Fracture Behavior Test And Numerical Simulation Analysis Of Polymer Grouting Materials

Non-aqueous reactive polymer grouting material has excellent characteristics such as early strength,high strength and good impermeability,and is widely used in the trenchless repair of infrastructure such as highways,pipelines,tunnels and dams,and has received extensive attention.In practical engineering applications,polymer grouting materials are affected by factors such as external temperature changes,acid-base-salt environment corrosion,insufficient reaction of material components and external loads,etc.,damage cracks may occur on the surface or inside of the material,and gradually It develops into macroscopic cracks,which affects the mechanical properties and service effect of polymer grouting materials.There are few studies on the influence of the existence and development of cracks on the properties of polymer materials.Therefore,it is necessary to study the fracture properties of polymer grouting materials.Based on this,this paper uses a combination of experiments and numerical simulations to study the fracture properties of polymer grouting materials.The main research contents and achievements are as follows:（1）The tensile fracture properties of polymer grouting materials with different densities were studied by uniaxial tensile test,the tensile fracture failure patterns of the materials were observed,and the stress-strain curve was drawn.satisfy a linear relationship.（2）The static three-point bending test of the polymer grouting material with cracks was carried out,and the plane fracture toughness K_Qand surface fracture energy G_ICof the polymer material were analyzed and obtained with the increase of the material density;the same density condition The fracture toughness value K_Qof the polymer grouting material is not significantly affected by the ratio of the joint height,which is an inherent property of the material.Based on acoustic emission technology（AE）,the crack propagation of the material is monitored,and the characteristic parameters such as AE ringing count,energy and amplitude are used to characterize the crack propagation and material damage of the polymer grouting material,and the material crack is obtained by analysis.Damage evolution equation during expansion.（3）Using the finite element analysis software ABAQUS and the extended finite element method（XFEM）,the fracture numerical model of the homogeneous polymer grouting material with cracks was established,and the polymer grouting with different densities and different fracture height ratios was obtained through analysis.The crack propagation process of the material,as well as the changing laws of parameters such as PHILSM,STATUSXFEM,and stress,and the simulation results are in good agreement with the experimental results.（4）Considering the influence of different density distribution inside the polymer grouting material,the fracture process of the crystalline polymer grouting material was studied and analyzed.Influence law of fracture properties of grouting materials;combined with XFEM to simulate the crack propagation process of grouting materials containing crystalline polymer,firstly compare and verify with the test results,and secondly analyze and predict the crack propagation law of grouting materials containing crystalline polymer.