TY - JOUR
T1 - Compressive and splitting tensile impact properties of rubberised one-part alkali-activated concrete
AU - Elzeadani, M.
AU - Bompa, D. V.
AU - Elghazouli, A. Y.
N1 - Funding Information:
The first author appreciates the funding provided by the President's PhD Scholarship at Imperial College London for his research studies. The help provided by Mr. Andy Pullen, a research fellow in the Department of Civil and Environmental Engineering at Imperial College London, with regards to preparing the experimental setup for the dynamic tests is greatly acknowledged. The assistance provided by technical staff at the Structures Laboratory of Imperial College London, including that of Mr. Les Clark, Mr. Bob Hewitt, Mr. Paul Crudge, and Mr. Alfredo Olivo, regarding the preparation and testing of specimens is highly appreciated. The assistance provided by Dr. Marcus Yio, a research associate from the Centre of Infrastructure Materials at Imperial College London, vis-à-vis the material characterisation of aluminosilicate precursors is very much appreciated. Finally, the support of LKAB in providing the ground granulated blast furnace slag (GGBS) used in this study is greatly acknowledged.
Publisher Copyright:
© 2023
PY - 2023/7/15
Y1 - 2023/7/15
N2 - This paper presents an experimental assessment of the compressive and splitting tensile properties of rubberised one-part alkali-activated concrete under quasi-static and low-velocity impact loading. An optimised mix design, employing blast furnace slag and fly ash as precursors and anhydrous sodium metasilicate as a solid activator, is used as a reference. Rubber contents of up to 60% volumetric replacement of total natural aggregates are considered. Quasi-static tests are performed using servo-hydraulic machines, whilst the impact tests are performed in an instrumented drop-weight loading rig. Digital image correlation is used to get displacement measurements under both quasi-static and impact loading conditions. Three impact velocities of 5, 10, and 15 m/s are considered, giving rise to strain-rates in the range of 3–270 s−1. The quasi-static results show shape- and size-dependency and characteristically lower compressive and splitting tensile strengths with higher rubber content. The dynamic properties are notably influenced by the rubber content, with a higher ratio resulting in greater impact duration under compressive loading, reduced peak compressive strength, and reduced peak splitting tensile strength. The shape of the stress-strain response under compressive loading changes with rubber addition, showing two major peaks as opposed to a single peak for the non-rubberised specimens. The dynamic mechanical properties are also strain-rate dependent, exhibiting an increase with higher strain-rates. The rubberised specimens exhibit higher strain-rate sensitivity in splitting tension than compression, signified by higher dynamic increase factors for a given strain-rate and lower critical transition strain-rates. A higher rubber content in the mix also result in reduced critical transition strain-rates for the compressive strength, axial crushing strain, and splitting tensile strength. Based on the results of this study, analytical expressions are provided for predicting the dynamic increase factors for the compressive strength, axial crushing strain, elastic modulus, and splitting tensile strength.
AB - This paper presents an experimental assessment of the compressive and splitting tensile properties of rubberised one-part alkali-activated concrete under quasi-static and low-velocity impact loading. An optimised mix design, employing blast furnace slag and fly ash as precursors and anhydrous sodium metasilicate as a solid activator, is used as a reference. Rubber contents of up to 60% volumetric replacement of total natural aggregates are considered. Quasi-static tests are performed using servo-hydraulic machines, whilst the impact tests are performed in an instrumented drop-weight loading rig. Digital image correlation is used to get displacement measurements under both quasi-static and impact loading conditions. Three impact velocities of 5, 10, and 15 m/s are considered, giving rise to strain-rates in the range of 3–270 s−1. The quasi-static results show shape- and size-dependency and characteristically lower compressive and splitting tensile strengths with higher rubber content. The dynamic properties are notably influenced by the rubber content, with a higher ratio resulting in greater impact duration under compressive loading, reduced peak compressive strength, and reduced peak splitting tensile strength. The shape of the stress-strain response under compressive loading changes with rubber addition, showing two major peaks as opposed to a single peak for the non-rubberised specimens. The dynamic mechanical properties are also strain-rate dependent, exhibiting an increase with higher strain-rates. The rubberised specimens exhibit higher strain-rate sensitivity in splitting tension than compression, signified by higher dynamic increase factors for a given strain-rate and lower critical transition strain-rates. A higher rubber content in the mix also result in reduced critical transition strain-rates for the compressive strength, axial crushing strain, and splitting tensile strength. Based on the results of this study, analytical expressions are provided for predicting the dynamic increase factors for the compressive strength, axial crushing strain, elastic modulus, and splitting tensile strength.
KW - Dynamic increase factors
KW - Dynamic performance
KW - Impact loading
KW - One-part alkali-activated concrete
KW - Rubberised alkali-activated concrete
KW - Rubberised concrete
UR - http://www.scopus.com/inward/record.url?scp=85153105906&partnerID=8YFLogxK
U2 - 10.1016/j.jobe.2023.106596
DO - 10.1016/j.jobe.2023.106596
M3 - Journal article
AN - SCOPUS:85153105906
SN - 2352-7102
VL - 71
JO - Journal of Building Engineering
JF - Journal of Building Engineering
M1 - 106596
ER -