Study On Mechanical Properties Of The Reinforced Half Grouting Sleeve Connection Under And After High Temperature

With the development of the times,the assembled concrete structure has became more and more important in the housing industrialization system,and it is the important measure of new urbanization development.By contrast,the assembled concrete structure has more advantages than Cast-in-place structure system,on one hand,the components which are used in the assembled concrete structure can be manufactured in factories,which helps to save materials,shorten the construction period,and reduce noise and dust pollution.On the other hand,the prefabricate can realize a facilitate standardization,its production quality is easy to control,It has the advantages of fast return of investment,short construction period,etc.So it is in line with the future direction of housing development.Grouting sleeve is an important form of the assembled concrete structure node connection,and it is also an important way for assembled concrete structure to maintain structural integrity.The study on reinforced half grouting sleeve connection under and after high temperature,firstly,it can verify the reliability of grouting sleeve in fire and after fire so as to improve the design defects of grouting sleeve at high temperature and after high temperature.Secondly,it provides a reference for the study of prefabricated substructures under and after fire so as to avoid the continuous collapse of structures caused by fire.In view of this,in order to investigate that mechanical property of the connecting piece of the half grouting sleeve of the steel bar at high temperature and high temperature,a static tensile tests were carried out on 12 steel bar semi-grouting sleeve of 14 mm connections at high temperature and 39 half grouting sleeve connections of 14 mm at high temperature.At the same time,the bending and compression tests of 27 grouting blocks processed in the same batch were carried out under high temperature and after high temperature.24 steel bars of the same b atch were retained as the control group and the test was carried out under the same conditions as the reference.It is found that in the semi-grouting sleeve connecting specimen,the grouting section of the connecting steel bar will slip relative to the sle eve after high temperature and high temperature,and the steel bar in the grouting section of the specimen will be pulled out after the high temperature loading at 600℃ or the pouring cooling at high temperature.On the basis of this,according to the exis ting bond strength formula,some suggestions are given to avoid the tensile failure of steel bars in the grouting section of the specimen under high temperature and after high temperature.Then,by using of ABAQUS Software,The static tensile test of the h alf grouting sleeve connections at high temperature was simulated.In this article,with sequential coupled thermal stress analysis for the study on the mechanical tensile properties of grouting sleeve at high temperature.First,the heat transfer problem of grouting sleeve at high temperature is analyzed.Then the temperature field of the grouting sleeve is used as the known condition to analyze the thermal stress and obtain the stress-strain field.Finally,the simulation results are in good agreement with th e experimental results.It shows that the test results are accurate and accord with the actual situation.