Geogrid is a horizontal reinforcement material that is used in geosynthetic-reinforced pile-supported (GRPS) embankments in freeways with soft soil. Nevertheless, the long-term deformation mechanics of geogrid in the GRPS embankment under cyclic loading is not clear enough. This paper presents a laboratory model study of a GRPS embankment to study the long-term geogrid strain under cyclic loading. The effects of parameters such as number of load cycles, load frequency, geogrid layer numbers, and length of supporting piles on the long-term strain of geogrid were investigated. The results showed that geogrid strain increased with the number of load cycles, mainly developed in the first 10 000 load cycles and increased slowly in the later period. When the frequency was increased from 1 to 5 Hz, geogrid strain increased dramatically. When compared with the condition of a single geogrid layer, the upper layer of two geogrid layers caused a less geogrid strain. Compared with long piles and short piles GRPS embankments, a sufficient membrane effect of geogrid was found for long-short piles GRPS embankments. Finally, the 95% prediction interval proposed in this paper could be expressed using a logarithmic function, providing a theoretical foundation for future engineering applications.

中文翻译：

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循环荷载作用下 GRPS 路堤土工格栅长期应变研究

土工格栅是一种水平加固材料，用于软土高速公路中的土工合成材料加固桩支撑 (GRPS) 路堤。然而，循环荷载作用下 GRPS 路堤土工格栅的长期变形机制还不够明确。本文介绍了 GRPS 路堤的实验室模型研究，以研究循环荷载下的长期土工格栅应变。研究了荷载循环次数、荷载频率、土工格栅层数、支护桩长度等参数对土工格栅长期应变的影响。结果表明，土工格栅应变随着加载循环次数的增加而增加，主要发生在前10 000次加载循环，后期缓慢增加。当频率从 1 赫兹增加到 5 赫兹时，土工格栅应变急剧增加。与单层土工格栅的情况相比，两层土工格栅的上层引起的土工格栅应变较小。与长桩和短桩 GRPS 路堤相比，长短桩 GRPS 路堤具有充分的土工格栅膜效应。最后，本文提出的95%预测区间可以用对数函数表示，为以后的工程应用提供了理论基础。