Research On Key Technology Of Construction Settlement Control Of Yingze Street Under Passing Taiyuan Station

The spatial structure of Taiyuan city center is characterized by the circle type of "single center + peripheral industrial and mining groups",and the old city center is particularly prominent in space and function.As an important symbol building in Shanxi Province,the surrounding municipal engineering is not perfect.Yingze Street underpass Taiyuan Station project for the realization of Taiyuan Station railroad east and west through,supplementing the regional network has important strategic significance,this paper through the analysis of Yingze Street underpass Taiyuan Station channel project design general idea,engineering construction conditions and the situation of existing building(structure);analyzes the influence of underpass construction,site peculiarities,underground obstacles,pipeline relocation before construction and other factors on settlement;from the perspective of construction process,the existing track bed reinforcement technology,pipe jacking construction technology,open excavation construction technology,pipe curtain construction settlement control technology and emergency technology were specifically analyzed to condense and summarize the overall settlement control technology of Yingze Street underpass Taiyuan Station project;finally,the settlement monitor verified the settlement of Yingze Street underpass Taiyuan Station construction.overall control key technology of scientific rationality,the main results are as follows:(1)Yingze Street underpass Taiyuan Station project respectively underpass station on the north and south sides.Yingze Street underpass Taiyuan Station project around the existing buildings(structures)complex,complex underground pipelines,road traffic busy,densely populated.The excavation of the foundation pit in construction may cause the collapse of the sidewall of the foundation pit,resulting in geological disasters;construction risk is large,the design should consider reliable reinforcement of existing structures to avoid deformation and settlement of the station,platform and station track(2)Through the use of Finite element numerical analysis method and Peck empirical formula method simulation calculation track settlement value,the existing track and bed settlement reinforcement for the necessity of analysis: steel pipe jacking construction in the maximum settlement of 12.7mm and 14.1mm,respectively,are greater than the relevant provisions of the roadbed settlement control value of 10 mm and line track static control value of 10 mm and the line track static geometry tolerance deviation management value of 11mm;at the same time the construction of the line package channel,canopy pipe pile foundation and canopy surface deformation of the three working conditions for simulation calculations,it can be seen that the calculated settlement to meet the requirements of safety,but in order to minimize deformation,construction needs to strengthen the monitor,and track the grouting.(3)By analyzing the existing railroad line and bed reinforcement settlement control technology from two perspectives: the affected section of the railroad can take the three reinforcement methods: line buckling reinforcement method,grouting reinforcement method and pipe shed reinforcement method;through the existing railroad,column-free canopy,contact network foundation,platform wall,travel bag channel and all kinds of pipeline in the process of topping construction settlement control technology research: first of all,the existing structure foundation should be slurry reinforcement in advance before the topping machine through;Secondly,set construction parameters such as soil bin pressure and digging speed according to the optimized data of the test section to control the soil output and avoid collapse caused by over-excavation;in addition,the digging parameters should be adjusted timely according to the monitor results to ensure the safety of existing line operation.(4)Through the analysis of underpass project open excavation section construction and pipe curtain construction overall settlement control technology: open excavation section construction overall technology includes three construction techniques: work well and open excavation concealed section enclosure structure using bored the support form of steel pipe(reinforced concrete)internal support;open section of the enclosure structure using SMW method pile + steel pipe(reinforced concrete)internal support support form;the main structure using reinforced concrete structure.The whole settlement control technology of pipe curtain construction mainly includes five technical contents: selection of pipe jacking machine with settlement control ability,selection of steel pipe to meet the corresponding accuracy requirements,reasonable determination of the jacking sequence,strict control of pipe jacking in and out of the hole parameters and scientific and reasonable control of pipe jacking machine boring parameters and other five technical content.(5)The settlement monitoring of 10 railway lines,7 platforms and columns without columns in Taiyuan station is carried out in the construction of the pipe curtain of the underpass project,and compared with the settlement control value and the standard limit,it is concluded that: steel pipe the maximum value of track settlement completed by jacking is2 mm,and the accumulated value is less than the maximum allowable settlement value of10mm;the accumulated maximum settlement of station platform is less than 10 mm,and the height of station platform meets the standard requirements;there is no encroachment on the canopy column,and there is no tilt,which indicates that underpass construction meets the requirements of building(structure)disturbance,and verifies that underpass project construction overall control settlement technology is scientific and reasonable.