Study On Application Of The Large Diameter Anti Slidepile Group In A Slope Along The Railway From Jilin To Hunchun

For nearly twenty years, with the flourishing development of the domestic economy, the railway mileage has increased year by year, and the construction process has brought many problems, especially in the slope governance, especially the research on motion mechanism of the slope excavation process and measures of prevention and treatment. Today, the artificial dig hole pile with anchor cable construction of the slope supporting measures, or groups of micro pile layout. The former belongs to the large section of anti slide pile, bending and shear ability is prominent, but easily disturbed rock (soil) body caused by structural damage, reduce the quality and safety of construction, construction conditions have also been restricted; and although with micro pile of rock (soil), small disturbance is not limited, the construction speed and construction conditions quick, but often not suitable for control of large scale landslide. In view of this, in the new Ji Tu Hui railway passenger line in Yanji K283 expansive soil slope treatment project, proposed to cap connection type large diameter pile group governance measures, the comprehensive consideration of the rectangular section of single pile bending performance and bored pile construction machinery etc.This paper will start from the theoretical analysis, analysis of monitoring data, combined with the numerical simulation research of large diameter pile cap connection type combined anti slide pile group mechanism of slope reinforcement, get some meaningful conclusions, for future in-depth study on the structure of this kind of support material. The main contents are as follows:(1) review of previous studies, mainly on the domestic and foreign anti slide pile retaining structure, expansive soil landslide, landslide monitoring and numerical simulation, the four aspects of the status quo summarized;(2) combined with the Yanji K283 segment slope geological survey, analysis of the expansive soil slope deformation and instability mechanism, that caused the slope cutting excavation unloading stress leads to decrease of soil strength is redistribution and abundant rainfall, resulting in the occurrence of landslide causes;(3) according to the slope characteristics, take the cap and pile group combination structure, the anti sliding mechanism mainly in three aspects:the effect of bending, shear and pile-soil composite effect, and the single, double-"II" anti slide pile internal force gauge group numerical results show that, when the pile group structure, the evolution from single pile arrangement of "2x2" type structure "3x3" type of anti slide structure of large diameter combined, the internal force of the structure has been greatly improved, the structure more reasonable;(4) soil slope and combined anti slide pile group conducted on-site monitoring for Yanji K283 expansion, from the slope surface and deep displacement data, the displacement of the frequent fluctuations, large displacement, with the construction of gradually stabilized, determine the 10m position for the landslide slip surface, consistent with the geological prospecting data; from the pile group data, because the cap, almost the same in the displacement of pile top, and reaches the maximum, the data table row pile internal force was about 1.5 times of back pile;(5) select the monitoring section of the â…¡ section, the Moore-Kulun criteria, to determine the parameters of the model, simulated the actual slope and pile structure using ABAQUS finite difference software. The simulation results show that:in the landslide thrust, the overall structure of the single pile along the pile displacement of the same trend, a considerable amount of displacement, stress is similar, consistent with the monitoring data, indicating better limits, cap before the rear pile deformation.