Numerical Analysis Of Force Transfer Between Two Anchoring Interfaces Of Loess Slope Under Earthquake

Loess in China is widely distributed,and is mostly distributed in the western region.In recent years,with the rapid development of the national economy and the needs of national life,more and more important projects need to pass through the loess area.Loess slopes have the characteristics of loose structure,developed joints,and strong collapsibility.It is extremely prone to a series of secondary disasters such as landslides and collapses under the action of earthquakes,which seriously restricts the actual project and the development of the national economy.Rock and soil anchoring has been widely used in slope support because of its unique properties and good results.However,the mechanism of slope anchoring under earthquake is very complicated,which makes the relevant research far behind the engineering reality.Therefore,the anchoring mechanism of loess slope under earthquake Research is very necessary and urgent.In this paper,the loess slope supported by bolts is taken as the research object,and FLAC3D numerical simulation software is used for the first time to study and analyze the shear stress distribution law of the anchoring interface of the bolt-grout and grout-soil of the loess slope under earthquake action.The influence of different influencing factors on the shear stress at the interface between two anchors is discussed.The main conclusions as follows:(1)The analysis of the shear stress at the anchoring interface of the bolt-grout and the grout-soil body found that the shear stress distribution at the anchoring interface under the earthquake is not uniform,both of which are distributed in the form of "large at both ends and small at the middle".At the initial stage of earthquake action,the shear stress at the two anchoring interfaces is small,and is in the elastic stage,and no debonding has occurred;as the seismic load increases,the shear stress at both anchoring interfaces increases,and the grout-soil interface precedes the anchor debonding occurs at the bolt-grout interface.(2)Studying on the distribution of shear stress along the rod length at the two anchoring interfaces under different ground motion parameters(waveform,amplitude,frequency,duration)found that the shear stress at the two anchoring interfaces along the rod length is different for different types of seismic waves.There is no change in the distribution form,only the shear stress value has changed;as the amplitude increases,the shear stress at the two anchoring interfaces and the debonding length of the grout-soil interface gradually increase;as the frequency increases,the two anchoring interface shear stress and the grout-soil interface debonding length increase first and then decrease.With the increase of the duration,the growth rate of the two anchoring interface shear stress increases first and then decreases in each time period.The trend is gradually approaching a stable value.(3)Studying on the distribution of shear stress along the rod length at the two anchoring interfaces under different soil parameters(internal friction angle,cohesion,and gravity)found that with the increase in internal friction angle and cohesion,the two anchoring interfaces shear stress and the debonding length of the grout-soil interface decrease gradually;both increase gradually as the severity increases.Figure[33]table[9]reference[82]...