STUDY OF CREEP MECHANISM OF ARGILLACEOUS SOFT ROCKS
FAN Qiuyan1，YANG Keqing2，WANG Weiming3
(1. College of Resources and Metallurgy，Guangxi University，Nanning，Guangxi 530004，China；2. Geology and Mineral Engineering Investigation Institute of Nanning，Nanning，Guangxi 530007，China；3. College of Civil Engineering and Architecture，Shandong University of Science and Technology，Qingdao，Shandong 266510，China)
Abstract：Based on the analysis of existing research results of rock creep mechanism，the mudstone in Nanning Basin is taken as the mainly research object；and its creep property is deeply discussed by a series of tests under unconfined uniaxial compression and confined uniaxial compression. Especially，the creep changes of meso- and micro-structure are researched combining with scanning electron microscope(SEM) images of mudstone. It¢s indicated that the creep mechanism of the argillaceous soft rock is the result of the interaction between the damage effect and hardening effect. It is reasonable to explain and illustrate the mechanism of three creep phases by using the comprehensive curves，which include the creep curve，the damage effect curve and the hardening effect curve：at the first stage，hardening effect is much stronger than the damage effect and the creep mainly obeys the decay law of hardening effect at this stage；at the second stage，the damage effect is stronger than the hardening effect，and the creep mainly obeys the constant-rate law of the damage effect at this stage；at the third stage，the hardening effect disappears and the creep obeys the acceleration law of the damage effect. The creep mechanisms of the argillaceous soft rock and the metal materials are different in terms of magnitude of objects and the mechanism.
