摘要
分别对不同长度水镁石纤维油井水泥浆的流动性、API失水量、沉降稳定性进行了测试和分析;并讨论了纤维分散方式、加量范围、水泥石抗压强度、抗折强度、劈裂抗拉强度以及微观结构。结果表明,水镁石纤维能显著降低水泥浆体系流动性、使API失水量下降45%数50%,对水泥浆沉降稳定性的影响很小。水镁石纤维能显著提高水泥石的力学性能,水浴养护14 d后,3%纤维加量下的水泥石抗压强度提高16.2%,5%纤维加量下的水泥石抗折强度提高48.8%,8%纤维加量下的水泥石劈裂抗拉强度提高41.4%。通过机械剪切力和超声作用预分散处理后,水镁石纤维成细丝状均匀分布在水泥石中,能有效提高水泥石密实度和限制微裂纹发生与扩展。纤维的加入使得水泥石力学性能增益比显著增大,5%纤维加量水泥石的拉压比与空白试样相比提高27.5%,使得水泥石脆性得到较大改善。但高加量下水镁石纤维难分散、易团结,水镁石主要起填充作用,水泥石强度仍能得到一定的增加。
The liquidity,API filtration and sedimentary stability of fibers with different length were tested and analyzed in this paper. The dispersion and dosage of fibers in cement slurry and the compressive strength,flexible strength,tensile strength and the microstructure of cement paste were also discussed. The results showed that the cement slurry with brucite fibers could significantly decrease the liquidity and 45% —50% of API filtration,and barely impacted the sedimentary stability. And the mechanical properties of cement paste were significantly developed for 16.2%,48.8% and 41.4% by the dosage of 3% fibers for compressive strength,5% fibers for flexible strength and 8% fibers for tensile strength,after curing in water-bath for 14 days. When using the dispersion means of mechanical shearing and ultrasonic processing,the brucite fibers were uniformly distributed in cement paste as a single filiform fiber that could develop the compactness and confine the micro-fracture of cement paste. The mechanical property gain ratio of cement paste was increased noteworthy by fibers. The tensile compressive strength ratio of 5% fiber reinforced cement improved 27.5%. So the fibers could reduce the brittleness of cement paste as well. However,the brucite fibers with exorbitant dosage would be entanglement and disperse difficultly in cement paste. So the fibers only had filling effect and the strength of cement paste still got a certain amount of increase.
出处
《油田化学》
CAS
CSCD
北大核心
2015年第2期169-174,184,共7页
Oilfield Chemistry
关键词
水镁石纤维
油井水泥
分散方法
降脆
增韧
brucite fiber
oil well cement
dispersion method
brittleness reduction
toughen
