are analyzed, and compared with actual engineering monitoring results, the influence of construction parameters and engineering conditions on the settlement of subgrade,the rail top level and the horizontal displacement of subgrade are discu sed. Research conclusions:( 1 ) Settlement of the operated subgrade is greatly 9fected by the excavation footage, and settlement becomes greater when the excavation footage become bigger. ( 2 ) Settlement of subgrade can be effectively controlled when the grouting strength increased,and the maximum settlement decreases by about 10% for every 10 MPa increase in grouting strength. (3) The jacking force is the main reason for the horizontal displacement of the operated subgrade,and the horizontal displacement increases by about 30% for every 50 MPa increase in jacking force. (4) The settlement of subgrade,the rail top level and the horizontal displacement of subgrade are greatly influenced by the span, depth and elasticity modulus of subgrade filling of the framed structure bridge,and all the three targets increase with the increase of the span and decrease of the depth and elasticity modulus of subgrade filling. (5 ) The research results can provide a reference for tlie design of similar framed structure bridge engineering.
沈宇鹏1,左瑞芳1,杨丽明2,陈万成3,金振山4. 影响繁忙干线框构桥顶进效果的因素分析[J]. 铁道工程学报, 2017, 34(5): 45-51.
SHEN Yu - peng1,ZUO Rui - fang1,YANG Li - ming2,CHEN Wan - cheng3,JIN Zhen - shan4. Research on the Factors Affecting the Busy Operation Lines during Jacking the Framed Structure Bridge. Journal of Railway Engineering Society, 2017, 34(5): 45-51.