硫酸盐腐蚀作用下膏体充填材料蠕变特性研究

为研究硫酸盐腐蚀后膏体充填材料的蠕变特性，采用饱和的Na2SO4溶液对充填体进行腐蚀试验，并对各个腐蚀时间不同的充填体采用TAW2000型岩石三轴试验机进行三轴蠕变试验。根据试验数据建立膏体充填材料的蠕变本构模型，将一个应变触发的非线性粘壶串联到Burgers模型上，建立满足充填体蠕变特性的改进Burgers模型，并推导其一维和三维蠕变本构方程。研究结果表明:在硫酸盐腐蚀作用下，充填体的蠕变变形在腐蚀6d时出现了一定的减少，但随着腐蚀时间的推移蠕变变形明显加大，在应力较大时出现了加速蠕变并导致试件破坏，硫酸盐腐蚀作用严重影响了充填效果；建立的改进的Burgers模型与试验数据基本吻合，能够反映腐蚀后充填体蠕变规律。

Study on creep property of paste filling materials under sulfate corrosion

In order to study the creep property of paste filling materials after sulfate corrosion, the corrosion test was conducted on filling paste by applying saturated Na2SO4 solution, and the triaxial creep test was conducted on filling paste with different corrosion time by applying the TAW2000 triaxial rock test machine. A creep constitutive model of paste filling materials was established according to the experimental data. A strain-triggering non-linear dashpot was connected to Burgers model to build an improved Burgers model fulfilling the creep property of the filling substance, and meanwhile, the one-dimensional and three-dimensional creep constitutive equations were derived. The results showed that under the influence of sulfate corrosion, the creep deformation of filling substance will suffer a decline in 6 d, but the creep deformation will be intensified obviously as the corrosion continues, and when the stress reaches a certain degree, the creep deformation will be accelerated and damage the test piece. Thus, sulfate corrosion has a significant impact on the filling effect. The improved Burgers model was basically consistent with the experimental data, and it can reflect the creep deformation rule of the filling substance after corrosion.