Study On Mechanical Properties Of Newly Forging Grouting Sleeve Connection

With the continuous progress of China’s construction industry,the fabricated building structure,which has become a new research direction,is also developing rapidly,and its relevant theoretical research and engineering practical application have made breakthrough progress.In the building with prefabricated structure,the main stress part of its internal structure is the vertical prefabricated component,and the connection between components is very easy to get failed.Therefore,whether the connection node between each component is reliable has a key impact on the overall performance of the prefabricated building structure.In the application of member joint connection in fabricated structure,the most widely used method is reinforcement sleeve grouting connection technology.This paper summarizes the existing research on sleeve grouting connection technology by scholars at home and abroad,designs a new forging grouting sleeve connection specimen,and analyzes the influence of reinforcement diameter,eccentricity and other factors on the performance of the specimen under different stress conditions.The main research contents and results are as follows:(1)A total of 36 joint specimens of semi grouted sleeve specimens and full grouted sleeve specimens with three reinforcement diameters(16mm,20 mm and 25mm)were designed and manufactured,which were subjected to tensile tests.The effects of anchorage lengths and reinforcement eccentricity on the properties of specimens were studied.The results show that the three anchorage lengths have no significant effect on the ultimate bearing capacity of the two grouting sleeve specimens,but the strengthening stage of the half sleeve specimen is the longest when the anchorage length is 8.5 times the diameter of the reinforcement;Whether the reinforcement is eccentric or not has little effect on the ultimate bearing capacity of the two sleeve connection specimens.In addition,the anchorage length has the greatest influence on the axial strain of the semi grouted sleeve specimen.When the anchorage length is 8 times the reinforcement diameter,the axial strain changes fastest with the load.(2)A total of 48 joint specimens of half sleeve specimens and full sleeve specimens with three reinforcement diameters were designed and manufactured.The cyclic tests were carried out on them,and the effects of the maximum cyclic force and the number of cycles on the properties of the specimens were studied.The results show that the stiffness of the high stress cyclic specimen will increase compared with the unidirectional tensile specimen.When the cyclic force reaches 460 Mpa,the ultimate bearing capacity of the specimen is the largest,but its peak displacement is significantly lower than that of the unidirectional tensile specimen;The slope of the curve in the elastic stage of large deformation cyclic specimen will increase with the increase of the number of cycles,while the slope of the curve in the elastic stage of unidirectional tensile specimen is small.(3)In ANSYS finite element software,B20 sleeve specimen is selected for modeling and calculation.The simulation failure form of specimen is basically consistent with the test result,which is broken by reinforcement failure.The maximum stress and maximum plastic strain of the simulated specimen appear on the reinforcement,and the stress and strain on the sleeve surface are small,indicating the sleeve’s sufficient bearing capacity and large deformation space.Figure 34 Table 12 References 76...