毫米级宽度裂缝性漏失封堵实验研究

Experimental study on sealing millimeter-wide fracture leakage

论文采用不同抗弯强度的纤维和可变形橡胶粒子配合使用,在3块裂缝宽度均为1mm而裂缝面形态不同的人造钢岩样上开展了多组模拟堵漏实验。实验结果表明,以软硬纤维联合架桥、固相颗粒依次填充的堵漏方式能够有效封堵裂缝宽度为1mm的刚岩样,形成的封堵层承压能力达到了10MPa以上。对封堵层进行分析发现,封堵层中的硬纤维具有恢复弹性形变的趋势,而使封堵层能够适应动态变化裂缝的能力;封堵层中的软纤维与硬纤维形成网架结构,使封堵层具备较强的整体稳定性。最终,实验优选出适用于封堵毫米级宽度裂缝堵漏配方:基浆+2.5%QP-1+0.3%动物毛发+2.0%橡胶粒。

A series of experiments were conducted on three artificial iron cores with same width of 1mm and different fracture surfaceproperties with the help of fibers with different bending strengths and deformable rubber particles. Experimental results show that the pluggingmethod with fibers of different bending strengths bridging the fracture mouth and deformable rubber particles filling in the net structureformed by the fibers is effective to plug 1-millimeter fractures,and the pressure-bearing capacity of the plugging zone is higher than 10MPa.It is found that the fiber with high bending strength has the trend to recover which enables the plugging zone be suitable for re-plugging thedynamically changing fractures,and the net structure formed by the different fibers keeps the plugging zone stable in structure by analyzing thezone. Finally a formulation which is capable to plug millimeter-sized fractures is chosen with preference,that is,basic mud＋2.5%QP-1＋0.3%furs＋2.0%rubber particles.