Numerical Simulation Of Pressure-dispersion Anchor Cable Under Seismic

In recent years,with the frequent occurrence of earthquake,the research on prestressed anchor technology under the seismic action became necessary.Wherein the pressure-dispersion anchor cable technology has been widely used in practical application because of its special structure and reasonable mechanical characteristics,but its theoretical research was relatively slow.The thesis combines the national natural science funds“The reinforced mechanism and design method of slope reinforced by pressure-dispersion anchor cable”.The axial force of anchor amplification effect in reinforcement slope under different seismic waves of different slope elevation has been research in the paper by theoretical analysis and numerical simulation.At the same time,on the basis of the research,the mechanical characteristics of the pressure-dispersion anchor cable under static and dynamic situations has been studied.The main work and achievements are as follows:?1?Based on the summary of anchoring mechanism of pressure-dispersion anchor cable and research progress of slope anchoring system dynamic response under earthquake,the current slope reinforcement problems in design has been noted,and the main contents of this paper has been put forward.?2?Based on typical anchor reinforcement slope model,numerical simulation methods FLAC^3D had been used in anchored rock slope under three different seismic waves and seismic waves of different magnitude to simulate anchor force,we analyzed the different elevation slope anchor the force.The results showed that:anchored slope under different seismic waves have different peak maximum axial force,EI wave minimum,Concrete wave followed,KOBE wave maximum;three different height slope under earthquake,the maximum anchor force value is both appear at its base;at 9 earthquake,five-grade slope axial force peak decreases with slope elevation increase.In six and seven grade slope the maximum axial force peaks at its base,on the waist and top of the slope axial force peaks are also large,the slope at its base,and the top of the hill slope waist anchor the rear axle shock force peaks when compared with the static forces were 5.7%,3.9%,3.9%,that is anchor at the top of the hill slope height increase after the axial force increases more obvious effects.?3?On the basis of seismic response history analysis of axial force on the pressure dispersed anchor in the dynamic action carried out,numerical simulations to study the size of the interfacial shear stress grouting and anchoring section and the axial stress distribution,the results showed that:when the dynamic action of the earthquake,the anchoring segment relatively static force has significantly increased its axial stress grout and interfacial shear stress were significantly increased.The maximum axial stress grout relatively static magnified about 1.55 times,interfacial shear stress enlarged 1.38 times,anchoring segment discontinuity increases only along the longitudinal direction of the grouting distribution significantly longer,which is about1.3m.Length distribution compared to static force?about 0.8m?increased significantly?4?Based on a comprehensive analysis of simulation results,considering slope seismic effects on anchor design,some suggestions was given:anchorage force during slope seismic design,consider the anchor axial force at different locations in different slope magnifying seismic influence,coefficient slope at different heights in different parts of the anchorage force calculation of different values,in large seismic intensity,according to the top of the hill slope height appropriate increase in the size of the anchorage force;considering pressure dispersed anchor anchored length under earthquake n,it may be appropriate to increase the anchorage section length.