MTA方法固井二界面整体固化胶结实验

基于泥饼仿地成凝饼的科学构想,采用力学性能评价(如胶结强度)、微观结构分析(如X射线粉末衍射分析、热失重分析、环境扫描电子显微镜分析)和流体溶蚀实验等方法对MTA方法固井二界面整体固化胶结进行了实验研究。研究结果表明:随着养护时间的延长,用MTA方法得到的固井二界面胶结强度较目前提高了37.81%~1 606.31%;泥饼与水泥浆发生了局部的同步水化硬化反应,且生成了少量的团状水化硅酸钙(CSH(Ⅰ))凝胶和片沸石类凝胶,显示固井二界面整体固化胶结;流体溶蚀实验表明,采用目前方法,养护成型的样品浸泡28 d后,泥饼还原成了浑浊的稀钻井液,而用MTA方法得到的凝饼与水泥硬化体已胶结为一体,且凝饼未被溶蚀,表现为杯内流体仍清澈。这印证了两个事实:一是泥饼仿地成了凝饼,二是固井二界面已整体固化胶结。图6表1参16

Experiments on integrated solidification and cementation of the cement-formation interface based on Mud Cake to Agglomerated Cake (MTA) method

Based on the scientific conception of Mud Cake to Agglomerated Cake(MTA),the integrated solidification and cementation of cement-formation interface was studied by mechanical evaluation,microstructure analysis(XRD,TG and ESEM),and fluid dissolution test.The results of mechanical evaluation show that,compared with the existing method,the bond strength of cement-formation interface increased by 37.81 %-1 606.31 % with MTA method.The results of microstructure analysis show that the synchronous hydration and ha...