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Determination of Aggregate Surface Morphology at the Interfacial Transition Zone ITZ
Published on: December 16, 2019
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Eexperimental study of interface behaviour of geopolymer concrete
Karim Mohsen1, Ibrahim A Yousif2, Ehab F Sadek2
1Civil Engineering Department, Faculty of Engineering, Ain Shams University, Cairo, Egypt. karim.mohsen@eng.asu.edu.eg.
Scientific Reports
|September 24, 2025
Summary
Geopolymer concrete shows superior bond strength for structural strengthening. Manual roughening with acrylic agents yields the best results, outperforming traditional Portland cement concrete.
Area of Science:
- Civil Engineering
- Materials Science
Background:
- Flexural strengthening of reinforced concrete (RC) elements is crucial for enhancing structural capacity.
- Interface slip, often overlooked in monolithic design assumptions, significantly impacts damage levels.
- Bond strength and surface preparation are key determinants of interface slip.
Purpose of the Study:
- To experimentally assess the bond strength of geopolymer concrete (GPC) as a repair material.
- To evaluate the influence of surface preparation (manual roughening, sandblasting) and bonding agents (epoxy, cement-based) on GPC bond strength.
- To compare the performance of GPC with Portland cement concrete (PCC).
Main Methods:
- Experimental investigation of geopolymer concrete bond strength.
- Surface preparation techniques: manual roughening (chisel/hammer) and sandblasting.
- Bonding agents: epoxy-based and cement-based.
- Bond strength evaluation: slant shear and pull-off tests.
Main Results:
- Geopolymer concrete with 100% slag exhibited the highest bond strength (27.5 MPa slant shear, 1.8 MPa pull-off).
- GPC demonstrated a 25-35% improvement in bond strength over PCC under similar conditions.
- Manual roughening with an acrylic bonding agent yielded 40-50% higher bond strength than sandblasting with epoxy.
Conclusions:
- Geopolymer concrete offers excellent bond strength, making it a viable material for structural repair and strengthening.
- Optimized surface preparation and bonding agents significantly enhance the performance of GPC.
- The study provides valuable data for improving structural strengthening techniques and ensuring longevity.
Keywords:
Alkali activationBond behaviorConventional concrete (CC)Flexural behaviorFly ashGeopolymer concrete (GPC)Mechanical propertiesRetrofittingMore Related Videos
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