石油与天然气地质 ›› 2017, Vol. 38 ›› Issue (6): 1172-1179.doi: 10.11743/ogg20170618

• 油气开发 • 上一篇    下一篇

高温高压作用下致密砂岩三轴压缩试验

邓辉1,2, 张咪1, 邓通海1, 张茜1   

  1. 1. 成都理工大学 地质灾害防治与地质环境保护国家重点实验室, 四川 成都 610059;
    2. 成都理工大学 环境与土木工程学院, 四川 成都 610059
  • 收稿日期:2016-05-23 修回日期:2017-11-07 出版日期:2017-12-28 发布日期:2018-01-08
  • 作者简介:邓辉(1969-),男,博士、教授,岩土体稳定性。E-mail:330744407@qq.com。
  • 基金资助:
    国家自然科学基金项目(41272332)。

A triaxial compression test of tight quartz sandstone under high temperature and high confining pressure

Deng Hui1,2, Zhang Mi1, Deng Tonghai1, Zhang Qian1   

  1. 1. State Key Laboratory of Geohazard Prevention & Geoenvironment Protection, Chengdu University of Technology, Chengdu, Sichuan 610059, China;
    2. College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu, Sichuan 610059, China
  • Received:2016-05-23 Revised:2017-11-07 Online:2017-12-28 Published:2018-01-08

摘要: 为探究温度和围压对四川盆地新场气田须家河组二段致密石英砂岩力学性质和破坏方式的影响,利用MTS815电液伺服控制刚性试验机还原其地下深部高温高压的地质环境进行常规三轴压缩试验。结果表明,温度一定时,试样的三轴抗压强度和弹性模量平均值均随围压增大而增大;围压一定时,随试验温度升高,60℃之前,致密石英砂岩试样的粘聚力呈二次非线性减小,内摩擦角、三轴抗压强度及弹性模量呈非线性增加;60℃之后,各参数变化趋势则与之前相反。60℃是温度-围压共同作用条件下试样力学性质变化的温度节点。在0~100 MPa围压范围、15~150℃温度范围内,致密砂岩试样变形破坏类型取决于温度和围压,围压对岩石强度的影响程度大于温度。按试样破坏过程和破坏方式,可将应力-应变曲线大致分为5种类型,破坏方式包含拉张破坏、剪切破坏、剪胀破坏和拉张-剪切破坏。

关键词: 围压, 变形破坏类型, 常规三轴压缩试验, 致密石英砂岩, 新场气田, 四川盆地

Abstract: The impact of temperature and confining pressure upon mechanic characteristics and failure modes of the tight quartz sandstone in the second member of the Xuejiahe Formation(T3x2) in Xinchang gas field of Sichuan Basin,was studied through a conventional triaxial compression test by using a MTS 815 servo-controlled testing machine to simulate subsurface environment of high temperature and high confining pressure.The results show that,when the temperature remains constant,the average values of compressive strength and elastic modulus of quartz sandstone samples increase with growing confining pressure.And when under a constant confining pressure,the value changes in a two-stage way below and over the temperature of 60℃.Before the temperature reaches 60℃,the samples have a quadratic nonlinear decrease in terms of cohension and a nonlinear increase for their internal friction angle,triaxial compression strength,and elastic modulus.When the temperature is higher than 60℃,the above-mentioned parameters vary in a totally reverse direction.The temperature of 60℃ is then the critical point for the mechanical properties of the samples to reverse under joint control of temperature and confining pressure.Within the ranges of pressure from 0 to 100 MPa and temperature from 15 to 150℃,the deformation or failure modes of the samples depends on temperature and confining pressure,with the latter having stronger impact than that of the former.Based on deformation process and failure modes,we roughly categorize the stress-strain curves into five types,which in turn loosely correspond to failure modes of tensile,shear,shear dilatancy,and tensile-shear,respectively.

Key words: confining pressure, failure mode, conventional triaxial compression test, tight quartze sandstone, Xingchang gas field, Sichuan Basin

中图分类号: