Research On Eccentric Compression Performance Of Existing RC Column Reinforced With High Strength Grouting Material

Because of its advantages of simple construction,low cost and obvious improvement of bearing capacity,the method of increasing section reinforcement has always been the most widely used reinforcement method in reinforcement engineering,but it is often difficult to vibrate because of the special structure in practical construction operation,so it is easy to form holes to affect the reinforcement effect.The cement-based high-strength grouting material,as a kind of excellent reinforcement material,has the characteristics of self-leveling,micro-expansion,fast hardening,high strength,and non-polluting,which is especially suitable for strengthening special structures with harsh construction conditions.At present,the preparation method of the grouting material and the influence of each component on the performance have been fully studied,and it is widely used in the rapid reinforcement and maintenance of special structures,but the experimental research and related reports on the reinforcement of eccentric compression columns with grouting material Less,the excellent mechanical properties of cement-based high-strength grouting material have not been fully utilized,which limits the development of my country’s reinforcement industry,so the following research is carried out:(1)Using cement-based high-strength grout material to strengthen 10 columns with the same initial conditions and eccentric pressure test,this paper mainly analyzes the change law of eccentric pressure column destruction form,limit carrying force and force state under the influence of different eccentric distance,reinforcement thickness and reinforcement form,and verifies the reinforcement effect of high-strength grout reinforcement eccentric pressure column and its practicality in the field of structural reinforcement.The test results show that the use of cement-based high-strength grouting to increase the cross-section method of reinforcement significantly improves the stiffness and ultimate bearing capacity of the eccentric compression column.The reinforcement thickness mainly affects the overall stiffness and stress state of the eccentric compression column,and the use of unilateral In the form of reinforcement,the reinforcement effect is similar to that of changing the eccentricity,and the excellent compressive performance of the high-strength grouting material is brought into play.The form of reinforcement mainly affects the confinement capacity of the original column core concrete and the strength utilization rate of concrete materials,and the best reinforcement effect is obtained when the form of reinforcement on both sides is adopted,and the ultimate bearing capacity is increased by 249% to 329%.(2)The finite element simulation of the test process is carried out through MIDAS/FEA software,and the ultimate bearing capacity,stress and strain cloud diagrams and crack distribution of the eccentric compression column are obtained,which are compared with the actual test results to verify the effectiveness of this simulation and test.(3)The test results and simulation results are summarized,the influence of increasing the thickness of reinforcement and changing the form of reinforcement on the bearing capacity and stress state is analyzed,and the reinforcement scheme that is most suitable for the practical application and promotion of the reinforcement project is selected.