Static mechanical properties and strengthening mechanism of nano carbon fiber modified concrete

As a widely used inorganic composite material, the brittleness of concrete is an important reason to limit the improvement of concrete performance. To improve the performance of concrete and study the modification effect of carbon nanofibers (CNFs) on concrete, this paper poured CNFs reinforced concrete specimens with different contents, and studied the static compressive strength, splitting tensile strength, and flexural strength of each group of specimens. The influence of CNFs on the micropore structure of concrete was analyzed by Mercury intrusion porosimetry (MIP). The results show that the addition of the appropriate amount of CNFs can enhance the static mechanical properties of concrete to varying degrees, and the optimal content of CNFs is 0.3%. CNFs can effectively reduce the content of macropores in concrete and optimize the pore structure of concrete. When the content is 0.3%, harmful holes and multi-harmful holes are reduced by 34.7% and 45.6% respectively.