Study On High Temperature Mechanical Properties Of Reinforced Sleeve Grouting Connection

In prefabricated building structures,the reinforcement sleeve grouting technique is usually used to connect the prefabricated components together to form a whole.Therefore,the reinforced sleeve grouting connection members play an irreplaceable role in prefabricated buildings.Supported by Liaoning Provincial Natural Science Foundation Project(2015020600),this paper studies the high-temperature mechanical properties of reinforced sleeve grouting joints in prefabricated building structures under fire conditions.The main research contents are described below.At first,this paper USES the finite element software ABAQUS to establish the connection of different diameter steel(D16,D20 and D25)steel sleeve grouting connection component numerical model,and based on the sequential coupling analysis on the high temperature thermal coupling analysis,i.e.,the first way based on uniform heating temperature field analysis of steel sleeve grouting connecting component,then imported into the mechanical model of temperature field,and the connection under axial tensile load performance for numerical simulation analysis.Then,the influence of steel diameter(D16,D20,D25)and heating temperature(20 ° C,100 ° C,200 ° C,300 ° C,400 ° C,500 ° C,600 ° C,700 ° C,800 ° C)on the Mises stress distribution and strain distribution of steel sleeve grouting connectors was investigated.Finally,for the sake of fabricated structure numerical model is set up in more efficient in the future,this article will steel sleeve grouting connection equivalent components as part of a whole,and based on the numerical simulation data,this paper puts forward the equivalent integral parts under the condition of different temperatures of equivalent stress-strain curve and equivalent double broken line stress-strain curve and equivalent elastic modulus,and discusses the equivalent integral components of yield stress,the equivalent yield strain,the equivalent elastic modulus changing with the heating temperature.The results show that under the axial tensile load,the maximum Mises stress of the reinforced bush grouting connection decreases with the increase of heating temperature.When the heating temperature is below 300?,the maximum Mises stress of the reinforced bush grouting connection decreases significantly.With the increase of temperature,the maximum Mises stress of steel bush grouting coupling was significantly decreased with the increase of temperature of 300?.In addition,for the equivalent model of the reinforcement sleeve grouting connection members,the reinforcement sleeve grouting connection members with different diameters have different equivalent elastic modulus and equivalent yield stress,and all of them decrease with the increase of temperature.For the steel bar sleeve grouting connection member connecting D16 and D25 steel bars,the equivalent yield strain increases with the increase of temperature and reaches the peak value at 500?.When the temperature exceeds 500?,the equivalent yield strain and the equivalent yield stress gradually decrease.For the steel bar sleeve grouting connection member connected with D20 steel bar,the equivalent yield strain increases with the increase of temperature and reaches its peak value at 400?.When the temperature exceeds 400?,the equivalent yield strain and the equivalent yield stress gradually decrease.