Bearing Behavior Analysis Of RUHPC And Composite Structural Member

Ultra-High Performance Concrete(UHPC)as a high-performance engineering structural material,with its excellent mechanical properties and durability,is gradually being promoted and applied in high-performance civil engineering infrastructure and building structures at home and abroad.With the continuous expansion of domestic UHPC engineering applications in recent years,the application of UHPC in components such as axial pressure and bias has gradually increased.At present,the performance research of reinforced ultra-high performance concrete(RUHPC)and its high-performance composite components has become an important research direction for new structures and new material structures.Based on the current specifications,this paper comprehensively considers the characteristics of UHPC materials,conducts theoretical analysis on the axial compression,bias,bending performance of RUHPC components and the axial compression performance of RUHPC-NC composite components,establishes its bearing capacity calculation formula,and conducts experimental verification.On this basis,based on ABAQUS finite element software,the influence of different parameters on the bearing performance of RUHPC-NC composite column under axial compression was analyzed.The main research contents are as follows:1.Through a large number of analyses and summarizing the test data of RUHPC axial compression members,the study proposes that the calculation formula of RUHPC member axial compression bearing capacity should be based on the reliability adjustment coefficient of 1.0,and the reliability index should satisfy β greater than or equal to 4.2.The research puts forward a simplified normal section stress graph coefficient suitable for calculation and analysis of the load-bearing capacity of UHPC flexural and flexural-compression members.Theoretical analysis of the force of eccentric and flexural members is carried out,the calculation expression of the bearing capacity is established,and the literature test is obtained.Verification,the influence of the main design parameters on the calculation accuracy of the calculation expression is determined.2.The axial compression bearing capacity of the RUHPC-NC composite column was studied,and the constraint effect of the RUHPC free-dismantling formwork on the core ordinary reinforced concrete and the UHPC material in the stirrups was analyzed and the calculation of the axial compression bearing capacity of the common section form was established.The expression is unified,and compared with the experimental data of the existing literature,the calculation accuracy of the expression is analyzed.3.Through experimental comparison and ABAQUS finite element simulation,the parameter expansion analysis of RUHPC-NC composite column was carried out,and the influence of longitudinal reinforcement and stirrup ratio on the axial compression bearing performance of RUHPC-NC composite column was revealed.The nonlinear finite element modeling method suitable for RUHPC-NC composite columns has laid the foundation for the engineering design of the high-performance composite columns.