Application Research On Thin-Wall Cylindrical Pile Technology For Strengthening Soft Soil Below Embankment In The Taizhou Railway Station

Cast-in-situ concrete thin-wall cylindrical pile is a major change in piles history, it is a new type pile for strengthening the soft soil below embankment that developed on the basis of immersed tube pile. It makes up for the shortcomings of existing piles Including precast piles,immersed piles,digging hole piles and bored piles,It solved several major problems of the pile better. It It has the advantages of high bearing capacity,adaptable With the changes in geological conditions,low cost.Currently, thin-wall cylindrical pile technology had been applied well in domestic southeastern coastal cities such as Shanghai, Hangzhou, Ningbo and other places. Cast-in-situ concrete thin-wall cylindrical pile is applied to strengthening the soft soil below embankment in railway station for the first time in the Construction of taizhou railway station of yongtanwen PDL. The author has participated in the construction of the pile, to evaluate effects of strengthening the soft soil below embankment, to make in-situ test after laying cover, to research the procedure and analysis effects of thin-wall cylindrical pile strengthening the soft soil below embankment.According to site test and observation, data analysis and the oretical calculation, the paper studies the stressing condition,deformation Characteristic and settlenment rule of thin-wall cylindrical pile and cylindrical pile compound subgrade under of embankmeng load; compares with the computational method which uses frequently at present, the realistic theoretical calculation method for supporting capacity and settlenment of strengthening soft soil by cylindrical pile has been worked out, has provided the theoretical model of design and computation of the cylindrical pile compound subgrade; compares the strengthening effect and economic benefit of thin-wall cylindrical pile,CFGpile,dry jet mixing pile,drill pile,Pre-stressed Steel pipe pile and Cement agitation pile under the same geological and loading conditions. Finally,it is obtained that The quality is stable,The supporting capacity is high,the deformation is small of thin-wall cylindrical pile, it has ability to prevents lateral deformation of the soft soil below embankment effectively. Compares with other piles of strengthening the railway soft soil below embankment, thin-wall cylindrical pile although the expense is high, but technological advance, construction time reduction, geological compatible In view of different soil layer. Technology of thin-wall cylindrical pile is a very efficacious method to solve non-uniform settlenment of railway deep soft soil below embankment, in this aspect it has very big technical superiority and the favorable economic conditions.key words:Thin-wall cylindrical pile, PDL, Strengthening the soft soil below embankment,Test research, Stressing condition, Deformation characteristic, Settlenment rule...