How does freeze thaw affect the strength of geopolymer?
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Freeze-thaw cycles significantly impact the strength of geopolymers. Studies have shown that the addition of certain materials like slag, polyoxymethylene (POM) fiber, and modified multi-walled carbon nanotubes (MWCNTs) can enhance the freeze-thaw resistance of geopolymers, thereby maintaining their strength. The presence of these additives helps in reducing the porosity of geopolymers, inhibiting cracking, and decreasing mass and strength loss ratios after freeze-thaw cycles. Additionally, the microstructure of geopolymers plays a crucial role in determining their response to cryogenic attack, with water transport and phase transitions influencing the strength variations observed during freeze-thaw cycles. Overall, optimizing the composition of geopolymers with suitable additives can effectively mitigate the detrimental effects of freeze-thaw cycles on their strength.
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01 Apr 2023 | Freeze-thaw cycles decrease geopolymer strength, with higher slag content (40.0% and 50.0%) showing improved resistance to strength loss under varying freezing temperatures (-1.0 ℃, -20.0 ℃, -40.0 ℃). |
| Freeze-thaw cycles decrease the compressive strength of polymer-improved sandy soil used in pavements. Increasing binder content compensates for the negative effect of particle roundness on strength. | |
| Freeze-thaw affects geopolymer strength differently based on water content and medium. Water-saturated geopolymer in water freeze-thaw medium showed the most significant strength decrease due to internal and external stresses. | |
12 Citations | Freeze-thaw cycles impact geopolymer strength. Mixed fibers like modified MWCNTs and PVA enhance resistance, allowing geopolymer to withstand more cycles by decreasing porosity and providing mechanical support. |
Related Questions
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