关键词: 土工格栅, 加速蠕变, 低荷载水平, 时温叠加法, 长期蠕变特性

Abstract: Generally it takes a long period of time to complete conventional creep tests on geosynthetic materials. The test environment such as temperature and humidity should also be exactly controlled,which makes such tests very expensive and time consuming. Moreover, conventional creep test cannot predict the creep characteristics in design life. In view of this, the accelerated creep test method of short-term time-temperature superposition has been proposed.In this article, according to the principle of short-term time-temperature superposition,three groups of short-term creep tests of high-density polyethylene(HDPE) geogrids at 10%,20% and 30% load levels were conducted by three-axis electronic creep testing machine. Through the indoor creep tests,the long-term creep characteristics of the HDPE geogrids at each small load level were predicted. Results show that the long-term creep strain of the geogrids at 10%,20% and 30% load levels were low and the values at 10% load level maintained within 2%;the short-term time-temperature superposition principle takes relatively short time to predict the long-term creep strain and stiffness values of HDPE geogrids. This study could be used as reference for engineering application.

Key words: geogrid, accelerated creep, small load level, time-temperature superposition, long-term creep property