油砂力学及热学性质的试验研究  

Experimental research on mechanical and thermal properties of oil sand

作　　者：李存宝[1,2] 谢凌志[2,3] 陈森 窦升军 徐斌 

机构地区：[1]四川大学土木工程系,四川成都610065 [2]四川大学能源工程安全与灾害力学教育部重点试验室,四川成都610065 [3]四川大学新能源与低碳技术研究院,四川成都610065 [4]新疆油田公司采油工艺研究院技术研发中心,新疆克拉玛依834000 [5]BitCan地质科学与工程有限公司

出　　处：《岩土力学》2015年第8期2298-2306,共9页Rock and Soil Mechanics

基　　金：国家重点基础研究发展计划(No.2011CB201201);国际科技合作项目(No.2012DFA60760);四川省科技支撑计划(No.2012FZ0124)

摘　　要：通过对取自新疆克拉玛依风城油田重油储层的油砂进行室温和高温三轴固结排水压缩试验,研究了油砂基本力学和热学性质。研究结果表明:在常温试验条件下,油砂的偏应力-应变曲线可分为弹性阶段、塑性阶段和软化阶段,高温试验条件下则首先会出现压密阶段,不同围压下的体积应变变化规律显著不同;油砂的弹性模量和泊松比均与固结压力有较好的线性关系;高温对油砂的峰值强度、残余强度、泊松比和弹性模量影响很小;油砂的内摩擦角为34°,大小与粗粒土相近,凝聚力为0.47 MPa;油砂的热膨胀系数随围压的增大而增大,环向膨胀系数远大于轴向膨胀系数;围压?3=5 MPa时存在临界温度,使得油砂的变形在低于或高于临界温度时表现出不同的特点,当温度小于临界温度时,试件的环向变形、轴向变形、体积变形均随温度的升高线性膨胀;当温度大于临界温度时,试件的环向变形、轴向变形、体积变形均随温度的升高线性收缩。最后将风城油砂的性质与加拿大Athabasca和Cold Lake两处的油砂进行了对比,发现3个地区的油砂在强度、变形等方面有很多相似之处,这对风城重油资源的开采具有重要的指导意义。The consolidated drained triaxial compression tests on oil sand, which is from a heavy oil reservoir of Fengcheng oil field in Kelamayi, Xinjiang, are conducted at both room and high temperatures to study its mechanical and thermal properties. Experimental results show that the deviatoric stress-strain behaviour of oil sand at room temperature is divided into three stages： elastic, plastic and softening stages. At high temperature the compaction stage occurs before the elastic stage, however the variations of volumetric strain are significantly different at different confining pressures. Elastic modulus and Poisson＇s ratio of oil sand show a good linear relationship with the consolidation pressure. There is less effect of high temperature on the peak strength, residual strength, elastic modulus and Poisson＇s ratio. The values of internal friction angle and cohesion of oil sand are 34~ and 0.47 MPa respectively, which are close to those of coarse grained soils. The coefficient of thermal expansion increases with increasing confining pressure, and the circumferential expansion coefficient is sufficiently larger than the axial one. A critical temperature occurs at the confining pressure of 5 MPa. The deformation of oil sand presents varied characteristics as the temperature below or above the critical temperature. The axial, circumferential and volumetric deformations expand linearly with the increase of temperature when temperature is below the critical value, but the deformations reduce linearly when temperature is above it. Finally, comparing the properties of Fengcheng oil sand with Athabasca oil sand and Cold Lake oil sand, it is found that the strength and deformation characteristics ofoil sand are similar to great extent. Thus this study is particularly significant in the exploitation of heavy oil from the Fengcheng area.

关 键 词：风城油田 油砂 岩石力学 热学特性 试验研究 

分 类 号：TU458.3[建筑科学—岩土工程]