西南石油大学学报（自然科学版）2017，Vol.39Issue(6)：63-68,6.DOI:10.11885/j.issn.1674-5086.2016.07.09.05
地层孔隙压力变化对井壁稳定性的影响研究
Study on the Effects of Changes in Pore Pressure on Wellbore Stability
摘要
Abstract
Long-term injection/projection operations cause large fluctuations in pore pressure,which in turn cause relatively large changes in rock strength and ground stress in the strata compared to the initial stage of mining.Furthermore,the complexity in the horizontal distribution of pore pressure induces and exacerbates wellbore instability and results in frequent occurrences of complex downhole situations.We carried out a combined theoretical and experimental study to understand the effects of pore pressure changes on the rock strength and stratum collapse pressure of sandstone strata.The results show that:(1) Rock strength is negatively correlated with pore pressure.As pore pressure increases,stratum rock strength and elastic modulus show a linear decrease.(2) Changes in pore pressure affect wellbore stability.Fractures,water injection,and polymer injection operations result in increased pore pressure around the well,which exacerbates wellbore instability.In addition,pressure-attenuated mining of oil and gas within a certain range decreases the stratum collapse pressure,which is beneficial for maintaining wellbore stability.关键词
井壁稳定/孔隙压力/岩石强度/坍塌压力Key words
wellbore stability/pore pressure/rock strength/collapse pressure分类
能源科技引用本文复制引用
李伟,梁利喜,刘向君,王涛..地层孔隙压力变化对井壁稳定性的影响研究[J].西南石油大学学报（自然科学版）,2017,39(6):63-68,6.基金项目
国家自然科学基金石油化工联合基金重点支持项目(U1262209) （U1262209）
国家自然科学基金(51274172) （51274172）
四川省应用基础研究计划(2014JY0092) （2014JY0092）
