砂泥岩组合体冲击动力学及破坏特征实验研究  

Experimental Research on Impact Dynamics and Damage Characteristics of Sand-Mudstone Assemblage

作　　者：汪翰林 李皋[1,2,3] 李红涛 王浩[1,2,3] WANG Hanlin;LI Gao;LI Hongtao;WANG Hao(National Key Laboratory of Oil&Gas Reservoir Geology and Exploration,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Underbalanced/Gas Drilling Laboratory,National Engineering Research Center of Oil&Gas Drilling and Completion Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China;School of Petroleum and Natural Gas Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China)

机构地区：[1]油气藏地质及开发工程全国重点实验室·西南石油大学,四川省成都市610500 [2]油气钻完井技术国家工程研究中心欠平衡/气体钻井实验室·西南石油大学 [3]西南石油大学石油工程学院

出　　处：《钻采工艺》2025年第2期41-49,共9页Drilling & Production Technology

基　　金：国家自然科学基金“深井超深井井筒多相瞬态流动模型与压力演变规律研究”(编号:51904264);四川省自然科学基金项目“超深层裂缝性气层钻井复杂工况井筒瞬态流动特性及井口回压控制压力反馈规律研究”(编号:2023NSFSC0929)。

摘　　要：为深入探究气体钻井作业时钻遇砂泥岩互层时发生井壁失稳的机理,文章采用霍普金森压杆实验系统,开展不同冲击载荷和静载条件下砂泥岩组合体冲击实验,分析砂泥岩组合体动力学特性、能量变化规律以及破坏特征。研究结果表明不同条件下砂泥岩组合体动态应力-应变曲线均存在线弹性、塑性屈服、峰后应力积蓄、破坏卸荷4个阶段,其动态抗压强度随轴压增加呈先增大后减小趋势,与冲击载荷和围压呈线性正相关关系;高冲击载荷下,砂泥岩组合体与压杆的波阻抗匹配效果更好,试样吸收的能量更多,三向静载增大会降低冲击载荷携带的能量进入岩石;砂泥岩组合体破坏主要表现在泥岩,砂岩更多承担能量蓄积与传递功能,冲击载荷对组合体破坏起正向激励作用,三向静载对组合体破坏起约束作用。研究结果有助于进一步认识气体钻井井壁失稳机理,为气体钻井安全作业提供一定的科学依据。To further investigate the mechanism of wellbore instability during gas drilling in sand-mud interlayers,a Hopkinson compression bar test system was employed to conduct impact tests on sand-mudstone assemblage under varying impact and static load conditions.The study aimed to analyze the dynamic characteristics,energy change patterns,and damage behaviors of the assemblages.The results indicate that:The dynamic stress-strain curves of the sandstone and mudstone assemblages under different conditions exhibit four stages:linear elasticity,plastic yielding,post-peak stress accumulation,and damage unloading.The dynamic compressive strength initially increases with the rise in axial pressure but then decreases;it shows a linear positive correlation with both impact load and confining pressure.Under high impact loads,the wave impedance matching between the sandstone and mudstone assemblages and the compression bar is improved,leading to higher energy absorption by the specimens.Additionally,increasing the three-way static load reduces the amount of energy transferred into the rock by the impact load.The damage in the sand-mud assemblages primarily occurs in the mudstone,while the sandstone plays a more significant role in energy accumulation and transfer.The impact load exerts a positive stimulating effect on assemblage damage,whereas the three-way static load exerts a restraining effect.These findings enhance the understanding of wellbore instability mechanisms during gas drilling and provide a scientific basis for ensuring safe drilling operations.

关 键 词：砂泥岩组合体 霍普金森压杆 动力学特性 能量 破坏 

分 类 号：TE21[石油与天然气工程—油气井工程]