油水井套变地层岩石力学参数反演分析

以套管变形测井资料为基础,利用APDL编制有限元优化模块反演套变围岩力学参数,即可确定套变地层缺失的力学参数,又克服目前套管变形分析多是基于弹性模型,不能进行塑性变形分析的问题。同时在岩石力学参数反演程序中引入莫尔―库伦破坏准则,确定岩层内摩擦角与黏聚力、最大水平主应力和最小水平主应力之间的关系,使反演解具有唯一性。该方法为套变围岩岩石力学参数的确定提供了新方法,并较传统反演方法更为简捷高效。

Analyses on the Inversion of Rock Mechanics Parameter in the Surrounding Formation of Oil-Water Wells with Casing Deformation

Based on the logging data of casing deformation,the optimal modules of finite element established by APDL program is applied to the inversion of rock mechanics parameters in the surrounding rock with casing deformation.This method can not only determine the lacked rock mechanics parameters of surrounding formation with casing deformation,but also can settle the present problem that analysis of casing deformation is based on the elastic model and thus unable to do plastic deformation analysis.Meanwhile,Mohr-Coulomb failure theory is applied to the inversion program of rock mechanics parameters in order to determine the relations between the angle of internal friction and its cohesion,maximum horizontal principal stress and minimum horizontal principal stress in the rock,and make the inversion solution uniqueness.Therefore,this method provides the new way for the determination of rock mechanics parameters of surrounding rock with casing deformation,and is more brief and efficient compared with traditional inversion method.