Abstract
Geopolymers are a promising class of inorganic materials typically obtained from an alluminosilicate source and an alkaline solution, and characterized by an amorphous 3-D framework structure. These materials are particularly attractive for the construction industry due to mechanical and environmental advantages they exhibit compared to conventional systems. Indeed, geopolymer-based concretes represent a challenge for the large scale uses of such a binder material and many research studies currently focus on this topic. However, the behaviour of geopolymers under high dynamic loads is rarely investigated, even though it is of a fundamental concern for the integrity/vulnerability assessment under extreme dynamic events. The present study aims to investigate the effect of high dynamic loading conditions on the tensile behaviour of different geopolymer formulations. The dynamic tests were performed under different strain rates by using a Hydro-pneumatic machine and a modified Hopkinson bar at the DynaMat laboratory of the University of Applied Sciences of Southern Switzerland. The results are processed in terms of stress-strain relationships and strength dynamic increase factor at different strain-rate levels. The dynamic increase factor was also compared with CEB recommendations. The experimental outcomes can be used to assess the constitutive laws of geopolymers under dynamic load conditions and implemented into analytical models.
Highlights
Geopolymers, known as “alkali-activated cements” or “alkali-activated aluminosilicates”, represent a new class of high performance inorganic materials characterized by a three dimensional, CaO-free, silico-aluminate chemical structure [1]
They can be produced by mixing reactive aluminosilicate materials such as metakaolin [2, 3], industrial [4] or natural waste products [5], and strongly alkaline solutions such as NaOH or KOH, resulting in a rigid geopolymeric network
These materials are widely studied since they show interesting mechanical properties, thermal stability, freezethaw, chemical and fire resistance, long term durability and environmental advantages; for these reasons, their applications cover many fields
Summary
Geopolymers, known as “alkali-activated cements” or “alkali-activated aluminosilicates”, represent a new class of high performance inorganic materials characterized by a three dimensional, CaO-free, silico-aluminate chemical structure [1]. They can be produced by mixing reactive aluminosilicate materials such as metakaolin [2, 3], industrial [4] or natural waste products [5], and strongly alkaline solutions such as NaOH or KOH, resulting in a rigid geopolymeric network. At elevated temperatures, geopolymer concretes exhibit less potential to suffer from spalling in comparison with OPC concrete
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.
