中文摘要：

在阶梯加载条件下对紫篷山砂岩进行了高温单轴压缩蠕变实验,利用参数变动法对砂岩稳态蠕变律常数进行了测定,同时,也对砂岩的稳态蠕变阶段进行了初步的研究。实验过程及结果表明,在实验的温压范围,即σ=8.6～77.8 MPa,T=20～500℃下,砂岩稳态蠕变率在10-10～10-9s-1之间,其随着温度和应力的增大而增大。温度越高,压力越大,砂岩的蠕变就越早进入稳态蠕变阶段。对砂岩稳态蠕变律常数的测定结果表明,在实验的温压范围内,应力指数n值表现出两段直线关系：应力σ在8.6～25.9 MPa之间时,应力指数n值在0.26～0.43之间;应力σ在25.9～77.8 MPa之间时,应力指数n值在0.61～0.82之间。应力指数n值有随着σ值的增大而增大的趋势。蠕变激活能QC值在0.05～3.796 k J/mol之间。当T在20～100℃之间时,T对QC的影响小。综合分析表明,在实验温压范围内,利用参数变动法对砂岩的蠕变激活能QC值进行测定有较大误差。在结构常数A的测定方面,ln A值均呈现负值,在-19.91～-14.59之间,这表明在实验的温压范围内,砂岩的微观结构、组分对稳态蠕变速率的影响是很小的。ln A值也存在着类似于应力指数n值的分段现象,表明了应力σ越大,砂岩的微观结构、组分对稳态蠕变速率的影响是越大。此外还对砂岩的弹性模量E进行了初步的研究。研究发现,弹性模量E随着应力的增大而增大,随着温度的增大而减小。

英文摘要：

On the basis of using parameter change law, the steady-state creep constants of sandstone （ sampled from ZiPeng Mountain） have been measured after uniaxial compression creep tests under step load, meanwhile, preliminary research on steady-state creep stage of sandstone was accomplished. The results show that steady-state creep rate of sandstone increases with the raise of temperature between 10-10 s-1 and 10-9 s-1, within the experi- mental range of temperature and pressure, σ= 8.6 - 77.8 MPa, T = 20 - 500 ℃. The higher the temperature and pressure, the earlier the threshold of steady-state creep stage appears. The result also indicates that, under the ex- perimental condition, stress exponent for steady-state creep exhibits two linear segments. Stress exponent（n） is be- tween 0. 26 -0.43 with the stress（o-） in 8.6 ～ 25.9 MPa and 0.61 -0. 82 with the stress in 25.9～ 77.8 MPa. The stress exponent shows increasing trend as σ increases. Creep activation energy（ Qc ） is between 0. 05 - 3.796 kJ/mol. Temperature（T） within 20 - 100 ～C, T have little influence on Qc- Analysis shows that it has more error using parameter change law to measure the creep activation energy under the experimental condition. The structure constant（lnA） has negative value between - 19.91 ～ - 14.59. The influence of micro-structure and component of sandstone on steady-state creep is weak but it rises as a increases. Moreover, a preliminary research on elastic modu- lus （E） of sandstone shows that E increases with the increase of tr and decreases with the increase of T.