Study On Seismic Technology Of Anti-slide Pile With Anchor-cable Based On Centrifuge Shaking Table Model Test

Anti slide pile with anchor cable is an effective method to reinforce large or super large slope or landslide.In spite of this,the static design method has not been able to reflect the real force characteristics of anti slide piles,which has not been recognized by the academic and engineering circles.The damage investigation of Wenchuan earthquake showed that the anti slide pile with anchor cable was still intact when the actual intensity exceeded the fortification intensity.This indicated that the design of the safety margin was too high,although it was safe,but not economical,which did not conform to the idea of green development in China.The seismic technology of Anti slide pile with anchor cable included seismic response,strengthening mechanism,failure mode,seismic design methods and measures.Untle now,there was no relevant provisions about above concents in the specification.The existing results can not reflect the true connotation of seismic technology,and the seismic performance comparison of pile and anti slide pile with anchor cable was still lack.To this end,this paper summarized the relevant research progress internal and external,and pointed out several key problems needed to be solved.The most common accumulation landslide actual engineering,reinforced by anti slide pile with anchor cable,was chosen as the reference prototype,and 3 groups of dynamic modeling tests were complished using the international advanced,can realize a prototype simulation of the centrifugal shaking table model test platform under 50 g centrifugal acceleration condition.Using these modeling tests,the the characteristics and laws of seismic response of anti slide pile with ancor cable,pile and their comparison was researched.The innovative work showed as follows:1.A new mechanism for the dynamic model test of anti slide pile with anchor-cable was developed.The prestressed anchor cable axial force micro testing mechanism was researched independently,which can be used in the anti slide pile with anchor cable dynamic centrifugal modeling test.For the first time,the real-time measurement of anchor axial force in the anti slide pile with anchor cable system was realized under super gravity field condition,which provides a new technicique for the prestressed anchor cable model tests.2.The seismic response processes and laws of anti slide pile with anchor-cable were revealed.The Settlement deformation and PGA amplification effect of landslide,earth pressure and dynamic bending moment of pile,and the response characteristics and regularity of anchor axial force were revealed and compared between the single pile and group pile during different earthquake inputs.The results made up the blank of field monitoring data in actual earthquakes.3.The problem existing in the design specification of anti slide pile was pointed out.The lows that the thickness of sliding body only changed the value of landslide thrust of anti slide pile without changing the distribution form and the maximum dynamic pressure point and bending moment point moved down in the earthquake were found.These laws were different from the rule of pseudo static method which assumed that the maximum point did not change during earthquakes.4.The guiding opinions and evidences for pile type selecting in Engineering were proposed.The mechanism of reducing the slope damage degree and the displacements was that the anti slide pile with anchor-cable changed the distribution of dynamic earth pressures and dynamic bending moments and the slope failure mode.Based on the above,the anti slide pile with anchor-cable was a optimal method for protecting buildings on the slope crest and avoiding secondary disaster after earthquakes.The academic value of this article lies in: through the dynamic centrifuge model prototype simulation,the rules of seismic response of anti slide pile with anchor cable and anti slide pile were systematically revealed,and seismic performance comparison of different kind of pile were researched.The research results can provide valuable information and experience for the improvement of existing design specification and establishment and development of scientific and reasonable seismic design theory and method.