Investigation of mechanical behavior and physical characteristic of portland cement: Implications for destructive and non-destructive methods

摘要

Oilfield cements are a key element in well construction, during the operational phase of a well, and after its abandonment. Evaluating and understanding cement properties is crucial, since these properties are used in various engineering designs and calculations. In many scenarios, these properties are assumed constant with time, but an increasing number of studies have shown how properties change with time, temperature, and pressure. This work presents experiments run on API Class G cement mixed with and without additives and cured at 25 degrees C, 50 degrees C, and 75 degrees C, and constant pressure over a total of approximately two years. The influence of time, temperature, and additives on the performance of these cements is evaluated, and destructive and non-destructive testing methods are used to develop correlations to assess cement mechanical properties and to understand the development of porosity and its influence on cement performance. We applied NMR for the non-destructive evaluation of porosity, pore size distribution, cement water saturation, and curing of cement.