Vibration Response Due To Dynamic Compaction On The Platform Of Ladder-type Soil Slope And Its Prevention

Theadvantages of the dynamic compaction method included the simple construction,obvious effect,and low cost.And it was proved that dynamic compaction method was a better foundation treatment technology than others.Anddynamic compaction method was widely applied to the foundation treatment technology in practice.The vibration of the foundation soil and the surrounding environment caused by dynamic compaction might induce vibration destroy,which limited its application in the slope foundation treatment project.Therefore,it was of certain engineering value to research the slope vibration response induced by the dynamic compaction and to explore the preventative measures of damage caused by the method on the slope platform.In this paper,the numerical calculation method was used to study the vibration response of dynamic compaction and its prevention for the Ladder-type slope platform,and the regularity of the vibration response induced by the dynamic compaction of the slope was revealed.The specific research works and achievementsof this paper were listed in detail as follows:(1)A simulation method of vibration caused by dynamic compactionwas put forward based on the ABAQUS finite element software.By comparing with the test of referenced papers,the rationality of simulation methodfor the vibration caused by dynamic compaction was studied,which included “the hammer impact method” and “the simplified load method”.Vibration response on the slope variation caused by dynamic compaction was analyzed.“The hammer impact method” wasa better method than “the simplified load method”.(2)The attenuation regularity of themaximum and minimum of vibration acceleration,velocity,and displacement caused by the dynamic compaction in vertical direction,radial direction and surface of the one level platforms of ladder-type slope was analyzed.And it revealed that the regularity of the peak value of thevibration component responsecaused by the dynamic compaction on slope platform was influenced by the shapes of the slope(the angle of the first and second grade slope and platform height),the slope soil constitutive model parameters(the Elastic Modulus E,Poisson's Ratio v,Cohesion c,and internal friction angle ?)and the parameters of dynamic compaction(the ram energy e and hammer radius R).(3)Slope vibration response induced by dynamic compaction on the one level platform of ladder-type slope was obtained during taking some preventative measures for vibration,likes the opentrench isolations with different geometric shape and vibration trench isolations with different filling materials.By setting the open trench isolations with different longitudinal length at the edge of the platform near to the secondary side slope foot and setting the open trench isolations with different depth on both sides of the platform,the variation regularity of different geometry of the open trench isolationswas obtained during the progress of dynamic compaction.By setting the open trench isolations with the depth of two meters in the both sides of platform,isolating effect of vibration of the open trench isolationswas researched.By setting the filling trench isolations with different filling materials,likes sandy gravel,aerated concrete and light aggregate concrete,the regularity of peak value on the slope platform during the progress of dynamic compaction was obtained.(4)The vibration response of project example about the dynamic compaction on platform was analyzed,and the preventative measures was suggested.Taking 16-16 section of slope foundation in the cover layer of the Jinfoshan hydro-junction project in Nanchuan district of Chongqing as an example,the peak attenuation regularity of vibration acceleration,velocity and displacement component caused by the dynamic compaction was analyzed under the condition of taking none measures,taking the filling trench isolations of filled ditches with lightweight aggregate concrete,and the open trench isolations.The stability of slope in the process of dynamic compaction has been studied.And the control criterion of corresponding vibrationand the preventative measure for dynamic compaction were proposed.