煤层气压裂水泥环完整性研究

The study of cement mantle integrity problems in the process of CBM well fracturing

针对煤层气压裂施工过程中的水泥环力学完整性问题,采用弹塑性力学理论,建立了三种力学模型:包括"水泥环胶结良好"、"水泥环第二界面存在微环隙"及"水泥环内部存在微缺陷"。结合山西七元地区煤层气固井水泥石岩石力学参数,如弹性模量、泊松比、抗压强度、抗拉强度等,进行了工区地层条件下的水泥环完整性评价。

Aiming at the mechanical integrity problems of cement mantle in the process of CBM well fracturing, three mechanical models were established by using the elastic plastic mechanics theory, including "good cementation of cement mantle", "micro-annulus gap at the second interface of cement mantle" and "micro defects inside the cement mantle". Combined with the rock mechanics parameters of set cement in CBM wells in Qiyuan area of Shanxi province, such as elastic modulus, Poisson’s ratio, compressive strength and tensile strength, the integrity of cement mantle under the formation conditions of the work area was evaluated.