Abstract
This paper presents the influence of silica sand, local crushed sand and different supplementary cementing materials (SCMs) to Portland cement (C) ratio (SCM/C) on the flexural fatigue performance of engineered cementitious composites (ECCs). ECC is a micromechanically-based designed high-performance polymer fiber reinforced concrete with high ductility which exhibits strain-hardening and micro-cracking behavior in tension and flexure. The relative high cost remains an obstacle for wider commercial use of ECC. The replacement of cement by SCMs, and the use of local sand aggregates can lower cost and enhance greenness of the ECC. The main variables of this study were: type and size of aggregates (local crushed or standard silica sand), type of SCMs (fly ash “FA” or slag), SCM/cement ratio of 1.2 or 2.2, three fatigue stress levels and number of fatigue cycles up to 1 million. The study showed that ECC mixtures produced with crushed sand (with high volume of fly ash and slag) exhibited strain hardening behavior (under static loading) with deformation capacities comparable with those made with silica sand. Class F-fly ash combined with crushed sand was the best choice (compared to class CI fly ash and slag) in order to enhance the ECC ductility with slag–ECC mixtures producing lowest deflection capacity. FA–ECC mixtures with silica sand developed more damage under fatigue loading due to higher deflection evolution than FA–ECC mixtures with crushed sand.
Highlights
Normal cementitious materials have proven to be a suitable material in infrastructure constructions and have been successfully implemented in numerous projects around the world.the deteriorating condition of the infrastructure in North America and elsewhere due to inherently brittle failure resulting from tensile and impact loading in such cementitious materials has motivated authorities and researchers to seek new technology for enhancement of concrete material properties
This paper describes the results of an experimental investigation studying the effects of silica sand, local crushed sand and different supplementary cementing materials (SCMs)/C ratio on the flexural properties and fatigue performance as well as crack development characteristics of engineered cementitious composites (ECCs) mixtures
This paper describes the performance engineered cementitious composites (ECCs) under static and fatigue loading conditions
Summary
Normal cementitious materials have proven to be a suitable material in infrastructure constructions and have been successfully implemented in numerous projects around the world. The type, size and amount of fiber, matrix ingredients and interface characteristics are tailored for multiple cracking and controlled crack width in ECCs. Aggregates typically occupy an important volume fraction in conventional concrete, and have important effects on different aspects of material properties. Un-hydrated FA particles with small particle size and smooth spherical shape serve as filler particles resulting in higher compactness of the fiber/matrix interface transition zone that leads to a higher frictional bonding This aids in reducing the steady-state crack width beneficial for long-term durability of the structure [18,19,21,22]. This paper describes the results of an experimental investigation studying the effects of silica sand (as a control material), local crushed sand and different SCM/C ratio on the flexural properties and fatigue performance as well as crack development characteristics of ECC mixtures. The recommendations of this paper will be beneficial to engineers, designers and local industries engaged in manufacturing and using cost-effective and greener ECC mixtures for construction applications
Sign-in/Register to view highlights & summary 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.
