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The effects of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> on the physical, mechanical properties and durability of cement-based materials were investigated in this paper. The mechanical property, durability and SEM microscopic tests of test blocks with different Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> content were carried out. Results showed that Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> could improve the flexural strength, compressive strength and impermeability of cement-based materials. When the content of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> is 2.0%, the strengthening effect of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> on the cement-based materials was optimized, and the flexural strength of cement-based materials after 3 d, 7 d and 28 d increased by 12.6%, 18% and 32.4%, respectively, compared with the reference group. When the content of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> exceeded 2.0%, the flexural strength of cement-based materials begins to decline with the increase of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> content. Similarly, when the content of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> reached 2.0%, the impermeability of the cement-based materials was also optimized, and the permeability height of the base group could be increases by 41.4%. At the early stage of hydration, the exothermic rate of cement with 2.0% Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> content was higher than that of other contents. When the content of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> increased from 0 to 2.0%, the hydration exothermic rate increased gradually with the increase of Nano-<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>CaCO</mi><mn>3</mn></msub></semantics></math></inline-formula> content.