泥页岩水化应力模拟

Laboratory simulation of shales hydration pressure

基于传统岩石力学测定实验方法和泥页岩特性,分析泥页岩水化应力产生机理及其影响因素,建立泥页岩水化应力测试方法,并通过对原有实验仪器的改进,建立泥页岩水化应力定量测定模拟实验装置,实现泥页岩水化应力的定量测定.结果表明,该实验方法得当,实验仪器平行性好,最大误差为1%,完全可以满足泥页岩水化应力的定量测定,为泥页岩水化应力定量测定和深入研究泥页岩井壁稳定机理提供一种室内实验研究手段和方法;证明水化应力的存在,其最大值出现在泥页岩与水作用一定时间后,为井壁周期性坍塌提供解释依据.

The mechanism and impact factors of shales hydration pressure were analyzed,and the testing method was established based on the traditional rock mechanics measurement and shales' characters.A new simulation experimental instrument to quantitatively assay the shales hydration pressure was established by improvement on the original apparatus,and so the shales hydration pressure quantitatively assay became true.It is show that the method is properly and the instrument has a good parallelism,the maximum error is 1 percent,it can satisfy quantitatively assay the shales hydration pressure,and it provide a method & approach to quantitatively assay the shales hydration pressure and deeply study the shales borehole stability in laboratory.The experiment result approved that the shales hydration pressure is being,and the maximum pressure arise some time after shales/water action,it can be a foundation to interpret the periodically slough of wellbore.