According to GB/T 18046—2000, the requirements for benchmark cement in the detection of total activity of mineral powder are: alkali content 0.5%-0.8%, 7-day strength 35-45 MPa. The 28-day strength is 50-60 MPa and the specific surface area is 300-400. 2.3%-2.8% of sulfur trioxide. If your benchmark cement does not reach the standard strength, we all know that mineral admixtures only react in the alkaline environment generated by cement hydration. The higher the strength, the finer the fineness of cement, the faster the reaction between dicalcium silicate and tricalcium silicate, the main strength sources in cement, and the more alkali released in a short time, which is beneficial to stimulate the activity of mineral powder. Therefore, the higher the strength of reference cement, the higher the total activity of the same mineral powder.