Influence of Silica Fume Content on the Basic Mechanical Properties of Low-Heat Portland Cement Concrete

With the wide application of low-heat Portland cement in hydraulic projects, higher requirements are put forward for the mechanical properties of low-heat Portland cement concrete. In this study, the underwater steel ball method was used to quantify the influence of silica fume content (0, 3% and 5%) on the basic mechanical properties and other mechanical properties of low-heat Portland cement concrete. The results showed that the addition of silica fume could effectively improve the abrasion resistance of low-heat Portland cement concrete, which increased by 12.2% when the content was 3%, and increased by 14.6% when the content was 5%. Compared to concrete without adding silicon powder, when 3% silica fume was added, the compressive strength and split tensile strength of low-heat Portland concrete were respectively reduced by about 3.5%-6.0%, 3.8%-11.1%; axial tensile properties (axial tensile strength and ultimate tensile value) increased by about 7.0%; when 5% silica fume was added, the compressive strength, splitting tensile strength and axial tensile properties could be respectively increased by about 3.6%-7.0%, 2.8%-3.5%, 6.9%-14.8%. Therefore, a relatively ideal overall performance could be obtained when the content of silica fume was 5%.