Research On Prediction Of Cementcompressive Strength Of 28 Days Based On Early Resistivity

Strength is one of the most important indexes of cement quality. Especially the 28 days compressive strength of the cement. In the national standard provisions. The compressive strength of cement 28 days is the strength of the cement mortar after testing curing 28 days. The test of cement strength will take at least 28 days. Not only can not meet the requirements of production control of cement plant, it will seriously affect the construction process. Therefore, the fast and accurate prediction of the compressive strength of cement 28 days is the key to ensure the quality of cement plant. This paper mainly studies the resistivity of cement early. This paper mainly studies the resistivity of cement at early stage. Establish a prediction model of 28 days compressive strength of cement based on early resistivity.In this paper, we first use the method of electrochemical method to continuously monitor the early impedance behavior of the cement paste with different admixtures. And use the Zsimpwin software combined with the equivalent circuit of the internal structure characterization of cement resistance to different periods of cement paste values for fitting. So the resistivity of the cement paste is obtained by calculation. Further studies with different blended cement paste material whose resistivity changes with time curve.This paper discusses the feasibility and applicability of the method to study the hydration process of cement hydration heat method, resistivity method, thermal analysis etc. And the test results of different methods are analyzed. The research shows that the above method can study the hydration process of cement independently. But in some respects with the hydration process of cement is better than the heat of hydration method and thermal method. Study on hydration process of cement by resistivity method. According to the characteristics of the curve of electrical resistivity with time, the hydration process of cement can be divided into three stages. That is, the dissolution period, the induced formation stage and the induction period and the setting hardening stage.Through the study of cement paste electrical resistivity feature point changes with time curve and characteristic parameters, and the study of the early strength of the effective evaluation. The prediction model of compressive strength of 28 days cement finally established as follows:The research shows that the prediction of 28 days compressive strength of cement mortar with limestone is the most close to the measured value by using this model, Slag doped second. The results of fly ash are not the expect.In this paper,based on the electrical resistivity and compressive strength of cement 1d, the 28 days compressive strength is predicted. This provides a new method for the rapid detection of cement strength,and has important significance for rapid, accurate prediction of the 28 days compressive strength of cement.