一种层状盐岩相似材料的蠕变特性

Creep characteristic of a material similar with layered salt rock

为了在地质力学模型试验中更好地利用相似材料模拟层状盐岩的蠕变特性,以西气东输金坛盐穴储气库为工程背景,根据相似原理和原岩物理力学参数,通过大量的材料配比及力学试验,研制出符合该储气库层状盐岩力学特性的相似材料。该材料在蠕变试验中经历了初始蠕变、稳态蠕变及加速蠕变3个蠕变阶段,获得了相似材料在不同应力下的稳态蠕变率和长期强度,结果表明:其蠕变特性与盐岩原岩具有相似性,为地质力学模型试验中研究蠕变特性对盐穴稳定性的影响奠定了基础。

In order to make full use of similar materials to simulate the creep characteristics of layered salt rock in geomechanical model test, a great number of tests were carried out on material ratio and mechanics, and then a kind of similar material whose mechanical characteristic is in accordance with that of layered salt rock in Jintan salt-cavern gas storage of West-to-East Pipeline was developed in the engineering background of Jintan salt-cavern gas storage according to the similarity principle and the physical mechanical parameters of protolith. In the creep test, this similar material undergoes three creep stages（i.e., initial creep, steady-state creep and accelerating creep）. And by means of creep test, its steady-state creep rate and long term strength under different stresses were calculated. It is indicated that its creep characteristic is similar with that of protolith of salt rock. It provides the basis for studying the influences of creep characteristic on salt cavern stability in geo-mechanical model tests.