Abstract
In recent years, the material behavior dependence of laboratory concrete specimens built with the same concrete mixture under the same load conditions to their geometrical sizes is well established. This phenomenon which is observed not only in concrete but also in most quasi-brittle materials such as rock, ceramic or composite materials is now called as size effect. Many of the existing structural analyzing codes are not able to consider this important feature of concrete structures especially under compressive loadings. However we know that the main purpose of concrete application in structural members is to resist compression. The aim of this study is to show the ability of author's recently developed 3D finite elements code equipped with the proposed author's newly micro-planes damage based model for considering of compressive size effect of plane concrete. To do so, two different sizes of cubic concrete specimens are modeled with mentioned code under the uniaxial compressive test and their fracture mechanisms, pre-peak and post-peak strain-stress paths are investigated. Obtained results reveal the good coincidence with experimental evidences. In fact, the combination of proposed micro-planes damage based model and developed presented 3D finite elements technique creates a powerful numerical tool to capture and predict precisely strain localization and fracture mechanism in the specimens and consequently to assess properly the compressive size effect of plane concrete in analysis and design.
Highlights
It is a well-known fact that there is an effect of size differences in behavior of specimens made with quasibrittle materials such as concrete, rock, ice, ceramic and composite materials under loads [1, 2 and 3]
This phenomenon which is observed mostly in quasi-brittle materials is called as strain localization. The size of this fracture process zone and the amount of fracture energy release are dependent on geometrical size of the specimen
To investigate the capability of presented numerical model [6] in this domain, two different sizes of cubic concrete specimens are modeled with mentioned code under the uniaxial compressive test and their fracture mechanisms, pre-peak and postpeak strain-stress paths are investigated
Summary
It is a well-known fact that there is an effect of size differences in behavior of specimens made with quasibrittle materials such as concrete, rock, ice, ceramic and composite materials under loads [1, 2 and 3]. The difference is a direct consequence of energy release into a finite-size fracture process zone (damage localized zone). This phenomenon which is observed mostly in quasi-brittle materials is called as strain localization. The size of this fracture process zone and the amount of fracture energy release are dependent on geometrical size of the specimen. Most analyzing codes for concrete structures do not consider the effect of size in analysis. Some concrete structural members such as central plan position columns in concrete frame buildings experience compressive loading condition
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have