Numerical Study On The Shear Stress Of Anchored Interface For The Slope With Weak Interlayer Under Earthquake

As one kind of reinforcement technological means for harmful deformation control in engineering,rock and soil anchorage has been widely used in various slope projects.It has became one of the key technologies in many engineering constructions with its own advantages of safety,economy and reliability.To enhance anchoring effects of various slopes,domestic and overseas science researchers have carried out numerous researches on function mechanism of anchoring system under the static loadings,which changes scattered and qualitative knowledge of anchoring mechanism to systematic and quantitative knowledge and lays a solid foundation for research on anchoring system in dynamic action.Our country is one country with frequent earthquakes and widely distributed fault weathering and fracture zone as well as soft ground.It is proved by facts that in this geological environment with poor stability,earthquake is prone to cause side slope collapse,landslip and the other geological disasters.To prevent this kind of geological disaster from causing great threat to life and property safety of human kind,it is required to regard anchoring mechanism of slope anchor rod in dynamic action as research focus in field of rock anchoring technology.In essence,stability of anchoring system is the balance between bearing load and bonding strength of interface and thus bonding strength of interface becomes the most important source of anchoring force and it has crucial influences on operating state of anchor rod components,stability and destruction form of anchoring system.As the most effective mechanics characterization parameter of bonding strength of interface,shearing strength of interface can be used to analyze anchoring mechanism of anchoring interface and therefore the distribution status and change rules of shearing strength for numerous interfaces in anchoring system are one of the most important research contents of anchoring mechanism.Existing researches mainly emphasize on change rules of shearing strength in bolt-grout interface,thus ignoring the role of rod grout-rock interface.In consequence,research on changes of shearing strength of bolt-grout interface and rod grout-rock interface in action of earthquake is one ofeffective approaches to deepen existing theories.(1)Based on a certain theoretical research,this paper proposed one improved interface numerical model and respectively established numerical simulation model of mortar-rock mass interface and rod body-mortar interface by virtue of Flac3 D software.In this model,FISH language is used for prediction of yield failure criterion on two anchoring interfaces,which can reasonably reflect gradual attenuation of interface bonding effects at the reaction place and gradual development of de-bonding destruction.(2)Improved interface numerical model is used for numerical simulation of anchoring rock slope with soft rock strata and for whole process analysis on change and failure law of numerous anchoring shearing strengths.(3)By altering elasticity modulus of anchor rod,mortar thickness and cross section area of rod body,we have discussed influences of anchor rod parameters on shearing strength of bolt-grout interface and rod grout-rock interface and de-bonding rules,then compared and analyzed these two interfaces.(4)By altering anchorage length,array pitch and inclination angle of bolts,we have discussed influences of anchoring method on shearing strength of bolt-grout interface and rod grout-rock interface and de-bonding rules,then carry out in-depth and systematic research on function mechanism of anchoring interface.The research results show how to alter anchor rod parameters and anchoring method to ensure overall stability of slope and anchoring system and thus provide guide for anti-seismic and optimized anchoring design of anchor rod and subsequent large-scale tests on vibrating table.