Determination of elastic characteristics of cement stone to predict the fatigue life of concrete
Journal: Вестник МГСУ / Vestnik MGSU (Vol.17, No. 04)Publication Date: 2022-04-30
Authors : Kurbatov Yuri E.; Kashevarova Galina G.;
Page : 476-486
Keywords : fatigue failure; damage accumulation models; linear summation hypothesis; structural simulation modeling; strength limit of cement stone; modulus of elasticity; Poisson’s ratio;
Abstract
Introduction. The problem of fatigue failure of concrete is one of the least studied in computational practice. The lack of reliable data on the actual processes of accumulation of fatigue damage occurring in the structure of this material during cyclic exposure does not allow us to form a methodology for calculating concrete structures that perceive such loads. To develop the above methodology, it is proposed to use structural simulation modeling. For this purpose, mathematical models of concrete damage under the influence of cyclic loading are considered. The purpose of the study is to determine the elastic and strength characteristics of cement stone for further development of a methodology for predicting the fatigue life of concrete, taking into account the nonlinear kinetics of damage accumulation. Materials and methods. The strength limits of cement stone during bending and compression were determined by conducting a full-scale experiment on a testing machine and a hydraulic press. Elastic characteristics of cement stone were obtained as a result of static tests of cement stone samples of various shapes on the universal electromechanical system with the joint use of the digital optical system for analysis of deformation and displacement fields and the acoustic emission signal recording system. Results. During the tests of cement samples for bending and compression, the values of the corresponding bending and compression strength limits were obtained, which made it possible to confirm the design strength class of cement 32.5 N. Inhomogeneous fields of longitudinal and transverse deformations were obtained using a digital optical system to further determine the basic elastic characteristics of the material. Obtaining acoustic emission signals during the experiment made it possible to reflect the dependences of various acoustic emission parameters on time. Conclusions. The first stage of the proposed methodology for predicting the fatigue life of concrete is performed, taking into account the nonlinear kinetics of damage accumulation, as a result of which the modulus of elasticity and the Poisson’s ratio for cement stone are determined. The obtained data can be used to create a numerical model of the concrete structure, and the use of acoustic emission signals allows us to estimate the kinetics of damage accumulation in the material.
Other Latest Articles
- Algorithm for developing a computational model of a wooden multi-storey building
- Application of the G.A. Geniev, N.S. Chausova method for stability of shallow shells investigation
- Settlement and bearing capacity of foundations adjacent to vertical excavation
- Urban bio-social infrastructure as a patronized goods: institutional environment and structural changes
- Urban zoning features of territories for tourist services facilities placement in coastal cities
Last modified: 2022-06-08 04:41:00