多元复合低密度水泥石早期固化强度研究  

Studies on Early Strength of a Low Density Multi-Element Composite Cement Slurry

作　　者：赵张平[1] 庄稼[1] 李焕明[1] 张梁[1] 

机构地区：[1]西南石油大学材料科学与工程学院,四川成都610500

出　　处：《石油钻探技术》2009年第5期72-76,共5页Petroleum Drilling Techniques

基　　金：山东胜油固井工程技术有限公司助研基金项目"超低密度水泥水泥浆的制备"部分研究内容

摘　　要：为了提高低密度水泥浆所形成水泥石的早期强度,以短切碳纤维作为水泥浆的增强剂,漂珠作为水泥浆的密度减轻剂,硅粉作为水泥浆的填充增强剂和稳定剂,并辅助一定量的添加剂,设计了一种碳纤维、漂珠、硅粉复合低密度水泥浆体系,采用正交试验方法分析了碳纤维、漂珠、硅粉加量对水泥石早期强度的影响。随漂珠加量的增大,水泥石的早期强度降低,但加量较小降低幅度较小,对水泥石的早期强度影响不大。随碳纤维加量的增大,水泥石的早期强度几乎呈线性增大。水泥石的早期强度随硅粉加量的增大呈现先增大后减小的趋势。碳纤维提高水泥石早期强度的机理是碳纤维跨架与水泥石的细微裂纹上,降低了微裂缝尖端的应力集中,从而约束裂纹的产生,防止裂缝扩展和连通。硅粉提高水泥石早期强度的机理是硅粉与水泥发生水化反应形成C—S—H凝胶填充在水泥石内部的空隙中,没有与水泥发生水化反应的硅粉直接填充于剩余空隙中,从而起到提高水泥石强度的作用。In order to increase the early strength of cured cement developed from low density cement slurry, a low density cement slurry comprising short carbon fiber and float beads and fine silica and other additives was designed. Effects of its components on early strength are analyzed separately using orthogonal tests. The results showed that the early strength decreases slightly with increased floating beads content, and increases almost linearly and then decrease with the increase of carbon fiber. The mechanism to enhance early strength with carbon fiber is that carbon fibers bridge across cement stone fractures so that the stress concentration on micro fracture top was reduced and thus prohibits fracture development and prevent fractures extending and communicating. The corresponding principle for fine silica is that the C-S-H gel developed from hydration between fine silica and cement particles is filled in internal pores among cement stone, and those fine silica without hydration is filled in remaining pores, therefore the cement strength is improved.

关 键 词：低密度水泥 抗压强度 实验室试验 碳纤维 漂珠 硅粉 

分 类 号：TE256.7[石油与天然气工程—油气井工程]