What are the disadvantages of adding algae powder to the cement paste?
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The disadvantages of adding algae powder to cement paste include potential reductions in compressive strength and hindrance to the hydration reactions of calcium silicates, leading to a permanent hindrance effect on hardening. Studies have shown that the compressive strength of cement paste can decrease significantly with higher concentrations of algae powder, especially beyond 5 wt %. Additionally, the presence of algae powder can lead to the formation of new hydration products with altered composition and micromorphology, deviating from the expected hardened cement compounds. Furthermore, the strength of concrete mixed with dried algae was found to be inversely proportional to the dry algal content, indicating that mixes with higher algae content may not perform as well as pure cement mixes .
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| Papers (4) | Insight |
|---|---|
Open access 01 Jan 2016 2 Citations | Adding algae powder to cement paste can reduce concrete strength, as shown in the study. Strength decreases with higher algae content, making it unsuitable for load-bearing applications. |
| Adding algae powder to cement paste can hinder hydration reactions, reducing compressive strength by over 80% after 91 days, due to encapsulation of calcium silicates by glucose-based carbohydrates formed during hydration. | |
| Adding algae powder to cement paste can lead to decreased strength properties beyond a certain threshold, as observed in the study where properties started to decrease with a 20% addition. | |
| Not addressed in the paper. |
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