Calculations of bending reinforced concrete structures based on a nonlinear deformation model using the LIRA PC
Abstract
Calculations of bending reinforced concrete structures based on a nonlinear deformation model using the LIRA PC
Incoming article date: 17.07.2025The article presents and analyzes the algorithm for calculating bending reinforced concrete structures by normal section based on a nonlinear deformation model recommended in the standards for the design of reinforced concrete structures SP 63.13330.2018. Calculation of reinforced concrete structures based on a nonlinear deformation model is a priority, since it expands the set of controlled parameters, which leads to a more accurate description of the operation of building structures. The features of performing the calculation using this algorithm, as well as other approaches to calculating bending reinforced concrete structures by a normal section based on deformation and other models, are considered. The sequence of calculations using computer technologies is shown using the example of calculations in the engineering nonlinearity1 system of the LIRA-SAPR software package. The results of calculating a rod element of the calculation scheme are given: changes of the bending moment, stiffness, and deformation modulus for finite elements along the rod length. In this case, the calculation in the engineering nonlinearity1 system is performed with subsequent adjustment of the stiffness characteristics of the finite elements, carried out during the iterative calculation, with clarification of the stress-strain state, deflection of the element and its reinforcement. Additional capabilities of performing calculations using the engineering nonlinearity2 system are described: expanded the possibilities of assigning various laws of material deformation, describing the loading of the calculation scheme, reinforcement of structures, and the possibility of using a step processor.
Keywords: bending reinforced concrete structures, nonlinear deformation model, calculation scheme, calculation algorithm, PC LIRA-SAPR, engineering nonlinearity, system