Research On Embedded Depth Of Soldier Pile Wall On Rock And Soil Excavations In Dalian

Foundation pit engineering is an important branch in geotechnical engineering,more and more city of deep excavation engineering, more and more deep， thetransformation of the old city project is limited to the trunk road, thesurrounding city surrounding network etc. the pit surrounding space is limited,foundation pit support requirements, more and more high, The conservative design ofthe foundation pit engineering will cause the engineering economy, the safety reservewill cause the foundation pit hidden trouble, therefore, how to guarantee thefoundation pit design economic and reasonable is a difficult problem in geotechnicalengineering.For the more important level of excavation, the case of soldier pile retainingm o r e c o m m o n, t h e a b i l i t y o f s u p p o r t i n g p i l e h a s g o o d d e f o r m a t i o ncontrol, safety degree is high, wide applicability stratum, supporting pile embeddeddepth for soil foundation pit is calculation methods more clearly, for soil rockcomposite foundation calculation theory is not mature for mainly in the area,experience based, supplemented by calculation. Soil and rock strata combinationrow pile foundation embedded depth design can refer to specification structuredepth design, safety will be the foundation pit is greatly improved, but in weatheredrock embedded depth is too large, the construction is difficult.Papers by analysis and calculation of the Dalian area of two typical combinationof soil and rock pit row pile design case, the following conclusions:（1）Embedded depth of strongly weathered rock, point the number of channels asingle fulcrum for the supporting structure, the calculation of the process canbe highly weathered slate according to soil treatment, in the embedded depth meetsthe stability requirements, combined with regional experience, the embedded depth ofcomparable structure depth specifications appropriate to reduce. （2）Embedded depth of the pile anchor retaining structure in weathered rocks,calculated, supporting structure embedded depth to meet stability requirements to adepth of1m depth, the actual design of embedded depth of weathered rock take1.7~2m, half pit depth of0.1to0.15times for the specification of structural depth, fromsupporting effect, the depth is economically reasonable.（3）Embedded depth of the weathered rock multi-pivot support structurehanging feet, unable to be embedded directly supporting piles bottom pit, onlyweathered rock embedded depth0.5m, in order to ensure the lower part of thesupporting piles and weathered slate stability, supporting the use of rock boltsanchoring piles reserved rock shoulder plus prestressed cable, computing process willbe reserved for the lower segment embedded solid rock pile at the bottom of theshoulder plus supporting bolt pullout seen as supporting piles were calculated afterconstruction pit stability, to achieve the desired effect, indicating that the method isfeasible.（4）External surface and the slope inclination structure is unfavorablecombination of free surface slope forward for analysis, the safety factor is calculatedalong the fold line sliding surface is to meet stability requirements.