Abstract
Achievements are presented for truss models of RC structures developed in previous years: 1. Two constitutive models, biaxial and triaxial, are based on regular trusses, with bars obeying nonlinear uniaxial σ-e laws of material under simulation; both models have been compared with test results and show a dependence of Poisson ratio on curvature of σ-e law. 2. A truss finite element has been used in the nonlinear static and dynamic analysis of plane RC frames; it has been compared with test results and describes, in a simple way, the formation of plastic hinges. 3. Thanks to the very simple geometry of a truss, the equilibrium equations can be easily written and the stiffness matrix can be easily updated, both with respect to the deformed truss, within each step of a static incremental loading or within each time step of a dynamic analysis, so that to take into account geometric nonlinearities. So the confinement of a RC column is interpreted as a structural stability effect of concrete. And a significant role of the transverse reinforcement is revealed, that of preventing, by its close spacing and sufficient amount, the buckling of inner longitudinal concrete struts, which would lead to a global instability of the RC column. 4. The proposed truss model is statically indeterminate, so it exhibits some features, which are not met by the “strut-and-tie” model.
Highlights
In 1967, in a pioneering work [1], D
A significant role of the transverse reinforcement is revealed, that of preventing, by its close spacing and sufficient amount, the buckling of inner longitudinal concrete struts, which would lead to a global instability of the RC column; 4) The proposed truss model is statically indeterminate, so it exhibits some features, which are not met by the “strut-and-tie” model
In his “theorie des equivalences” stated that simple truss finite elements give equivalent results with the usual more complicated continuum finite elements. This idea was extended to problems with material nonlinearities and to the nonlinear static and dynamic analysis of plane RC frames by P
Summary
In 1967, in a pioneering work [1], D. In order to describe the nonlinear biaxial or triaxial stress-strain behavior of a structure by the Finite Element Method, constitutive models for the structural materials have to be developed in order to be embodied in the individual finite elements. In his “theorie des equivalences” stated that simple truss finite elements give equivalent results with the usual more complicated continuum finite elements This idea was extended to problems with material nonlinearities and to the nonlinear static and dynamic analysis of plane RC frames by P. As the bars of the proposed finite element include the main material nonlinearities of concrete and steel, that is concrete tensile cracking and ultimate compressive strength, as well as tensile yield of reinforcement, the proposed truss model can, in a simple way, describes the formation of plastic hinges in a RC frame. Some of the achievements of the above proposed truss models for nonlinear analysis of structures, mainly RC structures, proposed in previous years, will be described in more detail
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
